HomeMy WebLinkAboutStructural Engineer's Report 03.28.20186SGM
MEMORANDUM
TO: Jaime Araujo
FROM: John Partch, PE
DATE: March 28, 2018
RECEIVED
APR 0 2 2018
GARFIELD COUNTY
COMMUNITY DEVELOPMENT
RE: 3911 CR 100 —Structural Repairs and Improvements
This list of required structural improvements is an addendum to our previous
report on the preliminary structural analysis of the existing addition. Please refer
to the previous report for the analysis and reasoning of the required
improvements. Our recommended repairs and improvements are based on a
review of the plans and dimensions provided, construction photos provided to us,
and a onsite observation when most of the construction was finished and
structural elements were largely concealed by finish materials.
Specific items that need to be verified or remedied to bring the addition into
compliance with the structural requirements of the Garfield County building
department standards and the 2015 International Residential Code are:
1. Add a 2-2x12 header beam for the roof rafters in line with the hallway
walls across the living room.
2. Add 2-2x8 headers over the door openings in the interior hallway wall.
3. Attach the 2x12 ledger board supporting the floor framing to the existing
concrete foundation wall with '/Z" diameter expansion or epoxy anchor
bolts at 8" o.c.
4. Add 6x6 posts and a minimum of 24" diameter x 8" thick concrete footings
at the mid span of the 3-2x12 beams below the hallway/bathroom wall and
the south side of the building to provide additional foundation support.
Footings should be a minimum of 36 inches below grade for frost
protection.
5. Have a geotechnical engineer verify that the existing post embedment and
support is sufficient for foundation support of 6000 pounds per post.
118 W. 6th St, Ste 200 Glenwood Springs, CO 81601 Phone: 970-945-1004 Fax: 970-945-5948
Construction photos that we reviewed and sketches of the proposed repairs and
improvements are attached. All improvements shall be done in accordance with
the 2015 International Residential Code and the following general structural
notes:
Reinforced Concrete:
1. Cast in place concrete shall be made with type I/I1 or type V sulfate -resistant cement with
fly ash with a minimum compressive strength of 2500 psi. Admixtures containing chloride
salts shall not be used.
2. Hot and cold weather concreting procedures shall conform to the recommendations in the
ACI Manual of Concrete Practice.
Concrete and Masonry Anchors:
. Expansion Bolts are to be "Kwik Bolt TZ" manufactured by Hilti, Inc. Install in accordance
with ICC Report ESR -1917 or approved update, including standard embedment depths,
unless noted otherwise. Proposed substitutions shall have equal or greater capacity and
shall be submitted to the engineer for review with product data and code approval
reports.
2. Epoxy Grouted Anchors and Reinforcing Steel in Concrete are to be HIT -Z anchor rods
or HAS threaded rods installed using "HY-200 Adhesive Anchoring System"
manufactured by Hilti, Inc. Install in accordance with ICC Report ESR -3187 or approved
update, including standard embedment depths, unless noted otherwise. Proposed
substitutions shall have equal or greater capacity and shall be submitted to the engineer
for review with product data and code approval reports.
Wood Framing:
1. Wood framing shall be kiln dried lumber graded and marked in accordance with the
following minimum standards unless noted otherwise:
Studs, plates, and miscellaneous framing:
Douglas Fir Larch No.2
Dimensional joists, beams, and headers (2x, 3x, & 4x members):
Douglas Fir Larch No. 2
Heavy Timber Beams and Columns (6x and larger members): Spruce -
Pine -Fir or Douglas Fir Larch No. 1
Exposed to weather, moisture, or in direct contact with concrete:
Pressure Treated Southern Pine No. 2
2. All wood framing details not shown otherwise shall be constructed equal to or better than
the minimum standards of the 2015 IRC.
3. Minimum nailing requirements: Unless otherwise noted, minimum nailing shall be in
accordance with the Fastening Schedules and Details of the 2015 IRC.
4. Individual members of built-up posts and beams shall each be attached with 16d spikes at
12" o.c. staggered.
5. Provide solid blocking for wood columns and multiple studs through floors to supports
below.
118 W. 6'" St, Ste 200 Glenwood Springs, CO 81601 Phone: 970-945-1004 Fax: 970-945-5948
6. All steel fasteners, hangers, and plates in contact with pressure treated wood shall be hot
dipped galvanized or have other corrosion protection.
7. Hanger -type connections shall be made with Simpson Strong -Tie connectors and
manufacturer -supplied fasteners. Wood columns shall be extended to foundations, or
stud blocking the same size as the column installed tight in the joist space under the
column.
8. Wood Fasteners:
Nail sizes specified on the drawings are based on the following specifications:
Drawing ID Nail Name Nail Diameter Nail Length
"8d Box" 8d Box 0.113" 2 'A"
"8d" 8d Common 0.131" 21/4"
"10d Box" 10d Box 0.128" 3"
"10d" 10d Common 0.148" 3"
"16d" 16d Sinker 0.148" 3'/e"
Alternative nails proposed by the contractor shall be submitted with specifications to the
structural engineer prior to construction for review and approval.
This report is based on our site observations, research of available records, and
experience with structures of this type in this area. Our observations were limited
by the presence of backfill, finish materials, and physical constraints. Unseen
defects or conditions may exist that could affect the structural integrity of the
structures observed. The observations, interpretations and conclusions herein
have been conducted to the standard of care ordinarily practiced by other
engineers in this area at this time. No warranty is made, express or implied.
1 18 W. 6'h St, Ste 200 Glenwood Springs, CO 81601 Phone: 970-945-1004 Fax: 970-945-5948
Existing
LEGEND:
Existing framing and notation in black
Proposed framing and notation in red.
A
N
C)
Kitchen
8'
Hallwa
14'-5 1 /2"
Bathroom
Add (2)-2x12 header
beam
Living
Room
8'
Lie
Roof Framing Plan
N.T.S.
A.11_11"
Bedroom
12'
Bedr
—12'
• TS -1 NNNNNNNNNNNNNN'
Add 1/2" expansion ;
or epoxy anchor bolts
at 8" o.c. to existing
2x12 ledger board ;
Existing
Kitchen
8'
LEGEND:
Existing framing and notation in black
Proposed framing and notation in red.
Add I joist blocking in 3 joist
spaces below each living
room header support
S 1 1 1 1 1 1 1 1 S. 1 1 1 S 1 1 1 1 1 1 1 1 I
Living
Room
8'-
, 1
CONTINUOUS (3)-2x12
C
%J
T—
Existing (3)-2x12
14'-5 1/2"
I0
o0
Bathroo
Add new 6x6 posts and
minimum of 24"
diameter x8" concrete
00 ing
Existing (3)-2x
Bedroom
Existing 8x8 POSTS
at 8' o.c.+-, TYP.
12°
`ter r
Floor Framing Plan
N.T.S.
Be(
:-12'
� ■ Y
12
t.rr
a
•
)Om
4.1
CV
r
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