HomeMy WebLinkAbout06 09 2008_Historic Preservation_ Second Story AdditionsCommission Memorandum
Memorandum created on June 4, 2008 1
REPORT TO: Honorable Mayor & City Commission
FROM: Courtney Kramer, Assistant Planner, Brian Krueger, Associate Planner, Allyson
Bristor, Associate Planner
SUBJECT: Second Story Additions to one story houses; i.e. “Pop-Tops”
MEETING DATE: Monday, June 9, 2008
RECOMMENDATION: Bozeman City Commission members discuss and give guidance regarding the
Department of Planning’s approval or denial of second story additions to existing one story houses within the
City of Bozeman’s Neighborhood Conservation Overlay District and National Register of Historic Places
Historic Districts.
BACKGROUND: Over the last two months the Department of Planning and Community Development
received four applications to add livable space to a modest one story residence within the Neighborhood
Conservation Overlay District and informally discussed a potential project to that effect in the Bon Ton
National Register of Historic Places Historic District. Although the Administrative Design Review Staff
recognizes homeowner’s desire to invest in their property and add space to a traditionally smaller residence,
non of the proposals submitted comply with a number of sections and guidelines of the City of Bozeman’s
Unified Development Ordinance Chapter 18.28: The Neighborhood Conservation Overlay District (please
see addendum number one). These proposals also disregard the City of Bozeman’s Design Guidelines for Historic
Preservation and the Neighborhood Conservation Overlay District, which coach potential applicants on ways to
minimize the impact of an addition (please see addendum number two).
Both the Unified Development Ordinance and the Design Guidelines enable additions to historic properties.
The Design Guidelines recommend avoiding any negative impact of an addition by minimizing the loss of
historically significant features. Placing an addition at the rear of a building or set back at least ten feet from
the front reduces the visual impacts an addition has on a structure while respecting the mass and scale of an
original structure. The UDO requires staff to consider the addition’s impact on the height, proportion of
doors and windows, relationship of building masses and spaces, scale, directional expression, architectural
details, mechanical equipment and material and color choices.
Following the recommendations and guidance found in Chapter 18.28 of the UDO and the Design Guidelines,
ADR Staff believes approval of these proposals would be inappropriate. Staff believes that in most cases
there is space on the lot to create a modest first floor addition which has a positive impact on the surrounding
residences without inappropriately altering a historic structure.
The nationwide trend to add space to a one story structure through a new second story, often called “Popping
the Top,” is something akin to demolition, teardowns and “mansionization.” While structures which undergo
a “Pop-Top” generally retain their original footprint, these structures are vastly changed in height, massing,
scale, materials and orientation. The nature of this type of alteration impacts the streetscape and neighboring
properties, as well as prevents these properties from ever “contributing” to a National Register Historic
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Commission Memorandum
Memorandum created on June 4, 2008 2
District. Planning Staff believes the recent proposals signify the beginning of that trend in Bozeman and
respectfully asks the Commissioners guidance in regards to processing these applications.
ADR Staff is aware that each Certificate of Appropriateness application stands as uniquely individual. Given
the number of similar applications in a short period of time, as well as the national trend, Staff believed the
City Commission’s guidance prior to processing the existing applications is preferable to a denial and
appeals process.
UNRESOLVED ISSUES:
Neighborhood Conservation Overlay District:
· Does the Commission wish to generally allow second story additions to one story houses within the
Neighborhood Conservation Overlay?
· Does the Commission wish to only approve second story additions to one story houses within the
Neighborhood Conservation Overlay deemed “non-contributing” to a potential historic district?
· Does the Commission wish to approve or prohibit second story additions to one story houses within
the Neighborhood Conservation Overlay deemed “contributing” to a potential historic district?
National Register of Historic Places Historic Districts:
· Does the Commission wish to only approve second story additions to one story houses within an
existing National Register of Historic Places Historic District deemed “non-contributing” to a
potential historic district?
· Does the Commission wish to approve or prohibit second story additions to one story houses within
an existing National Register of Historic Places Historic District deemed “contributing” to a potential
historic district?
The size and shape of approvable second story additions:
· Does the Commission wish to only approve second story additions to one story houses which abide
by the City of Bozeman’s Design Guidelines for Historic Preservation and the Neighborhood Conservation Overlay
District, to place an addition at the rear of a building or set it back at least ten feet from the front to
minimize the visual impacts.
FISCAL EFFECTS:
ALTERNATIVES: As suggested by the City Commission.
CONTACT: Please email Courtney Kramer at ckramer@bozeman.net if you have any questions prior to the
public meeting.
APPROVED BY: Andrew Epple, Planning Director
Chris Kukulski, City Manager
Addendum:
Addendum One: Bozeman Municipal Code Unified Development Ordinance Section 18.28 “The
Neighborhood conservation Overlay District”
Addendum Two: Selected chapters of the City of Bozeman’s Design Guidelines for Historic Preservation and the
Neighborhood Conservation Overlay District
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CHAPTER 18.28
NEIGHBORHOOD CONSERVATION OVERLAY DISTRICT
18.28.010 INTENT AND PURPOSE
A. All new construction, alterations to existing structures, movement of structures into or
out of the neighborhood conservation overlay district, hereinafter referred to as the
conservation district, or demolition of structures by any means or process will be
subject to design review. The recommendations of the Design Review Board or
Administrative Design Review staff shall be given careful consideration in the final
action of the Planning Director or City Commission.
B. This chapter defines and sets forth standards which apply to the conservation district.
C. The intent and purpose of the conservation district designation is to stimulate the
restoration and rehabilitation of structures, and all other elements contributing to the
character and fabric of established residential neighborhoods and commercial or
industrial areas. New construction will be invited and encouraged provided primary
emphasis is given to the preservation of existing buildings and further provided the
design of such new space enhances and contributes to the aesthetic character and
function of the property and the surrounding neighborhood or area. Contemporary
design will be encouraged, provided it is in keeping with the above-stated criteria, as
an acknowledged fact of the continuing developmental pattern of a dynamic,
changing community. The neighboring community shall be provided notice and
opportunity to comment upon the proposed property improvements in accordance
with Chapter 18.76, BMC. In addition, aggrieved persons shall have the right to
appeal any design review decision made under the provisions of this chapter, in
accordance with Chapter 18.66, BMC.
D. In view of the fact that most of the area included within the boundaries of the
conservation district was developed and built out prior to the adoption of zoning
and contemporary subdivision regulations, the construction, development pattern
and range of uses is highly diverse and frequently not in compliance with
conventional regulatory requirements. This chapter recognizes that this diversity is a
major contributing element of the historic character of these neighborhoods or areas.
The provisions of this chapter shall be applied in a manner that will encourage the
protection and enhancement of the many diverse features for future generations.
E. The conservation district boundary is largely coterminous with the area surveyed in the
effort that led to the listing of nine historic districts and 40 additional landmark
structures in the National Register of Historic Places, and includes the nine
designated historic districts and 40 individual landmarks. This chapter sets forth the
means of protecting and enhancing the conservation district.
F. It is further the purpose of the conservation district designation to protect and enhance
neighborhoods or areas of significant land planning or architectural character,
historic landmarks or other built or natural features for the educational, cultural,
economic benefit or enjoyment of Bozeman citizens. It will be the policy and
responsibility of the administrative entities of this chapter to:
1. Protect, preserve, enhance and regulate structures, archaeological or cultural sites,
and areas that:
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a. Are reminders of past eras, events or persons important in local, state or
national history;
b. Provide significant examples of land planning or architectural styles, or are
landmarks in the history of land planning and architecture;
c. Are unique or irreplaceable assets to the City and its neighborhoods;
d. Provide examples of physical surroundings in which past generations lived;
or
e. Represent and express the unique characteristics of small agricultural-
based, western city developmental patterns;
2. Enhance property values through the stabilization of neighborhoods and areas of
the City, increase economic and financial benefits to the City and its
inhabitants, and promote tourist trade and interests;
3. Develop and maintain the appropriate environment for buildings, structures, sites
and areas, that reflect varied planning and architectural styles and
distinguished phases of Bozeman’s history and prehistory;
4. Stimulate an enhancement of human life by developing educational and cultural
dimensions, which foster the knowledge of Bozeman’s heritage, and cultivate
civic pride in the accomplishments of the past;
5. Seek to maintain and enhance the many private and public elements that are
unique to the fabric, theme and character of each neighborhood and area,
including but not limited to: lighting, pathways, street trees, natural areas and
other features that may, from time to time, be identified by the citizens and
property owners of neighborhoods, areas and subsections thereof; and
6. Provide the neighboring community with notice and opportunity to comment
upon the proposed property improvements in accordance with Chapter
18.76, BMC, with the exception of certain sketch plan applications with
potentially little neighborhood impact, and to further provide aggrieved
persons with the right to appeal review decisions made under the provisions
of this chapter, in accordance with Chapter 18.66, BMC.
18.28.050 STANDARDS FOR CERTIFICATES OF APPROPRIATENESS
A. All work performed in completion of an approved certificate of appropriateness shall be
in conformance with the most recent edition of the Secretary of Interior’s Standards
for the Treatment of Historic Properties with Guidelines for Preserving,
Rehabilitating, Restoring and Reconstructing Historic Buildings (Published 1995),
published by U.S. Department of the Interior, National Park Service, Cultural
Resource Stewardship and Partnerships, Heritage Preservation Services, Washington,
D.C. (available for review at the Planning Department).
B. Architectural appearance design guidelines used to consider the appropriateness and
compatibility of proposed alterations with original design features of subject
structures, or properties and with neighboring structures and properties, shall focus
upon the following:
l. Height;
2. Proportions of doors and windows;
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3. Relationship of building masses and spaces;
4. Roof shape;
5. Scale;
6. Directional expression, with regard to the dominant horizontal or vertical
expression of surrounding structures;
7. Architectural details;
8. Concealment of nonperiod appurtenances, such as mechanical equipment; and
9. Materials and color schemes (any requirements or conditions imposed regarding
color schemes shall be limited to the prevention of nuisances upon abutting
properties and prevention of degradation of features on the property in
question. Color schemes may be considered as primary design elements if a
deviation from the underlying zoning is requested).
586
Design Guidelines for Historic Preservation and the Neighborhood Conservation
Overlay District
Introduction:
Chapter 1: Rehabilitation Guidelines for Historic Properties
A. Character-Defining Features (p. 21)
C. Individual Building Features (p. 26)
E. Rehabilitation of Historic Residential Properties
Additions to Residential Properties (p. 39)
Chapter 2: Design Guidelines for All Properties
B. Street Patterns (p. 45)
D. Streetscape (p. 47)
F. Building Form (p. 48)
G. Solid-to-Void Ratio (p. 49)
H. Materials (p. 50)
I. Architectural Character (p. 51)
Chapter 3: Guidelines for Residential Character Areas
A. Hierarchy of Public and Private Space (p. 57)
B. Building Mass and Scale (p. 58)
C. Roof Form (p. 59)
D. Secondary Structures (p. 59)
587
Introduction 1
INTRODUCTION
Cooper Park Historic District
588
2 Design Guidelines
In this Chapter:
Part I: OverviewA. Background of Bozeman Design Guidelines ProjectB. Preservation Goals for BozemanC. Basic Preservation TheoryD. Preservation PrinciplesE. Choosing an Approach GlossaryF. Planning a Preservation Project
Part II: Design Review systemA. Bozeman Neighborhood Conservation Overlay District B. Background of Design GuidelinesC. Determining Compliance with the GuidelinesD. Which Guidelines Apply?E. Policies Underlying the Design GuidelinesF. Components of Design GuidelinesG. Applying for a Certifi cate of Appropriateness (COA)
This chapter introduces the design guidelines and describes how and when they should be used in the Bozeman community.
