HomeMy WebLinkAboutL Street Structural Report
L STREET, TURNER/GRIFFEN, AND HENDERSON
STRUCTURAL BUILDING INSPECTION
Story Mill Rd. and Griffen Dr.
Bozeman, MT
Ty Monks, Managing Principal, Montana P.E.#15860
August 31, 2012
NM No. 12044.01
Prepared for:
The Trust for Public Land
111 South Grand Ave., Suite 203
Bozeman, MT 59715
Prepared by:
Nishkian Monks, PLLC.
108 West Babcock St.
Bozeman, MT 59715
406.582.9901 tel | 406.582.9992 fax
TABLE OF CONTENTS
Introduction .........................................................................................................................1
Limitations ..........................................................................................................................1
Background ......................................................................................................................... 1
Observations, Analysis, and Opinions ................................................................................1
Building “A”, L Street Parcel, Small Residence ....................................................2
Building “B”, L Street Parcel, Multi-unit Storage Facility .....................................2
Building “C”, L Street Parcel, Shop Building ........................................................3
Building “D”, L Street Parcel, Meat Processing/Slaughter House .........................3
Building “E”, Turner/Griffen Parcel, Storage Facility ...........................................4
Building “F”, Turner/Griffen Parcel, Accessory Dwelling ....................................4
Building “G”, Turner/Griffen Parcel, Residence ....................................................4
Building “H”, Turner/Griffen Parcel, Storage Facility ...........................................5
Building “I”, Turner/Griffen Parcel, Storage Barn / Accessory Dwelling .............5
Building “J”, Henderson Parcel, Residence ............................................................6
Building “K”, Henderson Parcel, Storage Barn ......................................................6
Conclusion .......................................................................................................................... 6
Evaluation Purpose .............................................................................................................7
Appendix Exhibits ..............................................................................................................8
Exhibit A – Story Mill Property Map
Exhibit B – Story Mill Parcel Building Key Plan
Exhibit C – Figures
108 West Babcock, Bozeman, MT. 59715
www.nishkian.com
August 31, 20012
Mr. Alex Diekmann
The Trust for Public Land
111 South Grand Ave., Suite 203
Bozeman, MT 59715
Re: Building Inspections of Structures on L Street Parcel, Turner/Griffen Parcel, and
Henderson Parcel; Story Mill Property, Bozeman, Montana.
Finalice
Introduction
As requested, our office conducted a structural review/inspection of the existing buildings
currently occupying the L Street Parcel, Turner/Griffen Parcel, and Henderson Parcel within the
Story Mill Historic District, located in the northeast corner of Bozeman, Montana. The scope of
our inspection services included four structures on the L Street Parcel, 5 structures on the
Turner/Griffen Parcel, and two structures on the Henderson Parcel (Appendix A, Story Mill
Property aerial map). This report presents our findings and recommendations regarding structural
damages on the subject buildings, as well as a short discussion on possible adaptive re-use
suitable for the structures.
Limitations
Our professional services have been performed using that degree of care and skill ordinarily
exercised, under similar circumstances, by reputable engineers practicing in the structural field in
this or similar localities at this time. No other warranty, expressed or implied, is made as to the
professional advice included in this report. This report has been prepared for the Trust for Public
Land, and is intended to be used solely in its evaluation of the subject properties. The report has
not been prepared for use by other parties and may not contain sufficient information for purposes
of other parties or other uses.
Background
The scope of our inspection services included eleven structures on three separate parcels. The
structures are separate buildings, varying in height and construction type. The identified
structures in this report include commercial buildings, storage barns, and single-family residential
buildings. This report presents our findings and recommendations regarding structural damages
on the subject buildings, as well as a short discussion on possible adaptive re-use suitable for the
structures.
Observations, Analysis, and Opinions
During the first two weeks of June 2012, Ty Monks and Tyler Hessler from our office conducted
a site visit to the structures on the L Street Parcel, Turner/Griffin Parcel, and Henderson Parcel to
inspect the buildings. The buildings were un-occupied, boarded up, and mostly without power.
Hence, the visibility was limited to the illumination available through flashlights.
Mr. Alex Diekmann
Re: Building Inspection
Mill Parcel, Bozeman
July 23, 2012
2
Building “A”, L Street Parcel: A small residence, single story with covered entrance porch. The
overall footprint of the building is approximately 33 feet by 22 feet.