589
Introduction 3
INTRODUCTION
Part I: OverviewHistoric preservation and neighborhood conservation are well-established parts of city planning in Bozeman. Over the past decades, the community has initiated preservation initiatives to protect the many historic districts and older traditional neighborhoods that remain as reminders of the City’s heritage. While change continues to occur in response to varying community goals and economic conditions, preserving Bozeman’s heritage remains a primary goal of the community. These design guidelines are written for use by City Staff, property owners, residents and others to foster the preservation of historic residential and commercial districts and to maintain the traditional character of the broader Neighborhood Conservation Overlay District.
A. Background of the Bozeman Design Guidelines Project
The City of Bozeman resolved to create an interactive process for the Neighbor-hood Conservation Overlay District Design Guidelines project, through which the residents of Bozeman, the Historic Preservation Advisory Board (HPAB) and Design Review Board (DRB) expressed their concerns and expectations for the fi nal product. The result has been a cooperative system of dialogue and values-clarifi cation from which the City determined relevant concerns and goals for the District. This was accomplished through several public workshops. At these sessions, participants discussed positive attributes of the City’s historic neighborhoods and identifi ed design issues that cause concern about future development. By completing exercises and discussions, the Bozeman residents took an active role in shaping the guidelines for the District.
B. Preservation Goals for Bozeman
A primary design goal for Bozeman is to preserve the integrity of its individual historic structures and the character of its streetscapes in the Neighborhood Conservation Overlay District. To maintain the character of a historic building, design elements such as form, mass and materials should be considered in any alteration. The relationship each building has with other neighborhood design elements is also important, as well as the hierarchy of site elements, such as street trees, front yards, walkways and accessory structures.
The overall design goal for
Bozeman is to preserve the
integrity of its individual
historic structures and the
character of its streetscapes
that are unique or irreplaceable
assets to the City and its
neighborhoods.
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4 Design Guidelines
C. Basic Preservation Theory
The Concept of Historic Signifi cance
What makes a property historically signifi cant? In general, properties must be at least 50 years old before they can be evaluated for potential historic signifi cance, although exceptions do exist when a more recent property clearly has historical value. A property may be signifi cant for one or more of the following reasons:• Association with events that contributed to the broad patterns of history, the lives of signifi cant people or the understanding of a community’s prehistory or history.• Construction and design associated with distinctive characteristics of a building type, period or construction method.• An example of an architect or master craftsman or an expression of particularly high artistic values.• Integrity of location, design, setting, materials, workmanship, feeling and association that form a district.• An established and familiar natural setting or visual feature of the community.
Period of Signifi canceIn most cases, a property is signifi cant because it represents or is associated with a particular period in its history. Frequently, this begins with the construction and continues through the peak of its early occupation. Building fabric and features that date from the period of signifi cance typically contribute to the defi ning character of the structure.
Historic districts also have a period of signifi cance. Specifi cally to each district, there is a more concise “period of signifi cance” noted in the National Register nominations. Throughout each of these periods the historic districts have been witness to a countless number of buildings and additions which have become an integral part of the neighborhood. Conversely, several structures have been built or alterations have been made after this period which are generally considered non-contributing and may be considered for removal or replacement. In general keep this in mind:
591
Introduction 5
Concept of IntegrityA property also must have integrity, in that a suffi cient percentage of the struc-ture must date from the period of signifi cance. The majority of the building’s structural system and materials should date from the period of signifi cance and its character-defi ning features also should remain intact. These may include ar-chitectural details such as dormers, porches, ornamental brackets, moldings and materials, as well as the overall mass and form of the building. These elements allow a building to be recognized as a product of its own time.
AlterationsMany historic structures have experienced alterations over time, as design tastes changed or need for additional space occurred. In some cases, an owner would add a wing for a new bedroom, or to expand the kitchen. Early alterations typically were subordinate in scale and character to the main building and were often executed using materials that were similar to those in use historically.
Some early alterations may have taken on historic signifi cance of their own. One constructed in a manner that is compatible with the original building and that is associated with the period of signifi cance may merit preservation in its own right.
In contrast, more recent alterations usually have no historic signifi cance. Some later additions detract from the character of the building and may obscure signifi cant features, particularly enclosed porches. Removing such additions or alterations may be considered in a rehabilitation project.
This tradition of alterations is anticipated to continue. It is important, however, that new alterations be designed in such a manner that they preserve the historic character of the primary structure.
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6 Design Guidelines
D. Preservation Principles
The following preservation principles should be applied to all historic properties:
• Respect the historic design character of the building. Don’t try to change its style or make it look older than its actual age. Confusing the character by mixing elements of different styles can weaken the appearance and historic quality of the structure.
• Seek uses that are compatible with the historic character of the building. Building uses that are closely related to the original use are preferred. Every reasonable effort should be made to provide a compatible use for the building that will require minimal alteration to the building and its site.
Property owners should consider the impacts that some changes in use would have upon their historic properties, since this may affect design considerations that are reviewed by the Department of Planning. Check the Unifi ed Development Ordinance (UDO) to determine which uses are allowed.
Change in uses requiring the least alteration to signifi cant elements are preferred. In some instances, however, a radical change in use may be necessary to keep the building in active service. In order to adapt a building to the proposed new use, the alterations may be too extreme and the proposed loss of historic building fabric would require a reassessment of a more appropriate use. Experience has shown that in most cases designs can be developed that respect the historic integrity of the building while also accommodating new functions. Note that more radical changes in use can make projects more expensive or result in the loss of signifi cant features. Carefully evaluate the cost of alteration, as adaptation for a radical change may prove too costly or destroy too many signifi cant features.
• Protect and maintain signifi cant features and stylistic elements. Distinctive stylistic features or examples of skilled craftsmanship should be treated with sensitivity. The best preservation procedure is to maintain historic features from the outset to prevent intervention. Protection includes the maintenance of historic material through treatments such as rust removal, caulking, limited paint removal and reapplication of paint.
• Preserve any existing original site features or original building materials and features. Preserve original site features such as a rock retaining walls. Avoid removing or altering original materials and features. Preserve original doors, windows, porches and other architectural features.
593
Introduction 7
• Repair deteriorated historic features, and replace only those elements that cannot be repaired. Upgrade existing material, using recognized preservation methods whenever possible. If disassembly is necessary for repair or restoration, use methods that minimize damage to original materials and the replacement of original confi guration. E. Choosing an Approach Glossary
Preservation projects may include a range of activities, such as maintenance of existing historic elements, repairs of deteriorated materials, the replacement of missing features and construction of new additions. When planning a preservation approach, consider the defi nitions of the following terms:
• Preservation. The act or process of applying measures to sustain the existing form, integrity and material of a building. Some work focuses on keeping a property in good working condition by repairing features as soon as deterioration becomes apparent, using procedures that retain the original character and fi nish of the features. Property owners are strongly encouraged to maintain properties in good condition.• Rehabilitation. The process of returning a property to a state that makes a contemporary use possible while still preserving those portions or fea-tures of the property which are signifi cant to its historical, architectural and cultural values. Rehabilitation may include a change in use of the building or additions. • Renovation. The process of improving by repair, to revive. In renova-tion, the usefulness and appearance of the building is enhanced. The basic character and signifi cant details of a building are respected and preserved, but some sympathetic alterations may also occur. • Restoration. The process of reproducing the appearance of a building exactly as it looked at a particular moment in time. This may include the removal of later work or the replacement of missing historic features. • Remodeling. The process of changing the historic design of a building. The appearance is altered by removing original details and by adding new features that are out of character with the original. Remodeling of an historic structure is inappropriate due to the loss of original fabric.• Reconstruction. The process of rebuilding a structure that no longer exists exactly as it appeared historically.
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8 Design Guidelines
F. Planning a Preservation Project
The fi rst step in planning a preservation project is to identify any character-defi ning features and materials of the structure. Retaining such details will greatly enhance the overall quality of the project. If they are in good condition, then selecting an appropriate treatment will provide for proper preservation. In making the selection, follow this sequence:
• Preserve:If a feature is intact and in good condition, maintain it as such.• Repair:If the feature is deteriorated or damaged, repair it to its original condition.• Replace:If it is not feasible to repair the feature, then replace it with one that is the same or similar in character (e.g., materials, detail, fi nish) to the original one. Replace only that portion which is beyond repair.• Reconstruct:If the feature is missing entirely, reconstruct it from appropriate (photographic) evidence. (This treatment is only appropriate for small portions of a project, not the majority of the work.)• If a new feature or addition is necessary, design it in such a way as to minimize the impact on original features.
In essence, the least level of intervention is preferred. By following this tenet, the highest degree of integrity will be maintained for the property.
595
Introduction 9
Part II: Design Review System
A. Bozeman Neighborhood Conservation Overlay District
The Neighborhood Conservation Overlay District is an area that was created by the City of Bozeman to recognize the historic core of the Bozeman community. It encompasses Bozeman’s nine National Register of Historic Places historic districts, as well as the many individual National Register listings. Please see Chapter 5 for a detailed description of each historic district.
All proposed alterations (including demolition) to structures and sites within the area are subject to design review by the City of Bozeman Department of Planning and are subject to standards set forth in the City of Bozeman Unifi ed Development Ordinance (UDO), in addition to these particular design guidelines.
As stated in the UDO, “the intent and purpose of the conservation district designation is to stimulate the restoration and rehabilitation of structures, and all other elements contributing to the character and fabric of established residential neighborhoods and commercial or industrial areas.”
Further, the ordinance states that while new construction is invited and encouraged, “primary emphasis is given to the preservation of existing buildings, provided the design of such new places enhances and contributes to the aesthetic character and function of the property and the surrounding neighborhood or area.”
The essential idea behind the Neighborhood Conservation Overlay District concept is to protect Bozeman against alteration and demolition that might damage the unique fabric created by the hundreds of important buildings and sites that make up the historic core of Bozeman.
How does the City of Bozeman administer proposed alterations to structures and sites located in the Neighborhood Conservation Overlay District?Exterior alterations, such as a new fence or a new addition, that occur within the Neighborhood Conservation Overlay District are largely administered through the City Historic Preservation Offi ce, a division of the Bozeman Department of Planning and Community Development. The Historic Preservation Offi ce and Administrative Design Review Staff will use this document, in addition to the standards set forth in the UDO, as a guide for determining the historical appropriateness of a proposed building alteration.
Generally, interior alterations, landscaping, painting, and minor repair with like materials are not under the jurisdiction of the City of Bozeman. However, it is important to note that the replacement or modifi cation of features with a new type or material does require approval from the City. If the previous feature was constructed before the current UDO was enacted, the City may view the replacement construction as an opportunity to bring the element into code compliance.
Alteration: Any act or process,
except repair and light con-
struction that changes one
or more of the architectural
features of a structure or
site, including, but not limited
to, the erection, construction,
reconstruction, relocation of,
or addition to a structure.
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10 Design Guidelines
My home is located within the Neighborhood Conservation Overlay District. What procedures must I follow to alter my property?If a resident within the Neighborhood Conservation Overlay District intends to alter the exterior of their home, they must apply for a Certifi cate of Appropriate-ness, or COA, through the Department of Planning. The applicant is required to submit application material regarding the project, including a scaled site plan, elevation drawings, and photographs of the project location. Once an application is deemed complete, the design review process begins. A COA, as the name implies, is certifi cation that the design of a project is appropriate for the historic neighborhood or area in which it is located. COA approval is required for any alteration (including sign or fence construction), demolition, or new construction within the Neighborhood Conservation Overlay District. Interior modifi cations to property within the District are not subject to COA review, unless the property is a National Register contributing structure that is frequented by the general public.
What if I want to demolish, or move, a building on my property?The demolition and movement of structures within the Neighborhood Conservation Overlay District are considered an alteration and therefore are also subject to review by City Staff. Application for the demolition or removal of structures within the Neighborhood Conservation Overlay District will not be accepted without a comprehensive plan for the subsequent development of the property. This plan must be approved before a demolition or moving permit is issued. Generally, if the building has been determined to be historically signifi cant, fi nal authority for the demolition or movement shall rest with the City Commission.
Where can I locate further information?The City of Bozeman provides information related to zoning and community development, including the Bozeman 2020 Community Plan. Find out more about local planning at: http://www.bozeman.net/planning.html
There are many online resources that can provide information related to Bozeman’s Neighborhood Conservation Overlay District. Additional design standards such as “The Secretary of the Interior’s Standards for Rehabilitation” can be located online at: http://www2cr.nps.gov/tps/standguide/index.htm
The Montana State Historic Preservation Offi ce (SHPO) is another excellent source for preservation information:http://www.his.state.mt.us/departments/shpo/index.html
If the property is a “contributing” element within one of Bozeman’s National Register historic districts, and it is income-producing, it may be eligible for preservation-related federal tax credits. More information can be located at: http://www2.cr.nps.gov/tps/tax/index.htm
Examples of Alteration:
• building addition
• new window(s)
• change in roof materials
• fence
• change in exterior siding
materials
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Introduction 11
B. Background of Design Guidelines
What are Design Guidelines?The guidelines convey general policies about the design of alterations to exist-ing structures, additions, new construction and site work. However, they do not dictate solutions. Instead, they defi ne a range of appropriate responses to a variety of specifi c design issues.
Why have Design Guidelines?The purpose of the guidelines and the review process through which they are administered is to promote preservation of the historic, cultural and architectural heritage of Bozeman. These resources are fragile and are vulnerable to inappropriate alteration and demolition. Recognizing this concern, Bozeman established these guidelines.
One purpose for these guidelines is to inform the community about the design policies the city holds for the overlay district. They indicate an approach to design that will help provide information that property owners may use to make decisions about their buildings and to maintain their historic character. The guidelines also provide Bozeman a basis for making informed, consistent decisions about design.
The design guidelines provide a basis for making consistent decisions about the treatment of historic resources. They also serve as educational and planning tools for property owners and their design professionals who seek to make improvements that may affect historic resources.
While the design guidelines are written for use by the layperson to plan improvements, property owners are strongly encouraged to enlist the assistance of qualifi ed design and planning professionals, including architects and preservation consultants.
Known for its ongoing preservation efforts, the Bozeman Neighborhood Conservation Overlay District is foreseeing continued investment in the area, including renovation, additions to existing buildings and infi ll construction. Therefore, a wide range of construction projects are anticipated and the pressure on the historic district's integrity is increased, as is the need for guidelines.
C. Determining Compliance with the Guidelines
The Department of Planning and Community Development will administer the guidelines. In doing so, they will consider how each proposed project meets the guidelines and how the proposed work would therefore help to accomplish the design goals set forth in this document and in the Unifi ed Development Ordinance (UDO).
A project may fall into a special review category because of its size or design complexity. In this case the Historic Preservation Advisory Board (HPAB) and/or the Design Review Board (DRB) may be consulted to advise City Staff on the appropriateness of the project design.
It is important to note that the
City has the right to update,
change and revise previously
assigned project types. For
example, the Montana Historical &
Architectural Inventory files
may assign a property a non-
contributing status; after
reassessing the building, it
may in fact be reassigned as
a contributing property to the
district. Any changes to the
building would then need to
follow the guidelines for that
project type.
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12 Design Guidelines
D. Which guidelines apply?
The guidelines apply to all work subject to design review in the Neighborhood Conservation Overlay District, as well as to individual National Register properties that may be located elsewhere in the City. However, different chapters will apply, depending upon the type of property. Those that have historic signifi cance will have guidelines for preservation to be considered, along with other general standards, while more general guidelines for compatibility apply to a new building. In addition, some guidelines vary by building type. Those for commercial buildings, for example, are different from those for residences. The following is a general overview of different project types and their related guidelines:
1. Contributing PropertyA building that is identifi ed as having signifi cance and contributing to the character of a designated historic district is considered “contributing.” These are identifi ed on the Montana Historical & Architectural Inventory fi les, but in some cases, signifi cance may be determined at the time that an application for approval is submitted. For these properties, preservation of the key character-defi ning features is the objective. Focus is on the rehabilitation guideline, design guidelines for all properties, and other more context-sensitive district guidelines.
2. Non-Contributing PropertyA building found within a designated historic district, but which does not contribute to the signifi cance of the district, is considered “non-contributing.” This may be a newer building that has not taken on signifi cance, or it may be an older one that has been so substantially altered that it lacks integrity as a historic resource. For these properties, the guidelines for all properties apply, which address how buildings may fi t within a neighborhood. In addition, guidelines for the building type apply, as well as those in the special chapter for the historic district in which the property lies. Rehabilitation guidelines do not apply. The objective is to assure that if the property is altered, the result would be compatible with the historic context. Preservation of features on the building itself is not a priority. It is important to note that with appropriate rehabilitation, a building may move to a “contributing” status. The Historic Preservation Offi ce recommends all property owners consider this approach in alteration projects.
3. National Register Individual ListingA property that, on its own, has suffi cient signifi cance to be considered a historic resource may be designated individually on the National Register. For these, preservation is the objective, and the guidelines for rehabilitation are to be applied. The design guidelines for all properties would also apply.
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Introduction 13
Note: A blank box indicates that the chapter does not apply.
* Chapter 2, Chapter 3 and Chapter 4 guidelines will be applied more rigorously on projects in these districts.
HOW THE GUIDELINES APPLY
1. Alteration of a “contributing property” in the Historic District ✔✔✔✔If Residential
✔If Commercial
✔See Specifi c District
✔
2. Work on a “non-contributing” property in the Historic District ✔✔✔If Residential ✔If Commercial ✔See Specifi c District
✔
3. Work on an “individually listed National Register Property” in the Neighborhood Conservation Overlay District
✔✔✔✔If Residential
✔If Commercial
✔See Specifi c District
✔
4. Work on a “historically signifi cant property” in the Neighborhood Conservation Overlay District, but outside of the Historic District
✔✔✔✔If Residential
✔If Commercial
✔
5. Work on a “non-historically signifi cant” property in the Neighborhood Conservation Overlay District but outside of the Historic District
✔✔✔If Residential
✔If Commercial
✔
6. New infi ll and construction in the Neighborhood Conservation Overlay District, but outside the Historic District
✔✔✔If Residential
✔If Commercial
✔
7. New infi ll and construction in the Historic District*✔✔✔If Residential ✔If Commercial ✔✔AppendixChapter 5. District Specifi c Descriptions and GuidelinesChapter 4. Guidelines for Commercial Character AreasChapter 3. Guidelines for Residential Character AreasChapter 2. Design Guidelines for all PropertiesChapter 1: Rehabilitation Guidelines for Historic PropertiesIntroductionType of work:Chapter to use:600
14 Design Guidelines
4. Historically Signifi cant Property in the Conservation OverlayOther older buildings are found within the Conservation Overlay, but outside of any historic district. They are generally isolated buildings, in the context of newer structures, but sometimes they exist in a small grouping. These may be identifi ed at the time of application for COA approval. The conservation of the overall character of the building is the focus. The rehabilitation guidelines are therefore applied with some fl exibility. Focus is on maintaining the general form, character and materials, but more latitude in alterations is available. When such a building is in a context of similar construction, the rehabilitation guidelines will be applied more rigorously.
5. Non-historically Signifi cant Property in the Conservation OverlayThese are more recent properties, or older ones that are substantially altered, which lie within the Conservation Overlay, but outside of any historic district. For these, the design guidelines for all properties will apply, as well as those for specifi c building types (commercial or residential).
6. New Infi ll and ConstructionFor new projects within a historic district, the design guidelines for all properties will apply, as well as those for specifi c character areas and historic districts. The guidelines will be applied more rigorously in this case.
For new infi ll projects within the Conservation Overlay, but outside of any historic district, the design guidelines for all properties will apply, as well as those for specifi c character areas.
Please see the table on page 13 for a diagram of what guidelines apply to a project.
E. Policies underlying the design guidelines
The preservation principles outlined in Appendix C, as well as the following policies, should be considered when applying the design guidelines to historic properties in Bozeman.
The Secretary of the Interior’s Standards for the Rehabilitation of Historic PropertiesThe design guidelines incorporate principles set out in The Secretary of the Interior's Standards for the Treatment of Historic Properties with Guidelines for Preserving, Rehabilitating, Restoring and Reconstructing Historic Buildings, which are listed in Appendix B. These are a widely accepted set of general rehabilitation standards established by the National Park Service. These standards are policies that normally serve as a basis for more detailed rehabilitation guidelines. The City of Bozeman's Unifi ed Development Ordinance has adopted The Secretary of the Interior’s Standards as a basis for its standards for a COA. It is the intent of this document to be compatible with the Standards, while expanding on those basic preservation principles as they apply in Bozeman.
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Introduction 15
F. Components of Design Guidelines
Each chapter of the design guidelines contains the following components:
Design ElementThe fi rst is the design element category (e.g., streetscape elements, site planning, design element category (e.g., streetscape elements, site planning, design elementbuilding materials and secondary structures) under which the design guideline falls.
Policy StatementSecond is a policy statement explaining the Bozeman Department of Planning’s basic approach to treatment of the design element. This statement provides the basis for the more detailed design guidelines that follow underneath. In cases where special conditions in a specifi c project are such that the detailed design guidelines do not appear to address the situation, this general policy statement shall serve as the basis for determining the appropriateness of the proposed work. Policy statements are shown as large typeface statements.
Design GuidelinesThird is the design guideline statement itself, which is typically performance-design guideline statement itself, which is typically performance-design guideline statementoriented, describing a desired design treatment. The specifi c design guidelines are numbered and presented in bold face statements under each policy statement.
Additional InformationThe design guideline statement is followed by supplementary information that is treated as sub-points of the guideline. These sub-points may include additional requirements, or may provide an expanded explanation. These sub-points are listed as bulleted (•) statements.
A. Character-Defi ning Features
Policy: Historic features, including original materials, architectural details, window and door openings, contribute to the character of a structure and should be preserved when feasible. Continued maintenance is the best preservation method.
Guidelines1. Protect and maintain signifi cant stylistic features.• The best preservation procedure is to maintain historic features from the outset so that intervention is not required. • Preserve character-defi ning features. Then, repair only those features that are deteriorated. Finally, replace only those features that are beyond repair.Protect and maintain signifi cant stylistic features, such as this window detail.
✓
Detail of Design Guideline Components
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16 Design Guidelines
IllustrationsDesign guidelines are further explained through the use of photographs and illustrations. Examples given should not be considered the only appropriate options, but rather used as a guiding reference. In most instances, there are numerous possible solutions that meet the intention of the design guidelines, as well as the needs of the property owner.
In order to help the reader determine design approaches that are appropriate, many of the illustrations are marked with either a ✓ or an ✘. Those illustrations marked with a ✓ are considered appropriate solutions to the design issue, whereas those illustrations marked with an ✘ are not appropriate.
G. Applying for a Certifi cate of Appropriateness (COA)
A Certifi cate of Appropriateness, as its name implies, is a certifi cation that the design of a project is appropriate within the neighborhood or area in which it is located. It is required for any alteration, demolition or new construction in the Neighborhood Conservation Overlay District as defi ned in the UDO. Use the following steps for recommendations on how to proceed with a COA application:
Step 1. Consider Professional Design Assistance.Property owners are strongly encouraged to engage licensed architects and other design and planning professionals to assist them in developing their concepts. Doing so may facilitate a quick review process.
Step 2. Check Other City Regulations.The guidelines supplement other adopted Bozeman ordinances. The Department of Planning can provide information about these regulations, which also may affect the design character of a project. Examples include:
• The Bozeman Unifi ed Development Ordinance• The City of Bozeman 2020 Community Plan• Design Objectives Plan
Step 3. Become Familiar with the Design Guidelines.Review the basic organization of this guidelines document and determine which chapter(s) will apply to a project. The chart listed on page 13 is a great illustration to help see which chapters are applicable.