The building structural systems are as follows:
1. Foundation – Perimeter concrete strip footing with concrete stem wall allowing for
standard crawl space access;
2. Walls – Standard light-framed wood stud (2x4’s @ 16”o.c.) construction;
3. Floors – 2 inch x 10 inch joists at 24 inches on center;
4. Roof – 2 inch x 6 inch rafters at 24 inches on center with plywood gusset rafter
connection along ridge line.
The small residence appears to be of sub-standard construction. The exterior wall joist size does
not allow for the installation of adequate insulation thicknesses. Although the foundation system
does not indicate any differential settlement, the floor diaphragm dips up to 1 inch in the corners
of the rooms. The roof rafters have been connected with plywood gussets to create trusses that are
questionable, especially considering the spans and spacing of its members. The front façade has
partial height stone veneer supported by steel angles. The veneer shows no cracking and is in
relative good condition.
Giving it’s age and construction deficiencies, the building would need to be substantially
renovated - both, structurally and architecturally – in order to re-occupied as a residence. Minor
renovation might suffice if the building serves as a temporary shelter during the summer month.
Building “B”, L Street Parcel: A multi-unit storage facility with garage door entrances to each
unit. The overall footprint of the building is approximately 100 feet by 29 feet.
The building structural systems are as follows:
5. Foundation – Perimeter concrete strip footing and interior spread footings;
6. Walls – Exterior walls are unreinforced concrete masonry units at the bottom 5 foot 3
inches and 2x4 stud framing on the top. Interior partition walls are standard light-framed
wood stud construction;
7. Floors – Approximately 2/3 of the building has a concrete slab-on-grade, while the rest of
the units have gravel flooring.
8. Roof – Flat roof with 10” deep metal rafters spanning between heavy gage multi joist
steel beams supported on 4 inch square tube steel columns at a 14 foot by 16 foot grid.
Generally, this utilitarian building was constructed per commonly used framing standards for
storage facilities of similar size. Besides some differential foundation settlement below the
exterior wall at the south/east rear corner of the building, the structure appears to be in excellent
condition. The settlement occurs below a non-bearing wall and hence does not affect the overall
stability of the building. However, we recommend that the settlement is being further
investigated by a geotechnical engineer to determine if the close proximity of the building to the
creek in the back of the building will not cause further foundation settlement in the future.
Building “C”, L Street Parcel: A two-story shop building on the west side of the creek dividing
the property. The overall footprint of the building is approximately 75 feet by 50 feet.
The building structural systems are as follows:
1. Foundation – Perimeter concrete strip footing and interior spread footings;
Mr. Alex Diekmann
Re: Building Inspection
Mill Parcel, Bozeman
July 23, 2012
3
2. Walls - Constructed of concrete masonry units with undetermined reinforcement layout.
The building has an open floor plan without any interior walls;
3. Floors – The ground floor has a concrete slab on grade, and upper level has an elevated
concrete one-way slab.
4. Roof - Flat roof with wood rafters spanning between heavy timber beams supported by 8
inch square heavy timber wood posts.
The shop building appears to have not been in use for any years. The lower level entrances to the
building are heavily overgrown by vegetation and are difficult to open. There is an exterior wood
framed stair leading to the upper level entrance door. The stair is on its verge to collapse and
needs immediate replacement. The concrete floor slab at the upper level has cracks along the
supporting beam lines. The types of floor cracks, however, are common in old structures due to
concrete creep and/or foundation settlement. On the other hand, more concerning are the
conditions of some of the concrete support columns. We’ve noticed spalling of concrete at the
base of the columns, exposing reinforcement and hence compromising the stability of those
columns.
According to our visual review of the building, a structural rehabilitation must involve retrofitting
the basement columns and foundations. The upper level, besides being littered with debris, is
structurally salvageable.
Building “D”, L Street Parcel: A meat processing/slaughter house with office spaces. The type
of construction is reflective of the mid1900’s era. The overall footprint of the building is
approximately 50 feet by 100 feet.
The building structural systems are as follows:
1. Foundation – Perimeter and interior concrete strip footing with concrete stem walls
elevating the building above grade;
2. Walls – Exterior walls are a combination of unreinforced multi-wythe brick masonry,
concrete masonry block, and concrete. The interior walls are a combination of concrete
and standard light-framed wood stud construction;
3. Floors – The ground floor is a concrete slab-on-grade at an elevated level compared to
the exterior grade (approximately 3 foot). Interior open loft spaces and office partitions
utilize wood diaphragms;
4. Roof – Flat roof with wood rafters spanning between heavy timber beams supported by
interior walls or wood posts.