Step 4. Review the Site Context.Consider immediately adjacent properties and also the surrounding character of the project site. Understanding the desired character of the area is vital to the development of an appropriate design.
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Introduction 17
Step 5. Develop a Design Concept Using the Guidelines.The guidelines form the basis for the city’s design review decisions. Following the guidelines from the outset of the project will facilitate a smooth process.
Step 6. Preliminary Review (optional).Prepare materials for preliminary review by the Historic Preservation Offi ce prior to creating drawings for fi nal submittal. This step is highly recommended for new construction, accessory buildings and major alterations and additions. Even if preliminary material are not created, an initial meeting with City Staff is encouraged before an application is submitted.
Step 7. Prepare and Submit a Complete Application Packet for Formal Review.A complete application packet should be prepared, which includes the contents that are listed on the checklist form for a Certifi cate of Appropriateness, available at the Department of Planning and Community Development. A clear presentation of the proposed project to the City is necessary to obtain a COA. The presentation should focus on how the proposed project complies with these design guidelines and the standards set forth in the UDO. (See section 18.78.090 of the UDO.)
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CHAPTER 1REHABILITATION GUIDELINES FOR HISTORIC PROPERTIES
Original architectural details shall be preserved during rehabilitation.
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20 Design Guidelines
This chapter focuses on rehabilitation guidelines for historic buildings. The guidelines are divided into sections discussing the overall character-defi ning features, the materiality of those features and the individual building features. Guidelines also address specifi c issues in regards to historic residential and commercial building types, including additions.
In this Chapter:
A. Character-Defi ning Features B. Historic Building Materials C. Individual Building Features D. Rehabilitation of Historic Com-mercial PropertiesE. Rehabilitation of Historic Residen-tial PropertiesF. Secondary StructuresG. Adaptive Re-UseH. Historic Additions
By following the design guidelines presented in this document a homeowner can reasonably expect results similar to the before and after conditions shown here.
Before
After
✗
✓
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Protect and maintain signifi cant stylistic features, such as these porches, roof lines and window details.
Details such as these should be preserved in order to avoid the need for replacement in the future.
Historic features, including original materials, architectural details and window and door openings contribute to the character of a structure and are referred to as character-defi ning features.
CHAPTER 1REHABILITATION GUIDELINES FOR HISTORIC PROPERTIES
Design Guidelines:
A. Character-Defi ning Features
Policy: PreserveHistoric features, including original materials, architectural details and window and door openings contribute to the character of a structure and are referred to as character-defi ning features. They are often closely associated with specifi c architectural styles. They should be preserved when feasible. Continued main-tenance is the best preservation method.
Guidelines:1. Preserve and maintain significant stylistic and architectural features.• Porches, turned columns, brackets, exposed rafter tails and jigsaw ornaments, if historic, are examples of architectural features that should not be removed or altered. • The best preservation procedure is to maintain historic features from the outset so that intervention is not required. Employ preventive measures such as rust removal, caulking, limited paint removal and reapplication of paint. These should not harm the historic materi-als.• Maintain character-defi ning features. • Do not remove or alter architectural details that are in good condi-tion or that can be repaired.
2. Avoid adding elements or details that were not part of the original building.• For example, details such as decorative millwork or shingles should not be added to a building if they were not an original feature of that structure.
3. Protect architectural details from moisture accumulation that may cause damage.• Regularly check details that have surfaces which can hold moisture for long periods of time.
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22 Design Guidelines
Policy: RepairIn some cases, original architectural details may be deteriorated. Horizontal surfaces such as chimney caps and window sills are likely to show the most deterioration because they are more exposed to weather. When deterioration occurs, repair the material and any other related problems. It is also important to recognize that all details weather over time and that a scarred fi nish does not represent an inferior material, but simply refl ects the age of the building. Therefore, preserving original materials and features that show signs of wear is preferred to replacing them.
Guidelines:4. Repair only those features that are deteriorated. • Patch, piece-in, splice, consolidate or otherwise upgrade existing materials, using recognized preservation methods.• Isolated areas of damage may be stabilized or fi xed using consoli-dants. Epoxies and resins may be considered for wood repair. • Removing damaged features that can be repaired is not appropri-ate. • Protect features that are adjacent to the area being worked on.
5. When disassembly of a historic element is necessary for its restoration, use methods that minimize damage to the original materials.• When disassembly of a historic feature is required during restoration, document its location so it may be repositioned accurately. Always devise methods of replacing disassembled details in their original confi guration.
6. Use technical procedures for cleaning, refi nishing and repairing architectural details that will maintain the original fi nish.• Consult with the City of Bozeman for techniques that are generally considered appropriate.• When choosing preservation treatments, use the gentlest means possible that will achieve the desired results.• Employ treatments such as rust removal, caulking, limited paint removal and reapplication of paint or stain.
Policy:ReplaceWhile restoration of the original feature is the preferred alternative, in-kind replacement is also an option. In the event replacement is necessary, the new material should match that being replaced in design, color, texture and other visual qualities. Replacement should occur only if the existing historic material is beyond repair.
After: A successful preservation effort will result in a product shown in the example above.
Before: A deteriorated railing should be repaired, rather than replaced.
When disassembly of a historic feature is required in a restoration procedure, document its location so that it may be repositioned accurately.
✓
✗
✓
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Chapter 1 23
Replace missing original details in kind.
Where replacement of an element is required, remove only those portions that are deteriorated beyond repair.
Replacement
piecepiece✓
Guidelines:7. Replacement of missing or deteriorated architectural elements should be accurate.• The design should be substantiated by physical or pictorial evidence to avoid creating a misrepresentation of the building’s history.• Use the same kind of material as the original when feasible. How-ever, a substitute material may be acceptable if the size, shape, texture and fi nish conveys the visual appearance of the original.
8. When reconstruction of an element is impossible, develop a new design that is a simplifi ed interpretation of it.• This is appropriate when inadequate information exists to allow for an accurate reconstruction.• The new element should be similar to comparable features in general size, shape, texture, material and fi nish.
B. Historic Building Materials
Policy:Primary historic building materials should be preserved in place whenever fea-sible. When the material is damaged, then limited replacement which matches the original, should be considered. Primary historic building materials should never be covered or subjected to harsh cleaning treatments.
Refer to the city for an appropriate material resources for the rehabilitation of historic properties.
Guidelines:1. Preserve original building materials.• Avoid removing siding that is in good condition or that can be repaired in place.• Remove only siding which is deteriorated, and must be replaced.• Masonry features that defi ne the overall historic character, such as walls, cornices, pediments, steps and foundations, should be preserved.• Avoid rebuilding a major portion of exterior masonry walls that could be repaired. Reconstruction may result in a building which is no longer historic.
2. Protect wood features from deterioration.• Provide proper drainage and ventilation to minimize rot.• Maintain protective coatings to retard drying and ultraviolet damage. If the building was painted originally, it should remain painted.
Protect wood siding and other wood surfaces with a painted fi nish.
610
24 Design Guidelines
3. Plan repainting carefully.• Always prepare a good substrate. Remove damaged or deteriorated paint only to the next intact layer, using the gentlest means possible, prior to painting.• Use compatible paints. Some latex paints will not bond well to earlier oil-based paints without a primer coat.
4. Brick or stone that was not painted historically should not be painted.• Masonry naturally has a water-protective layer, or patina, to protect it from the elements. Painting masonry walls can seal in moisture already in the masonry; thereby not allowing it to breathe and caus-ing extensive damage over the years.
5. Repair deteriorated primary building materials by patching, piecing-in, consolidating or otherwise reinforcing the material.• Avoid the removal of damaged materials that can be repaired.• Isolated areas of damage may be stabilized or fi xed, using consoli-dants. Epoxies and resins may be considered for wood repair and special masonry repair components also may be used.
6. Repoint mortar joints where there is evidence of deterioration.• Duplicate the old mortar in strength, composition, color and tex-ture.• Avoid using mortar with a high portland cement content, which will be substantially harder than the original.• Duplicate the mortar joints in width and profi le.
7. Use the gentlest means possible to clean the surface of a structure.• Perform a test patch to determine that the cleaning method will cause no damage to the material surface. Many procedures can actually have an unanticipated negative effect upon building materials and result in accelerated deterioration or a loss of character. • Harsh cleaning methods, such as sandblasting, can damage the historic materials, changing their appearance. Such procedures are inappropriate.• If cleaning is appropriate, a low pressure water wash is preferred. Chemical cleaning may be considered if a test patch is fi rst reviewed and negative effects are not found.
8. Match the original material in composition, scale and fi nish when replacing materials on primary surfaces.• If the original material is wood clapboard, for example, then the replacement material should be wood as well. It should match the original in size, the amount of exposed lap and in fi nish.• Replace only the amount required. If a few boards are damaged beyond repair, then only they should be replaced, not the entire wall.
✓
When reconstruction of an element is impossible, develop a new design that is a simplifi ed interpretation of it.
Do not remove damaged materials that can be repaired. In this case, loose shingles may be re-secured while missing ones may be replaced.
Use approved technical procedures for cleaning, refi nishing and repairing historic materials. Harsh cleaning methods, such as sandblasting, can damage the historic materials and change their appearance.
✗
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Chapter 1 25
9. Do not use synthetic materials, such as aluminum or vinyl siding or panelized brick, as replacements for primary building materials.• In some instances, substitute materials may be used for replacing architectural details, but doing so is not encouraged. If it is neces-sary to use a new material, such as a fi berglass column, the style and detail should match that of the historic model. • Primary building materials, such as wood siding and brick, should not be replaced with synthetic materials.• Modular materials should not be used as replacement materials. Synthetic stucco and panelized brick, for example, are inappropri-ate.
10. Covering original building materials with new materials is inappropriate. • Vinyl siding, aluminum siding and new stucco are inappropriate on historic buildings. Other imitation materials that are designed to look like wood or masonry siding, but that are fabricated from other materials, are also inappropriate.• If a property already has a non-historic building material covering the original, it is not appropriate to add another layer of new mate-rial, which would further obscure the original.
11. Consider removing later covering materials that have not achieved historic signifi cance.• Once the non-historic siding is removed, repair the original, under-lying material. • If a house has a stucco fi nish, removing the covering may be dif-fi cult, and may not be desirable. Test the stucco to assure that the original material underneath will not be damaged.
Consider removing later covering materials that have not achieved historic signifi cance. Compare the left photo with the photo on the right, after the synthetic siding was removed. Note how the lap dimensions on the original siding are much smaller.
✗✓✗
Commence with building cleaning after any repointing has completely cured.
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26 Design Guidelines
C. Individual Building Features
Windows
Policy:The character-defi ning features of an historic window and its distinct materi-als and placement should be preserved. In addition, a new window should be in character with the historic building. This is especially important on primary facades.
Guidelines1. Preserve the functional and decorative features of a historic window.• Features important to the character of a window include its frame, sash, muntins, mullions, glazing, sills, heads, jambs, moldings, operation and groupings of windows. Repair frames and sashes rather than replacing them, whenever conditions permit.• Window awnings and shutters are appropriate in limited circum-stances. They are only appropriate on specifi c architectural styles and commercial building types. Shutters were found on colonial style buildings.
2. Preserve the position, number and arrangement of historic windows in a building wall.• Enclosing a historic window opening in a key character-defi ning facade is inappropriate, as is adding a new window opening. This is especially important on primary facades where the historic ratio of solid-to-void is a character-defi ning feature. • Greater fl exibility in installing new windows may be considered on rear walls.
3. Preserve the size and proportion of a historic window opening.• Reducing an original opening to accommodate a smaller window or increasing it to receive a larger window is inappropriate.