Due to the combination of different construction methods and materials, it appears that this
building has undergone several renovations/alterations with periodic additions being made to
accommodate changing requirements for the building. Different settlement has occurred between
the original structure and the additions, causing wall and foundation cracks. Furthermore,
concrete columns in the partial basement on the east side of the building are heavily compromised
by water damage. This part of the building needs to be entered with extreme caution, and shoring
efforts need to proceed and type of reconstruction or remodeling in this part of the building.
Sloping floors on the main level, at the north end of the building, were purposely installed to
provide drainage during cleanup. Due to the incompatibility of the building additions to the
original building, we would anticipate substantial structural mitigation work needs to occur.
Mr. Alex Diekmann
Re: Building Inspection
Mill Parcel, Bozeman
July 23, 2012
4
Building “E”, Turner/Griffen Parcel: A storage facility (pole barn) with garage door entrance
and storage sheds on two sides of the building. The overall footprint of the building is
approximately 62 feet by 40 feet.
The building structural systems are as follows:
1. Foundation – Assumed turned down edge concrete slab perimeter footing;
2. Walls – Solid wood posts and multi-stud posts at 6 to 8 foot on center with horizontal 2x
planks at 2 foot on center and sheathed with metal siding;
3. Floors – Concrete slab-on-grade;
4. Roof – Pre-engineered gang nailed wood trusses at 4 foot on center with 2x sleepers and
metal roofing.
The above described storage facility is in pristine condition with only minor dents in the exterior
siding. No structural deficiencies were detected and the facility is ready to be used per its
intended purpose.
Building “F”, Turner/Griffen Parcel: A single-story, barn style, accessory dwelling unit with
attic loft bedroom space. The overall footprint of the building is approximately 20 feet by 30
feet.
The building structural systems are as follows:
1. Foundation – Concrete strip footing at the perimeter;
2. Walls – Standard wood stud framing with plastered exterior finish;
3. Floors – Assumed concrete slab-on-grade;
4. Roof – Stick framed roof with 2x6 rafters at 2 foot on center and metal roofing.
The building is structurally sound, though we were unable to physically verify building member
connections due to the applied finishes. The interior stairs and spaces (ceiling heights) do not
appear to be code compliant and most likely would need to be reconfigured in order re-occupy
this dwelling.
Building “G”, Turner/Griffen Parcel: A single-story residence with attic living spaces and large
backyard deck. The overall footprint of the building is approximately 40 feet by 30 feet.
The building structural systems are as follows:
1. Foundation – Perimeter concrete strip footing with concrete stem wall allowing for
standard crawl space access;
2. Walls – Standard light-framed wood stud (assumed 2x6’s @ 16”o.c.) construction with
plastered exterior finish;
3. Floors – Assumed plywood over wood joists;
4. Roof – Pre-engineered gang-nail trusses and conventional stick framing with asphalt
shingles.
Since this building was completely secured and inaccessible, we were unable to inspect the
interior spaces. However, the exterior of the building appeared to be in good structural condition
with no visible cracking on any of the walls or foundations. The siding and fascia boards on the
western façade of the building were extensively damaged by strong hail, possible allowing
rainwater to penetrate and affect the framing.
Mr. Alex Diekmann
Re: Building Inspection
Mill Parcel, Bozeman
July 23, 2012
5
Building “H”, Turner/Griffen Parcel: A storage facility (pole barn) with garage door entrance
and covered side deck. The overall footprint of the building is approximately 40 feet by 30 feet.
The building structural systems are as follows:
1. Foundation – Assumed turned down edge concrete slab perimeter footing;
2. Walls – Preservative treated wood posts 10 foot on center with horizontal 2x planks at 2
foot on center and sheathed with metal siding;
3. Floors – Concrete slab-on-grade;
4. Roof – Plywood gusset plated wood trusses at 10 foot on center with 2x6 rafters at 2 foot
on center and metal roofing.
The above described storage facility is in good condition. No structural deficiencies were detected
and the facility is ready to be used per its intended purpose.
Building “I”, Turner/Griffen Parcel: A storage barn connected to a multi-unit accessory
dwelling. The overall footprint of the building is approximately 120 feet by 25 feet.