4. Preserve the historic ratio of window openings to solid wall on a primary facade.• Signifi cantly increasing the amount of glass on a character-defi ning facade will negatively affect the integrity of the structure.
5. Match a replacement window to the original in its design.• If the original is double-hung, then the replacement window should also be double-hung, or at a minimum, appear to be so. Match the replacement also in the number and position of glass panes. • Matching the original design is particularly important on key char-acter-defi ning facades.
✗
If stucco covers original siding, then its removal is encouraged.
Repair wood features by patching or piecing-in new wood elements that match the original.
✓
Protect and maintain the stylistic features and proportions of a historic window opening.
✓
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6. In a replacement window, use materials that appear similar to the original.• Using the same material as the original is preferred, especially on character-defi ning facades. However, a substitute material may be considered if the appearance of the window components will match those of the original in dimension, profi le and fi nish.
7. Match, as closely as possible, the profile of the sash and its components to that of the original window.• A historic wood window has a complex profi le. Within the window's casing, the sash steps back to the plane of the glazing (glass) in several increments. These increments, which individually only measure in eighths or quarters of inches, are important details. They distinguish the actual window from the surrounding plane of the wall.
8. Use a storm window to enhance energy conservation rather than replace a historic window.• Install a storm window on the interior, when feasible. This will al-low the character of the original window to be seen from the public way. • If a storm window is to be installed on the exterior, match the sash design of the original windows. A metal storm window may be ap-propriate if the frame matches the proportions and profi les of the original window. It should fi t tightly within the window opening without the need for sub-frames or panning around the perimeter. Match the color of the storm window sash with the color of the window frame; do not use an anodized or a milled (a silvery metal-lic) fi nish. Finally, set the sash of the storm window back from the plane of the wall surface as far as possible.
Protect and maintain stylistic features and proportions of a historic window opening.
✗
Preserving the proportions of a historic structure helps ensure continuity within a district.
✓
The appearance of the window components should match those of the original in dimension, profi le and fi nish. Typical primary window types seen on historic structures.
✓
✓
2
1
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28 Design Guidelines
Doors
Policy:The character-defi ning features of a historic door and its distinct materials and placement should be preserved. In addition, a new door should be in character with the historic building. This is especially important on primary facades.
Guidelines:9. Preserve the decorative and functional features of a primary entrance.• Maintain features important to the character of a historic doorway. These may include the door, door frame, screen door, threshold, glass panes, paneling, hardware, detailing, transoms and fl anking sidelights. • Avoid changing the position and function of original front doors and primary entrances.
10. Maintain the original proportions of a signifi cant door.• Altering its size and shape is inappropriate.
11. When a historic door is damaged, repair it and maintain its general historic appearance.
12. When replacing a door, use materials that appear similar to that of the original. • A metal door, if seen from the street, is inappropriate where the original was wood.
13. When replacing a door, use a design that has an appearance similar to the original door, or a door associated with the style of the house or commercial building.• Very ornate doors are discouraged, unless photographic evidence can support their use.
14. If energy conservation and heat loss are a concern, consider using a storm door instead of replacing an historic entry door on a resi-dential building.• Generally, wood storm doors are most appropriate.• A metal storm door may be appropriate if it is simple in design and if the frame is painted so that raw metal is not visible.
Typical primary door types seen on historic residential structures.
Paneled
Door with
glass panes
Half Glass
Door
Period Revival
Door
Craftsman
Door
Colonial
Revival
Door with
transom and
sidelights
Paneled
Door
Preserve the decorative and functional features of a primary door.
If a door requires replacement keep the original door proportions.
✗
✓
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Chapter 1 29
Roofs
Policy:The character of a historical roof should be preserved, including its form and materials, whenever feasible.
Guidelines:15. Preserve the original roof form of a historic structure.• Avoid altering the angle of a historic roof. Instead, maintain the perceived line and orientation of the roof as seen from the street. • Retain and repair roof detailing.
16. Preserve the original eave depth of a historic structure.• The shadows created by traditional overhangs contribute to one's perception of the building's historic scale and therefore, these over-hangs should be preserved. Cutting back roof rafters and soffi ts or in other ways altering the traditional roof overhang is therefore inappropriate.
17. Minimize the visual impacts of skylights and other rooftop devices.• The addition of features such as skylights or solar panels should not be installed in a manner such that they will interrupt the plane of the historic roof. They should be lower than the ridgeline. • Flat skylights that are fl ush with the roof plane may be considered on the rear and sides of the roof. Locating a skylight or a solar panel on a front roof plane should be avoided.
18. When planning a rooftop addition, preserve the overall appearance of the original roof.• An addition should not interrupt the original cornice or ridgeline.
19. Preserve original roof materials.• Avoid removing historic roofi ng material that is in good condition. When replacement is necessary, use materials that are similar to the original in both style as well as physical qualities and use a color that is similar to that seen historically. • Specialty materials such as tile, slate or concrete should be replaced with a matching material.
20. Avoid using conjectural materials or features on a roof.• Adding a widow's walk (an ornate railing around the roof ridge) on a house where there is no evidence that one existed creates a false impression of the home's original appearance, and is inappropriate, for example.
Typical Residential Roof Types
Clipped Gable roof
Shed roof
Gabled roof
Gambrel roof
Cross-Gabled roof
Mansard roof
Hipped roof
Flat roof
Continuing the traditional roof line will preserve the integrity of the historic district.
Flat roofed buildings are commonly found in the downtown district.
✓
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30 Design Guidelines
21. New or replacement roof materials should convey a scale and texture similar to those used traditionally.• Composite shingles work best for many types of buildings.• Roof materials should be generally earth tones and have a matte, non-refl ective fi nish.• When choosing a roof replacement material the architectural style of the structure should be considered.
22. If they are to be used, metal roofs should be applied and detailed in a manner that is compatible with the historic character and does not distract from the historic appearance of the building.• Metal roof materials should be earth tones and have a matte, non-refl ective fi nish.• Seams should be of a low profi le.• The edges of the roofi ng material should be fi nished similar to those seen historically. The edges of standing seam metal roof were simply bent downward at the edges of the roof with a very slight overhang. In most cases the gutters hide this detail.• Note that metal roofs work best on homes with front-facing gable roofs, small homes and/or homes with simple roof forms.• Stamped metal panels should appear similar to those seen histori-cally.• Many modern metal roofi ng materials do not have proportions that are appropriate to the historic character of many local neighbor-hoods.
Foundations
Policy: There is one policy for the preservation of building foundations that serves as the basis for all related design guidelines and supporting information. The City will use this policy and associated design guidelines in making its decisions for a Certifi cate of Appropriateness. In cases where special conditions of a specifi c project are such that the detailed design guidelines do not appear to address the situation, this general policy statement will serve as the basis for determining the appropriateness of the proposed work. Keeping moisture away from a founda-tion is the primary objective.
Guidelines:23. Vines and other plants should not be allowed to grow on foundation walls.• Plants tend to retain moisture and keep damp walls from drying. • Weeds and shrubs should not be allowed to come in contact with foundation walls. • Avoid piling items such as fi rewood, trash, or mulch against a foundation wall, since these can hold moisture too and let it into the wall.
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24. If the foundation walls have ventilation openings, be sure these are kept clear.• These help the walls dry out after getting wet (they also help keep moisture from building up in basements and crawl spaces). • Ventilation openings or basement windows should not be fi lled in with permanent materials such as brick or concrete block; try wood or metal panels in place of window glass if windows must be blocked up, but retain the wood or metal framing and sash.
25. Make sure the soil or pavement next to the foundation wall slopes away and not toward the wall.• Provide positive drainage away from foundations to minimize rising moisture.• This will keep water from soaking down into the wall and surround-ing soil. Wet soil can lose its weight-supporting capacity and result in foundation and wall cracks. • Watch for open joints between pavement and foundation wall where water fl owing down the wall can get into the soil.
26. Gutters and downspouts should not be clogged or leaking and should carry water away from the foundation wall. • During heavy rains, watch to see if water is fl owing or dripping down the building wall and into the foundation. • Downspouts should be connected to underground drains if possible (check to be sure these are clear, too), or at least should empty onto splash blocks which carry the water away from the foundation wall.
27. Avoid cutting new window and door openings in foundation walls, or enlarging existing ones. • This can weaken the foundation signifi cantly. If you need to make these alterations, get qualifi ed advice on how the foundation will be affected.
28. Avoid covering foundations with inappropriate materials. • Materials such as composite “brick” wallpaper diminish the char-acter of the structure.• These coverings can also hold moisture in the foundation wall and cause damage to the structure.
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32 Design Guidelines
D. Rehabilitation of Historic Commercial Properties
Preservation of Commercial Storefronts
Policy:Many storefronts in Bozeman have components seen traditionally on commercial buildings. The repetition of these standard elements creates a visual unity at the street that should be preserved.
Guidelines:1. For a commercial storefront building, a rehabilitation project should preserve these character-defi ning elements:• Display windows: The main portion of glass on the storefront, where goods and services are displayed.• Transom: The upper portion of the display window, separated by a frame.• Kickplate: Found beneath the display window. Sometimes called a bulk-head panel.• Entry: Usually set back from the sidewalk in a protected recess.• Upper-story windows: Windows located above the street level. These usually have a vertical orientation.• Cornice molding: A decorative band at the top of the building. • These features should not be altered, obscured or removed.• This will help maintain the interest of the street to pedestrians by pro-viding views to goods and activities inside fi rst fl oor windows.
2. If a storefront is altered, restoring it to the original design is preferred.• If evidence of the original design is missing, use a simplifi ed inter-pretation of similar storefronts.• Historic photographs of Bozeman and its commercial buildings are widely available and should be used when determining the original character of a storefront design.
3. Alternative designs that are contemporary interpretations of traditional storefronts may be considered where the historic facade is missing and no evidence of it exists.• Where the original is missing and no evidence of its character ex-ists, a new design that uses the traditional elements may be consid-ered.• However, the new design should continue to convey the character of typical storefronts, including the transparent character of the display window.• Greater fl exibility in treatment of rear facades is appropriate. How-ever, care should be taken to preserve storefronts on those buildings which have traditional commercial storefronts on more than one facade, such as a corner building.
This is an appropriate addition to the rear of a historic commercial building.
✓
✓
These images show buildings with alternative designs that are appropriate interpretations of a traditional storefront.
✓
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Chapter 1 33
Preserve the historic character of a storefront when it is intact.
4. Retain the kickplate as a decorative panel.• The kickplate, located below the display window, adds interesting detail to the streetscape and should be preserved.• If the original kickplate is covered with another material, consider exposing the original design.
5. If the original kickplate is missing, develop a sympathetic replacement design.• Wood is an appropriate material for replacements on most styles. However, ceramic tile and masonry may also be considered when appropriately used with the building style.
6. Preserve the character of the cornice line.• Most historic commercial buildings have cornices to cap their facades. Their repetition along the street contributes to the visual continuity on the block.• Many cornices are made of sheet metal, which is fairly lightweight and easy to repair. Areas that have rusted through can be patched with pieces of new metal.
Typical commercial components.
pediment
cornice
upper story upper story upper
windowsstory windowsstory
midbeltcornice
transom
display windowdisplay windowdisplay
piers
recessedentry
kickplate
Traditional Main Street building facade.
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34 Design Guidelines
7. Reconstruct a missing cornice when historic evidence is available.• Use historic photographs to determine design details of the original cornice.• Replacement elements should match the original in every detail, especially in overall size and profi le. Keep sheet metal ornamenta-tion well painted.• The substitution of another old cornice for the original may be considered, provided that the substitute is similar to the original.
8. A simplifi ed interpretation is also appropriate for a replacement cornice if evidence of the original is missing.• Appropriate materials include stone, brick and stamped metal.