The building structural systems are as follows:
1. Foundation – Assumed turned down edge concrete slab perimeter footing at storage barn
and strip footing at dwelling units;
2. Walls – Standard light-framed wood stud construction;
3. Floors – Slab-on-grade at storage barn and lower level dwelling unit, wood joist floor at
elevated dwelling units;
4. Roof – Assumed stick framed pitched roof with metal roofing at the storage barn and
asphalt shingles at the dwelling units.
The dwelling units are structurally unsafe due to extensive dry rot, sub-standard construction, and
under sized support members. It is our opinion that the dwelling units are uninhabitable and any
repair efforts would be cost prohibitive. The storage barn may be saved and used per its intended
purpose after only minor cleanup efforts.
Building “J”, Henderson Parcel: A single-family residence with partial utility basement below
kitchen area. The overall footprint of the building is approximately 30 feet by 56 feet.
The building structural systems are as follows:
1. Foundation – Perimeter concrete strip footing with concrete stem wall allowing for
standard crawl space access and concrete retaining walls at the utility basement;
2. Walls – Standard light-framed wood stud (2x6’s @ 16”o.c.) construction;
3. Floors – 2 inch x 8 inch joists at 16 inches on center;
4. Roof – 2 inch x 4 inch rafters at 24 inches on center.
The residence appears to be of sub-standard construction. The vinyl exterior west facing siding
was extensively damaged by strong hail, possible allowing rainwater to penetrate and affect the
framing. The entrance hallway south of the kitchen slopes ½ inch per foot from side to side. The
Mr. Alex Diekmann
Re: Building Inspection
Mill Parcel, Bozeman
July 23, 2012
6
sloping of the hallway is caused by a rotation of the exterior wall footing supporting the hallway
framing. This rotation is most likely due to unstable subgrade and needs to be addressed as soon
as possible to control further damage to the building.
Similar to our assessment of building “A”, considering the construction deficiencies, the building
would need to be substantially renovated - both, structurally and architecturally – in order to be
re-occupied as a residence.
Building “K”, Henderson Parcel: A pole barn with a large barn door opening and clearstory
openings above a center aisle space. The overall footprint of the building is approximately 60 feet
by 110 feet.
The building structural systems are as follows:
1. Foundation – Rubble;
2. Walls – Preservative treated wood posts 10 to 12 foot on center with horizontal 2x planks
at 2 foot on center and sheathed with metal siding;
3. Floors – Mostly gravel with the exception of a 22 foot by 24 foot concrete slab-on-grade
at the north/east corner of the barn;
4. Roof – Bolted wood trusses at 12 foot on center with 2x6 rafters at 2 foot on center and
metal roofing.
The pole barn shows no apparent structural concerns besides deflections of the roof trusses. The
deflections in the trusses are most likely caused by slippage of the bottom chord’s central splice.
It appears that the deflections have reach equilibrium and no further deflections can be expected.
It is our opinion that the barn is structurally safe and ready to be used per its intended purpose.
Conclusion
Generally, the storage facilities and barn structures on the L Street, Turner/Griffen, and
Henderson Parcel are constructed according to industry standards. Since these types of buildings
are only temporarily occupied and mostly are designed to hold machinery or general storage
items, the structures pose reduced risks to human lives. On the other hand, the residential
buildings need to conform to stricter building code guidelines and provide certain comforts.
Hence, the majority of the residential units did not fair as well and are probably not worth saving,
unless ones expectations for these building are kept low or substantial improvements are
budgetarily acceptable. The two heavy commercial buildings on the L Street Parcel, if
historically significant, are structurally salvageable with moderate investments as long as no
adaptive re-use changes the structural loading conditions.
Evaluation Purpose
The purpose of this report is to identify any structural damages to the subject properties. The
report is not designed to evaluate the building for probable damage to the structure in the event of
future strong ground shaking or other natural disasters. Hence, we did not base our findings on
the type and quality of construction; configuration, age, and condition of the building; and its
seismic-resistant system.
This inspection was of a visual nature only. Every condition or potential structural condition may
not have been noted. Observations made and probable conclusions reached were based on visual
examination and evidence without the benefit of direct observation of some structural elements.
In some cases, exact determination of workmanship and structural integrity cannot be made
without destruction of interior or exterior finishes.
Mr. Alex Diekmann
Re: Building Inspection
Mill Parcel, Bozeman
July 23, 2012
7
Thank you very much for the opportunity to be of service. We trust the foregoing is adequate for
your needs, but should you have additional questions please contact the undersigned.