9. Retain the original shape of the transom glass in historic storefronts.• Transoms, the upper glass band of traditional storefronts, introduced light into the depths of the building, saving on light costs. These bands should not be removed or enclosed.• The shape of the transom is important to the proportion of the storefront, and it should be preserved in its historic confi guration. • If the original glass is missing, installing new glass is preferred. However, if the transom must be blocked out, be certain to retain the original proportions. One option might be to use it as a sign panel or decorative band.
10. A parapet wall should not be altered, especially those on primary elevations or highly visible facades. • When a parapet wall becomes deteriorated, there is sometimes a temptation to lower or remove it. Avoid doing this because the fl ashing for the roof is often tied into the parapet, and disturbing it can cause moisture problems. • Inspect parapets on a regular basis. They are exposed to the weather more than other parts of the building, so watch for deterioration such as missing mortar or excessive moisture retention. • Avoid waterproofi ng treatments, which can interfere with the parapet’s natural ability to dry out quickly when it gets wet.
When the reconstruction of an element is impossible, a simplifi ed interpretation is also appropriate.
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Additions to Commercial Properties
Policy:Three distinct types of additions to historic commercial buildings may be con-sidered. First, a ground-level addition that involves expanding the footprint of a structure may be considered. Such an addition should be to the rear or side of a building. This will have the least impact on the character of a building, but there may only be limited opportunities to do this.
Second, an addition to the roof may be designed that is simple in character and set back substantially from the front of a building. In addition, the materials, window sizes and alignment of trim elements on the addition should be compat-ible to those of the existing structure.
A third option, which only will be considered on a case-by-case basis, is to design an addition within the wall plane of the existing building. This option is the most diffi cult and requires the most care to respect the relationship of the building to the street. Such an addition should provide a visual distinction between the existing structure and its addition. This may be accomplished through the use of a belt course element or a subtle change in building materials.
Guidelines:11. An addition should be compatible in scale, materials and character with the main building.• An addition should relate to the building in mass, scale and form. It should be designed to remain subordinate to the main structure. • An addition with a pitched roof is inappropriate for a building with a fl at roof. • An addition to the front of a building is inappropriate.
12. An addition should not damage or obscure architecturally important features.• For example, loss or alteration of a cornice line should be avoid-ed.
13. An addition may be made to the roof of a building if it does the following:• An addition should be set back from the primary, character-defi n-ing facade, to preserve the perception of the historic scale of the building.• Its design should be modest in character, so it will not attract atten-tion from the historic facade.• The addition should be distinguishable as new, albeit in a subtle way.
An original three-story building, before an addition. Compare with sketches below.
New addition to the side
New addition to the rear
Appropriate alternative approaches to additions.
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36 Design Guidelines
14. In limited circumstances, an addition may be made to the roof of a building and not be set back from character-defi ning facades, if it does the following:• An addition should be distinguished from the existing building. A change in material or a decorative band can be considered to ac-complish this.• An addition should maintain the alignment of storefront elements, moldings, cornices and upper-story windows that exist on the main part of the building.• The addition should also be compatible in scale, texture and materi-als with the original.
Signs
Policy:Historically, signs that were mounted and/or painted on the exterior of a build-ings advertised the primary business conducted there. Many of these signs still stand today and should be preserved when feasible.
Guideline:15. Preserve an historic sign where it exists, when feasible.
E. Rehabilitation of Historic Residential Properties
Porches
Policy:PreservePreserve a porch in its original condition and form.A porch is one of the most important character-defi ning elements of a facade. Porches help to provide visual interest to a building, and can infl uence its perceived scale, protect entrances and pedestrians from rain and provide shade in summer.
Guideline:1. Maintain an original porch, when feasible.• Maintain the existing location, shape, details and posts of the porch. • Missing or deteriorated decorative elements should be replaced to match existing elements; e.g., match the original proportions and spacing of balusters when replacing missing ones. • Avoid using a porch support that would be substantially smaller than other supports on the porch or than that seen historically.• Do not remove an original porch from a building.
2. Enclosing a porch with opaque materials that destroy the openness and transparency of the porch is inappropriate.• Where a porch must be enclosed, use transparent materials (such as glass) and place them behind the balusters and balustrade to preserve the visual character of the porch.
Preserve an original porch. Avoid using a porch support that would be substantially smaller than other supports on the porch or than seen historically.
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Any new additions should not take away from the original historic structure. An addition on the back of a structure is acceptable.
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While a simple design solution, the use of metal pipes as replacement porch rails is inappropriate.
✗3. Where building codes stipulate that new porch railings lower than 36 inches in height be augmented or corrected to raise their effec-tive height to 36 inches, consider the following:• Provide a smaller railing above the historic railing to achieve a greater overall railing height.
Policy:RepairRepair a deteriorated porch instead of removing or replacing it. The preferred treatment for an altered porch is to repair it, rather than replace it altogether. This approach is preferred because the original materials contribute to its his-toric character. Even when replaced with an exact duplicate, a portion of the historic building fabric is lost; therefore, such treatment should be avoided when feasible.
Guidelines:4. Repair those elements of a porch that are deteriorated. • Removing damaged materials that can be repaired is not appropri-ate.
5. Consider restoring an altered porch back to its original design and confi guration. • If the historic design of the porch is unknown, then base the design of the restoration on other traditional porches on buildings of a similar architectural style.• If the original porch steps have been replaced with concrete, consider restoring them to their original, wood condition. If termite control is of concern, then consider only making the bottom step concrete and not the entire stair assembly.
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The porch on the left has experienced an inappropriate alteration; enclosed railing. Compare it with its “rehab” in the photo to the right.
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38 Design Guidelines
Policy:ReplaceReplace a missing porch with one that appears similar to that seen historically. When a porch is to be replaced, the fi rst step is to research the history of the house to determine the appearance and materials of the original porch. The most important aspects of a replacement design are its location, scale and materials. Unless reconstructing a porch from historical documentation, it is not neces-sary to replicate the details of the original porch or a porch design copied from a similar style house. However, it is important that new details be compatible (similar form, scale and materials) for the design of the porch and the style of the house.
Guidelines:6. When porch replacement is necessary, it should be similar in character, design, scale and materials to those seen traditionally.• The size of a porch should relate to the overall scale of the primary structure to which it is attached.• Base the design of a replacement porch on historical documentation if available.• Where no evidence of the historic porch exists, a new porch may be considered that is similar in character to those found on comparable buildings.
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Existing Condition: A folk or vernacular style house with the original porch removed.
Preferred Approach, when historical documentation is available: A folk or vernacular style house with a replacement porch designed similar to that seen historically.
Acceptable Approach, when historical documentation is not available: A folk or vernacular style house with a simplifi ed interpretation of a traditional porch design.
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Existing Condition: Craftsman style house with an enclosed porch.Preferred Approach,when historical documentation is available: Craftsman style house with a replacement porch designed similar to that seen historically.
Acceptable Approach, when historical documentation is not available: Craftsman style house with a simplifi ed interpretation of a traditional porch design.
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7. Porch supports should be of an appropriate size to compliment the entry and existing structure.• Wood columns are best for most structures in Bozeman.• Brick or stone may be appropriate for some architectural styles.• See the style section of the guidelines for further recommenda-tions.
8. A porch should use similar materials to that seen historically.• Use materials similar to those seen historically. Wood decking, steps, balustrades and porch supports were most common.• While matching original materials is preferred, when detailed correctly and painted appropriately, fi berglass columns may be considered.• Do not replace a wood porch decking and steps with concrete.
Additions to Residential Properties H
Policy:When planning an addition to an existing building, consider the effect it will have on the structure. The following guidelines avoid any negative impacts of an addition: While the choice of a style is not a concern of these principles, there is an awareness that each property has some style that helps defi ne its character. Additions that refl ect elements of the existing predominant style reinforce the positive character. Those elements that seem unintentionally foreign to the in-dividual property and detract from the overall design should be minimized and not considered positive elements to base the design of an addition on.
Guidelines:9. The loss of historically signifi cant features, where they exist, should be minimized.• When preserving original details and materials, follow the guidelines at the beginning of this chapter.
10. Place an addition at the rear of a building or set it back from the front to minimize the visual impacts.• This will allow the original proportions and character to remain prominent.• A roof top addition should be set back at least 10 feet from a primary facade.
Consider providing a smaller railing above the historic railing to achieve a greater overall railing height.
✓new rail
This detail shows ornate rafters which should be preserved during a rehabilitation process.
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40 Design Guidelines
11. A new addition should respect the mass and scale of the original structure. • While a smaller addition is visually preferable, if the addition would be signifi cantly larger than the original building, one option is to separate it from the primary building, when feasible, and then link it with a smaller connector.• In some cases, adding vertically, through construction of dormers, will help to minimize the impacts of additions and preserve rear yards.• A new addition should fi t within the range of stories that help defi ne the character of the neighborhood.• For a larger addition, break up the mass of the addition into smaller modules that relate to the historic house.• An addition should be simple in design to prevent it from competing with the primary facade.
12. The roof form of a new addition should be in character with and subordinate to that of the primary building.• It is important to repeat the roof lines and slopes found on the pri-mary structure. Typically, gable, hip and shed roofs are appropriate for residential-type building additions. Flat roofs may be appropriate for commercial buildings or International style structures.
13. When constructing a rooftop addition, keep the mass and scale subordinate to the primary building.• The addition should not overhang the lower fl oors of the primary building.
14. When adding a dormer, it should be in character with the primary structure’s design.• A dormer should be subordinate to the overall roof mass and should be in scale with ones on similar historic structures.• The dormer should be located below the ridge line of the primary structure.• The number and size of dormers should not visually overwhelm the scale of the primary structure.• Dormers are typically added to a structure to increase the amount of headroom in upper fl oors. Traditionally, dormers are designed as smaller elements. If signifi cant increases in space are desired, do not consider oversized dormers. Rather, develop an addition to the rear of a structure.
15. Raising a building may be considered only if signifi cant features are preserved.• The historic porch design must remain intact.• Minor alterations to porch stairs may be considered, but the overall design must be preserved.• Window and door locations and alignments should remain intact.
These additional structures are set back from the facade of the original historic home.
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This addition is set back behind the original structure and the new addition is accessed by a connector.
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This roof top addition is not subordinate to the existing structure.
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F. Secondary Structures
Policy:Preserving the historic fabric along an alley in a historic district is important. This includes sheds, garages and carriage houses. They are traditionally subordinate in scale and character to the primary structure and are typically located to the rear of the lot. These features should be retained.
Guideline:1. Preserve an existing secondary structure when feasible.• Retain original materials when feasible.• Maintain the subordinate character of the structure also.
G. Adaptive Re-Use
Policy:Converting a building to a new use that is different from that which its design refl ects is considered to be “adaptive re-use.” For example, converting a residen-tial building to an offi ce is adaptive re-use. A good adaptive re-use project retains the historic character of the building while accommodating its new function.
Guideline:1. Seek uses that are compatible with the historic character of the building.• Building uses that are closely related to the original use are preferred. An example would be the conversion of a residential-type building to an offi ce. This can be accomplished without radical alterations to either the interior or exterior of the structure.• Avoid altering porches and original windows and doors.
H. Historic Additions
Policy:Some early additions may have taken on historic signifi cance of their own. One constructed in a manner that was compatible with the original building and that is associated with the period of signifi cance may merit preservation in its own right, these additions should be evaluated.
In contrast, more recent additions that detract from the character of the building should be considered for removal.
Guideline:1. Preserve an older addition that has achieved historic signifi cance in its own right.• For example, a porch or a kitchen wing may have been added to the original building early in its history. Such an addition is usually similar in character to the original building in terms of materials, fi nishes and design.
This building has been successfully adapted from a single-household home to a bed and breakfast in the Bozeman Brewery Historic District.
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CHAPTER 2DESIGN GUIDELINES FOR ALL PROPERTIES
Appropriate new infi ll building for the commercial character area.
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44 Design Guidelines
In this Chapter:
A. TopographyB. Street PatternsC. AlleysD. StreetscapeE. Landscape DesignF. Building FormG. Solid-to-Void RatioH. MaterialsI. Architectural CharacterJ. ParkingK. BuffersL. Site LightingM. Utilities and Services
This chapter covers design guidelines for all properties. It includes a variety of topics that may arise in rehabilitation projects, new build-ing designs and site improvements.
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CHAPTER 2 DESIGN GUIDELINES FOR ALL PROPERTIES
A. Topography
Policy:Site work should be planned to protect the assets of the existing topography.
Guidelines:1. Minimize cut and fi ll on a site. • Divide large grade changes into a series of benches and terraces, where feasible.
2. Design a building foundation to conform to the existing topography, rather than creating extensive cut and fi ll. • Step the foundation of a building to follow site contours, when feasible. • If stepping the foundation is not possible, disguise the cut with building placement and/or building walls, and provide a landscape buffer system at the top of cut.
3. Minimize the visual impacts of cut and fi ll on a site. • Regrade the site as a stable, “natural” slope, when feasible.
B. Street Patterns
Policy:Historic settlement patterns seen in street and alley plans often contribute to the distinct character of the historic district and therefore they should be preserved. These street plans infl uence the manner in which primary structures are sited and they also shape the manner in which secondary structures and landscape features may occur on the site.
Guidelines:1. Respect historic settlement patterns.• Site a new building such that it is arranged on its site in a way simi-lar to historic buildings in the area. This includes consideration of building setbacks and open space.
Where there is uniform alignment, a new building should match the existing build-ings on a block. In other cases, where there is a narrow range of variation in setback, then new building may fi t within that es-tablished range.
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Established
setback range
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46 Design Guidelines
C. Alleys
Policy:Alleys accommodate service functions and provide pedestrian connections and secondary vehicle access. All alleys, both paved and unpaved, contribute to the character of the district.
Guidelines:1. Unpaved lanes contribute to the distinct character of the neighborhood; therefore, they should continue in their "rustic" state, when feasible.• In some instances where it is necessary to keep dust levels down, and it is necessary to pave the alley, recycled asphalt is the preferred material.
2. The traditional scale and width of alleys should be continued. • Maintain the traditional character and scale of an alley by locating buildings and fences along the alley edges to maintain the alley edge.
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The traditional scale and width of alleys can be viewed in this 1940 photograph. Note the secondary structures that line the alley edge, much like they do today. (Photo credit: Gallatin County Historical Society)
Maintain the traditional character of the streetscape. The character changes be-tween commercial and residential areas. In commercial areas street trees, light fi xtures and furnishings accent the public sidewalk. In residential areas planting strips are typically found between the curb and sidewalk.
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D. Streetscape
Policy: Maintain the traditional character of the streetscape. This includes a rich col-lection of varying street designs, sidewalk types and street trees.
Guidelines:1. Maintain the variety of street paving designs.• Most streets in the neighborhood are paved and have both curb and gutter. However, some streets lack sidewalks or paving. Thus, they possess their own character and serve as informal pedestrian ways. This tradition of unpaved streets should continue when it is not a hazard to pedestrians or bicyclists.
2. Maintain the variety of sidewalk designs.• Where a detached (sidewalks separated from the street by a strip of grass) sidewalk exists, it should be preserved.• Where no sidewalk exists a new sidewalk is required; it should be constructed to be in character with the traditional sidewalks in the neighborhood.
3. Continue the use of planting strips.• Planting strips should act as a transition between public and semi-public spaces. • Where planting strips between the curb and sidewalk exist they should be maintained.• If new detached sidewalks are installed in the neighborhood, new planting strips should be provided.
4. Continue the pattern of street trees in a block. Because street trees serve various aesthetic and practical functions, they should be maintained. • Existing street trees should be preserved, when feasible. • If a new detached sidewalk is to be created, street trees should be an accompanying feature.• If a new sidewalk is to be installed, it should detour around mature street trees, when feasible.• When an existing street tree dies, it should be replaced.• Any new developments should include street trees.• The historic urban design character for street tree placement should be considered when enforcing city street standards.
Streetscapes such as these should be con-tinued throughout the neighborhoods. No-tice the lack of fences in the front yards and the use of sidewalks and planting strips.
Bozeman should preserve the mature trees that line the street.
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Continue the pattern of street trees in resi-dential neighborhoods.
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Front yard
Detached sidewalkDetached sidewalk
Planting strip
StreetStreet
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48 Design Guidelines
E. Landscape Design
Policy:Traditionally, plant beds were located around building foundations, along walkways and sometimes in front of fences. Some of these plantings may have historic signifi cance and should be retained, to the extent feasible. Some mature trees may also contribute to the historic landscape and should be preserved.
Guidelines:1. Preserve and maintain mature trees and signifi cant vegetation within all corridors.• Include existing vegetation as a part of a landscape design scheme where appropriate. • In development areas, healthy trees and vegetation clusters should be identifi ed for preservation. Special consideration should be given to mature trees, 6” or greater in diameter, and to vegetation clusters with signifi cant visual impact. Vegetation designated for preserva-tion should be incorporated into new development site design to the maximum extent possible.
F. Building Form
Policy:A similarity of building forms also contributes to a sense of visual continuity. In order to maintain this sense of visual continuity, a new building should have basic roof and building forms that are similar to those seen traditionally. Overall facade proportions also should be in harmony with the context.
Guidelines:1. Use building forms that are similar to those seen traditionally on the block.• Simple rectangular solids are typically appropriate.
2. Exotic building and roof forms that would detract from the visual continuity of the street are discouraged.• Geodesic domes and A-frames are not generally considered tra-ditional building forms and should not be used in the designated historic districts.• Sloping roof forms such as gable and hip roofs are appropriate in most residential and transition areas.• Flat roofs are appropriate in most commercial and transition areas, and in some cases may be appropriate in residential areas.
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Notice the traditional gabled roof used as well as the porch; these make up the overall building form.
✘
Avoid using exotic roof forms such as this A-frame example. Notice the discontinuity in building forms along the street.
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✘
Using too much glass in areas visible from the street is out of character in a residential neighborhood.
G. Solid-to-Void Ratio
Policy:A typical building appeared to be a rectangular solid, with small holes “punched” in the walls for windows and doors. Most buildings had similar amounts of glass, resulting in a relatively uniform solid-to-void ratio. This ratio on a new building, the amount of facade that is devoted to wall surface, as compared to that developed as openings, should be similar to that of historic buildings within the neighborhood.
Guideline:1. Use a ratio of solid-to-void (wall-to-window) that is similar to that found on historic structures in the district.• Large surfaces of glass may be inappropriate. Divide large glass surfaces into smaller panes similar to those seen traditionally.
This new infi ll commercial building uses a traditional solid-to-void (wall-to-window) ratio that is found on commercial structures in the downtown district, which is appropriate.
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50 Design Guidelines
H. Materials
Policy:Building materials of new structures and additions to existing structures should contribute to the visual continuity of the neighborhood. They should appear similar to those seen traditionally to establish a sense of visual continuity.
Guidelines:1. Use building materials that appear similar to those used traditionally in the area.• Horizontal lap siding is appropriate in most residential neighbor-hoods. Brick and stone are also appropriate in most areas.• All wood siding should have a weather-protective fi nish.• The use of highly refl ective materials is discouraged.
2. The use of masonry that appears similar in character to that seen historically is appropriate.• Brick should have a modular dimension similar to that used tradi-tionally. Brick larger than the nominal 2-3/8” x 8” is discouraged.• Stone, similar to that used traditionally, is also appropriate.
3. New materials that are similar in character to traditional materials may be acceptable with appropriate detailing.• Alternative materials should appear similar in scale, proportion, texture and fi nish to those used traditionally.
4. Use building materials that contribute to the traditional sense of scale of the block.• This will reinforce the sense of visual continuity in the district.
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Use building materials that appear similar to those used traditionally in the area.
The use of masonry that appears similar in charac-ter to that seen historically is appropriate.
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The use of hardiplank horizontal lap siding is appropriate in most residential neigh-borhoods outside of the historic district.
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I. Architectural Character
Policy:New construction should distinguish itself from historic structures.
Guidelines:1. The imitation of older historic styles is discouraged for newer structures.• One should not replicate historic styles, because this blurs the distinction between old and new buildings, as well as making it more diffi cult to visually interpret the architectural evolution of the district.
2. Contemporary interpretations of traditional details are encouraged.• Interpretations of historic styles may be considered, if they are subtly distinguishable as being new.• New designs for window moldings and door surrounds, for example, can provide visual interest while helping to convey the fact that the building is new. Contemporary details for porch railings and col-umns are other examples. New soffi t details and dormer designs also could be used to create interest while expressing a new, compatible style.
Contemporary interpretations of traditional details are encouraged.
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52 Design Guidelines
J. Parking
Policy:The visual impact of surface parking should be minimized. On site parking should be subordinate to other uses and the front of the lot should not appear to be a parking area.
Guidelines:1. Minimize the visual impact of surface parking in residential neighborhoods.• A parking area should be located to the rear of a site.• Do not use a front yard for parking. Instead, use a long driveway, or alley access, that leads to parking located behind a building.• Consider using ribbon paving in residential neighborhoods to mini-mize the amount of hard surface paving.
2. Locate a surface lot in the interior of a block whenever possible.• This acknowledges the special function of corner properties, as they are generally more visible than interior lots, serve as landmarks and provide a sense of enclosure to an intersection.
3. Site a surface lot so it will minimize gaps in the continuous building wall of a commercial block.• Where a parking lot shares a site with a building, place the parking at the rear of the site or beside the building.
Where a parking lot abuts a public side-walk, provide a visual buffer.
In residential neighborhoods where alley access is possible the use of parking off the alley is preferred and appropriate. Mark-ing the parking spaces with a different type of material is appropriate as well.
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In commercial or adaptive re-use areas parking is preferred to be set to the rear of the structure.
Before After: option 1 After: option 2
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4. Where a parking lot abuts a public sidewalk, provide a visual buffer.• This may be a landscaped strip or planter. A combination of trees and shrubs can be used to create a landscape buffer.• Consider the use of a wall as screen for the edge of the lot. Materials should be compatible with those of nearby buildings.
K. Buffers
Policy:When site development such as parking, storage and equipment areas create an unavoidable negative visual impact on abutting properties or to the public way, it should be mitigated with landscaping that may buffer or screen it. The landscape design should complement the existing natural character and context of the site.
Note that these guidelines supplement the city standards in Title 18, BMC, that defi ne the minimum amounts of land area to be landscaped and of plant units to be used.
Guidelines:1. Landscape buffers should be provided along edges of parking and service areas.• Provide a landscape buffer at the edge of a parking lot and between parking lots.• In some cases it may be desirable to provide a landscape buffer between a recreation trail and/or open space. These should comple-ment the natural character of the site.• Finally, it may be desirable to provide an evergreen landscape buffer at ground mounted mechanical equipment, service and/or storage areas.
Where a parking lot abuts a public sidewalk, provide a visual buffer.
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54 Design Guidelines
L. Site Lighting
Policy:Standards for outdoor lighting are provided in the Unifi ed Development Ordi-nance. This section addresses some of the qualitative aspects of lighting design that should also be addressed.
Light spill onto adjacent properties and into the night sky should be minimized. The light level at the property line is a key design consideration. This is affected by the number of fi xtures, their mounting height, and the lumens emitted per fi xture. It is also affected by the screening and design of the fi xture.
Guidelines:1. Lighting shall be shielded to prevent any off-site glare.• Light fi xtures should incorporate cut-off shields to direct light downward.• Luminaires (lamps) shall not be visible from adjacent streets or properties.
M. Utilities and Service Areas
Policy:Service areas should be visually unobtrusive and should be integrated with the design of the site and the building.