Very truly yours,
NISHKIAN MONKS
Tilden Monks, PE
Managing Principal
APPENDIX EXHIBITS
Appendix
“C”:
Figures
Fig.
2:
Crawl
space
entrance
at
the
back
of
the
building.
Fig.
1:
Front
view
of
L
Street
Parcel
Residence.
Fig.
3:
Concrete
masonry
block
crawl
space
stem
walls.
No
attachment
of
floor
framing
to
foundation
wall.
Fig.
4:
Stacked
concrete
blocks
as
beam
support
with
no
connection
hardware.
Fig.
5:
Exterior
view
of
brick
veneer.
Fig.
6:
Multi-‐unit
storage
facility
on
L
Street
Parcel.
Fig.
7:
Multi-‐stub
steel
beam
connected
to
tube
steel
support
column.
Fig.
8:
Steel
deck
roofing
of
storage
facility.
Fig.
9:
Foundation
wall
crack
at
south/west
corner
of
storage
facility.
Fig.
10:
Foundation
wall
crack
at
south/west
corner
of
storage
facility.
Fig.
11:Exterior
view
of
L
Street
Parcel
shop
building.
Fig.
12:
Heavy
timber
beams
supported
on
timber
columns
at
the
upper
level
of
the
shop
building.
Fig.
13:
Interior
of
upper
level
of
the
shop
building.
Fig.
14:
Concrete
slab
cracks
along
column
lines.
Fig.
15:
Base
of
concrete
column
supporting
the
upper
level
of
the
shop
building.
Fig.
16:
Roof
trussed
area,
attic
space,
at
the
meat
processing/slaughter
house.
Fig.
17:
Exterior
view
indicating
additions
to
the
building.
Fig.
18:
Wall
cracks
between
original
structure
and
addition.
Fig.
19:
Wall
cracks
between
original
structure
and
addition.
Fig.
20:
Wall
cracks
between
original
structure
and
addition.
Fig.
21:
Wall
cracks
between
original
structure
and
addition.
Fig.
22:
Basement
concrete
column
with
exposed
reinforcement
at
base.
Fig.
23:
Basement
concrete
column
with
exposed
reinforcement
at
base.
Fig.
24:
Sloped
concrete
floor
for
drainage
during
cleanup.
Fig.
25:
Exterior
view
of
storage
barn
at
Turner/Griffen
Parcel.
Fig.
26:
Exterior
view
of
storage
barn
at
Turner/Griffen
Parcel.
Fig.
27:
Denting
of
exterior
siding.
Fig.
28:
Exterior
view
of
accessory
dwelling.
Fig.
29:
Stairs
leading
up
to
loft
sleeping
area.
Fig.
30:
Residence
on
Turner/Griffen
Parcel.
Fig.
31:
Pack
deck
entrance
of
residence.
Fig.
32:
Exterior
view
with
dormers
indicates
attic
living
spaces.
Fig.
33:
Hail
damage
to
roof
fascia.
Fig.
34:
Hail
damage
to
plastered
wall.
Fig.
35:
Hail
damage
to
trim
board.
Fig.
36:
Hail
damage
to
gutters.
Fig.
37:
Exterior
view
of
second
storage
barn
on
Turner/Griffen
Parcel.
Fig.
38:
Interior
view
of
second
storage
barn
on
Turner/Griffen
Parcel.
Fig.
39:
Interior
view
of
second
storage
barn
on
Turner/Griffen
Parcel.
Fig.
40:
Exterior
view
of
storage
barn
connected
to
multi-‐unit
accessory
dwelling.
Fig.
41:
Post
collapse
at
partial
basement.
Fig.
42:
Roof
shingles
in
disrepair.
Fig.
44:
Interior
view
of
storage
barn.
Fig.
43:
View
of
front
of
dwelling
unit.
Fig.
45:
Interior
view
of
storage
barn.
Fig.
46:
Exterior
view
of
residence
on
Henderson
Parcel.
Fig.
47:
Utility
basement.
Fig.
48:
Interior
view
of
roof
framing
–
attic
space.
Fig.
49:
Hail
damage
to
west
façade
of
residence.
Fig.
50:
Rotated
foundation
wall
at
exterior
of
hallway.
Fig.
52:
Interior
view
of
pole
barn
on
Henderson
Parcel.
Fig.
51:
Exterior
view
of
pole
barn
on
Henderson
Parcel.
Fig.
53:
Support
post
on
rubble
foundation.
Fig.
54:
Wood
trusses
with
deflection
of
bottom
chord.