Guidelines:1. Orient service entrances, waste disposal areas and other similar uses toward service lanes and away from major streets. • Screen service entrances with walls, fences or plantings. • When it will be visible from a public way, a service area screen should be in character with the building and site it serves. • Locate areas for outdoor storage, truck parking, trash collection or compaction loading, or other such uses so as not to be visible from abutting streets.
2. Position service areas to minimize confl icts with other abutting uses. • Minimize noise impacts by locating sources of offensive sounds away from other uses.• Use an alley system to locate service areas, when feasible.
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Minimal shed structures, such as this may be utilized at the alley edge.
Service areas should be visually unob-trusive and should be integrated with the design of the site and the building.
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CHAPTER 3GUIDELINES FOR RESIDENTIAL CHARACTER AREAS
While the porch serves as a transition area from the street to the house, it is also an essential element of the streetscape: It provides human scale to the house; it offers interest to pedestrians; and it is a catalyst for personal interaction.
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56 Design Guidelines
In this Chapter:
A. Hierarchy of Public and Private SpaceB. Building Mass and Scale C. Roof FormD. Secondary StructuresE. Multi-Household F. Fences and Retaining Walls
This chapter discusses the guidelines for residential character areas. It applies to new infi ll projects in the residential neighborhoods in both the Neighborhood Conservation Overlay District and individual His-toric Districts.
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CHAPTER 3.GUIDELINES FOR RESIDENTIAL CHARACTER AREAS
A. Hierarchy of Public and Private Space
Policy:The hierarchy of public and private space is a progression that begins at the street, which is the most public space, proceeds through the front yard, which appears "semi-private," and ends at the front door, which is the "private" space. This sequence enhances the pedestrian environment and contributes to the character of the neighborhood; it should be maintained.
Guidelines:1. Provide a front yard similar in character to its neighbors when possible.• The front yard should be maintained in a traditional manner, with planting material, and not covered with paving or large outdoor decks.
2. Provide a walkway from the street to the building.• A walkway running from the street to the front porch provides unity to the streetscape. Where a walkway has been an element of the hierarchy, this should continue.
3. Orient the front porch to the street.• While the porch serves as a transition area from the street to the house, it is also an essential element of the streetscape: It provides human scale to the house; it offers interest to pedestrians; and it is a catalyst for personal interaction.• This should not be interpreted to exclude side porches.
4. Clearly defi ne the primary entrance by using a front porch. • The porch should be "functional," in that it is used as a means of access to the entry.
The overall set back must be consistent to provide a uniform streetscape.
Clearly defi ne a primary entrance with a front porch.
Provide a walkway from the street to the building.
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58 Design Guidelines
B. Building Mass and Scale
Policy:The mass and scale of a building is also an important design issue in a residential character area. The traditional scale of single household houses dominates the neighborhood, and this similarity of scale also enhances the pedestrian-friendly character of many streets. Similarities in scale among prominent building fea-tures, such as porches and fences, are also important. In many cases, earlier buildings were smaller than current tastes support; nonetheless, a new building should, to the greatest extent possible, maintain this established scale. While new buildings and additions are anticipated that may be larger than many of the earlier structures, this new construction should not be so dramatically greater in scale than the established context that the visual continuity of the neighborhood would be compromised.
Guidelines:1. Construct a new building to be similar in mass and scale to those single household residences seen traditionally.• Traditional features that convey a human scale should also be used. Consider these techniques: - Use building materials that are of traditional dimensions. - Provide a one-story porch that is similar to those seen tradition-ally. 2. On larger structures, step down a building's height toward the street, neighboring structures and the rear of the lot. • When zoning regulations permit, the back side of a building may be taller than the established norm if the change in scale will not be perceived from public ways.
3. On larger structures, subdivide larger masses into smaller “modules” that are similar in size to single household residences seen traditionally. • Other, subordinate modules may be attached to the primary build-ing form. 4. The front wall of a new structure should not exceed two stories in height.• The primary plane of the front should not appear taller than those of typical historic structures in the block. • A new multi-household structure should not overwhelm existing single household structures, in terms of height.
5. A facade should appear similar in dimension to those seen traditionally in the neighborhood.• Typically, a residential building front ranges from 14-30 feet in width. Additional widths were accomplished with a setback or change in building plane.
In order to minimize the perceived scale of a building, step down its height toward the street, neighboring structures and the rear of the lot.
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The drawing on the left shows a structure which does not relate well in mass and scale to the adjacent structure.
On larger structures, subdivide larger masses into smaller “modules” that are similar in size to single household residences seen historically.
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C. Roof Form
Policy:In most neighborhoods, a similarity of roof form also contributes to a sense of visual continuity. In order to maintain this sense of visual continuity, a new building should have basic roof form that is similar to those seen traditionally.
Guideline:1. Use roof forms that are similar to those seen traditionally on the block.• The primary ridge line of a residential structure should not exceed the typical maximum for the block.
D. Secondary Structures
Policy:Secondary structures are traditionally subordinate in scale and character to the primary structure and are typically located to the rear of the lot, they are primar-ily used for parking garages and storage. While structures in the rear generally have little impact on the character of the street they do have an impact on the character of the alley and the neighbors to the rear, this character should be maintained.
Guidelines:1. A new secondary structure should be subordinate in height to those buildings seen traditionally along the street front. • Secondary structures that are no more than one or one-and-one-half stories in height are preferred.
2. Locate secondary buildings to the rear of the lot.• Locating a secondary structure to the side of the primary structure, but set back signifi cantly from the front wall plane is also appropri-ate• A secondary structure should be oriented similar to those seen tra-ditionally along the alley, where they are available.
3. Locate a garage such that its visual impacts will be minimized is encouraged.• If a garage must be accessed from the street, set it back from the front wall plane when feasible.• When a garage must be located on the front wall plane, the percent-age of building front allocated to it should be minimized.
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A facade should appear similar in dimension to those seen traditionally in the neighborhood.
Locate secondary buildings to the rear of the lot.
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This secondary structure is not subordinate to the original structure because the new structure is of equal height.
This secondary structure is only one story and therefore is subordinate to the original structure.
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E. Multi-household
Policy:The underlying goal of the guidelines in this section in regards to multi-house-hold construction is that, to the greatest extent feasible, the buildings should be compatible with the context of the neighborhood. Historic structures associated with the multi-household projects should be retained when feasible.
The guidelines in other sections of this chapter also apply to multi-household buildings.
Guidelines: 1. Retaining an existing single household building that contributes to the established character of the neighborhood in a multi-household project is encouraged. • This will help maintain the traditional scale and character of single household houses as seen from the street.• In particular, an existing structure that is listed as a historic property should be preserved, when feasible.• When proposing a new design for a multi-household structure that must replace an existing building, however, also continue the rhythm that is established by the even spacing of building fronts along the street
2. Minimize the perceive scale of a multi-household building.• In order to minimize the perceived scale of a building, one method is to step down its height toward the street, neighboring structures and the rear of the lot.• In order to break up the perceived mass of a structure, one method is to divide it into "modules" that are similar in size to buildings seen traditionally in the neighborhood.
3. Use traditional features that will convey a human scale. • The ratio of wall-to-window, as seen from the public way, should appear similar to that of traditional single household structures.• Provide a one-story porch, or similar element, which will defi ne a front door or entrance and be oriented to the street.
4. A new multi-household building should be within the range of heights seen traditionally in the neighborhood.• A new multi-household structure should not overwhelm existing single household structures, in terms of height.• Maintaining a consistency of building height will contribute to the visual continuity of the streetscape.• The back side of a building may be taller than the front, and still appear to be in scale, if zoning regulations permit and the change in scale will not be perceived from public ways.
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The proportions of window and door openings should be similar to those used traditionally in the neighborhood.
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5. A primary building face should not exceed the width of a typical single household building in a similar context (see illustrations).• Divide a large facade into subordinate wall planes that have di-mensions similar to those of single household buildings, when feasible.• Develop a large lot with several buildings, rather than one large single structure, when feasible.• When a building is perpendicular to the street, on a lot perpendicu-lar to the street, the typical range of front facade widths is 20 to 40 feet.• When a building is parallel to the street, on a lot perpendicular to the street, the typical range of front facade widths is 30 to 40 feet.• When a building is parallel to the street, on a lot parallel to the street, the typical range of front facade widths is 40 to 75 feet. Note that this is more typical of corner lots.
6. The proportions of window and door openings should be similar to those used traditionally in the neighborhood.• This will help maintain the established ratio of wall-to-window and reinforce the traditional scale of the building.• Large expanses of glass are discouraged.• Divide large glass surfaces into smaller windows to reduce their perceived scale.
7. Brick, stone and painted wood are preferred primary building materials.• A much wider range of secondary and trim materials (including wood, metal, glass and synthetics) occurs.
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This new multi-household household building is not consistent with the traditional width of the surrounding
Traditional materials include brick, stone and wood lap siding.
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The new multi-household building is similar in width to the traditional buildings. This also illustrates the use of dormers to better break up the space.
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8. Orient a primary entrance to the street, when feasible.• This should be similar in scale to traditional single household en-tries.
9. Provide some useful, functional common open space that can be enjoyed by all residents in the development. • Functional and useful open space should be designed to meet the activity needs of residents and should have dimensions and design treatments that accommodate these activities. It should not be left over space, not considered in the design.• The building forms should be arranged to defi ne private yards.• This space should be provided in addition to the more public front yard.
10. Minimize the visual impacts of multi-household garages.• If enclosed parking is provided, consider locating it in a detached garage on the alley, when feasible. • In a larger structure that includes parking, consider breaking up the mass of the building and its roof forms to minimize its visual impact.• Locating enclosed parking in the front facade of a multi-household building is inappropriate. Doing so may increase the perceived mass and scale of the structure as a whole.
11. Design a surface lot with landscaping.• In a case where more than three parking spaces must be accommo-dated in the rear yard off the alley, landscaping should be provided between every second car to provide visual relief and to maintain pedestrian access to the alley from rear yards.• Where more than one parking space is located parallel to the alley, a landscape buffer should be provided between the alley and the parking space.• Also, minimize the amount of area that is paved for parking and consider using a variety of paving materials to distinguish parking spaces.
This multi-household garage is well integrated into the surrounding garage structures. Notice the space being broken up into many units.
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F. Fences and Retaining Walls
Policy:Traditionally front yard fences were relatively low in height and had a “transpar-ent” character that allowed views into yards, providing interest to pedestrians. Solid plank wood fences were used occasionally along alley edges, but also were relatively low in height. A new or replacement fence should be similar in character with those used traditionally in the neighborhood. In addition, fences should relate in character to the principal structures on the lot.
In some areas retaining walls are also found. They typically align along the edges of sidewalks, and help to establish a sense of visual continuity and should be maintained.
Guidelines:1. A new fence should be in character with those seen traditionally.• A fence that defi nes the front yard is usually low to the ground and “transparent” in nature.• Chain link and solid “stockade “ fences are discouraged in front yards.• Painted wood picket, simple wire and ‘wrought iron” fences are appropriate materials.
2. A new retaining wall should be in character with those seen traditionally.• A retaining wall that defi nes the sidewalk edge or is used in the front yard should not exceed 36 inches. • Use similar materials that are similar to those used traditionally, such as cut rock and stone. In some cases concrete may be an ap-propriate material.
Traditionally front yard fences were relatively low in height and had a “transparent” character that allowed views into yards, providing interest to pedestrians as shown in these early sketches.
The fencing plans show how a side or rear yard fence can appear more “transparent”. Plan A shows the fence boards slanted at a 45 degree angle. Plan B shows the fence boards altering between front and back plane. Both plans allow for views into yard.
Plan A
Plan BPlan B
Post
Post
Fence boards
Fence boards
View throughView through
View throughView through
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The fence in the image above is in character with those seen traditionally.
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