HomeMy WebLinkAboutEngineer Report 08.23.2021Studio M Engineers" LLC
Structural Engineering Consultants
Innovatíon By Per ception
www.mbengineering.elementfx.com
studíom.engineer@gmaíl.com
August 23,2021
Rle 28271 Highway 6 and 24, Auto Glass and Auto Body Pro, Roof Hood Vent
To Whom it May Concern,
At the request of Mrs.Maricela Ramirez my office was asked to review plans for the
installation of a auto paint ventilation hood in a shop located at2827l Highway 6 and24
just East of Rifle. The review would involve an inspection of the existing facility, an
inspection of the roof structure, and a review of how the hood ventilation system
installation process, specifically as it related to modification of the existing roof structure.
pROJECT DESCRIPTION: 28271 Highway 6 and24 is a commercial building located
on the north side of Highway 6. The shop has an office, bathroom and storage space on
the west, a storage loft over the office, and an auto body work bay on the east half of the
building. The building is approximately 50 foot in the east-west direction and 40 foot in
the north south direction.
OBSERVATIONS: The roof structure is a prefabricated wood truss system known as a
parallel chord truss. The truss depth is 36 inches. The roof slope is approximately % inch
per foot, with the high end being towards the front of the building. The truss span is
around 38'-3"(inside of support to inside of support). The vent system consists of an
intake hood and an exhaust stack. The hood unit partially bears on the roof. The hood
measured 69 inches x I I I inches and weighed260lbs based on a scale measurement
taken by the owner.
TRADE
From
111 East 3'd st.#2O2 a Rífle Colorado a 8165o .97o366-869o.
The original hood unit roof penetration for both the intake and ventilation is 30 inch x 30
inch. In an effort to not cause extensive remodeling repair and redo to the roof structure
trusses, I advised that an adapter be built into the system that allowed the hood system to
pass betwcen thc prcfabricated wood roof trusses (24 inch on center spacing). With this
method, the only structural modification that would be required would be 2 openings in
the roof diaphgram (i.e. wood roof sheathing), one for the intake and one for the
ventilation. Based on a layout provided by the owner, the holes would be22 inch wide
and 38 inchcs long. Hole locations are shown on the attached diagram. Dimensions were
provided my office by the owners representative.
CONCLUSIONS AND RECOMMENDATIONS:
Ventilation System Loading: The exhaust stack of the system is self contained, meaning
it does not depend upon the roof for supporl. The stack self weight travels to the slab on
grade in the shop space below. The stack does extend above the roof, where it is fastened
with guide wires to provide lateral stability during design load wind or seismic events. 4
cables would need to be installed to give the unit lateral stability. Based upon the unit
profile, the cables and clamps would need to have a load rating of at least 250 lbs (service
level load). A recommended detail for cable attachment is provided in this report.
The intake system self weight is just under 5 pounds per square foot and is considered as
negligible in terms of additional load on the existing unmodified wood roof system. The
width to height to length ratio provides an overturning ability that exceeds the code
requirement safety factor of 1.5, just by the nature of the unit gcomctry. No guidc cablcs
would be required.
Any type of screw down attachment or roof membrane penetration should be reviewed
and/or installed by a qualified roofing and waterproofing specialist in an effort to prevent
leaks, water intrusion, or voiding of roofing warranties.
IÍ East 3'd st. #2O2 . Rifle Colorado o 8t65o .97o366-869o.
Roof Diaphragm Penetrations: The two roof top penetrations make up a combined area
ofjust under 12 square foot. By contrast, the roofsurface is 2000 square foot. The
penetrations make up just 0.60/o of the roof and are considered as negligible based on their
square foot size and location. The locations relative to the building plan profile are
identified in the attached sketch for the reader's reference. This is an area of lower shear
stresses in the roof diaphragm (i.e. towards the building center)
Roof Truss Capacity: The roof truss depth was checked with the prefabricated roof truss
company Overholt, based out of Delta Colorado. The attached truss shop drawing
indicates that this depth of wood truss is completely capable of making the 40 foot span
under the design loads of Garfield County (40 psf roof snow load).
Loads used in Design: The loads and code used in design analysis are presented in the
attachment page lA. These codes and values are taken from the Garfield County Climatic
Design Criteria and loading requirements.
SUMMARY
This concludes my report.
Sincerely,
Wrc*ft
Michael J. Baca, P.8., NCEES
Principle Structural Engineer
Enclosures: hole locations, cable tie down detail, design load parameters
cc: Maricela Ramirez, autoglasasndautobodypro@hotmail.com
AL
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I 111 East 3rd st. #202 a Rifle Colorado a 8165o .97o-366-869o '
28271HIGHWAY 6
AND 24
AUTO GLASS + AUTO
BODY PRO
SHEET:
1 .A
STUDIO M TNGINETRS, LLC
STRUCTU RAL CON 5 U LTANTS DRATTED BY: MJB
DESIGNED BY: MJD
DATE: B.3O.2O2l
SCALI: AS SllOWNr I i rAST 3RD 3r. #?O2
COLORADO B I 650
?7O 3ç,G ñç,3O
ONAL
LI
aa
J
7
0
18',-?',
b_tlo
b_tlo
HIøHWAY 6 AND 24
?=NETRATICN PI-AN
PI.AN NORTH
1/8" = 1'-O"
28271 HIGHWAY 6
AND 24
AUTO GLASS + AUTO
BODY PRO
2.4
SHEET:STUDIO M ENGINTTRS, LLC
STRU CTU RAL CO N5 U LTANTg DRAFTED BY: MJB
DESIGNED BY: MJB
DATE; E.3O.2O2l
SCALE: AS S|1OWNr r EA9T 3RD 5f. #202
coLoRADO 81650
970-3GC-A690
t
0
/o¡v¡,u
t
la
J
7
Oal
ovES5lzED
?141F- WAgHERROOF
9HEATHINø 5/8',DlA.
EYE BOLT 4.16D FACE
NAILg, IYIN
2X10 BLOCK'O
INgTALLED
TO UNDERãIDE OF
ROOF gHEATHIN€36'DEEP
?qEFA.B
wooD
?ooF
TRU99
(EXreïNø)
L. If2"= L'-A"
NOTE9
1. BOLT CENTERg IN TRU99 BAY
2, WÑER?AOOF ALL ROOFINø PENETI?ATIONg
3. DO NOT NAIL INTO ØLOC<'E TH?OUOH ROOF gHEATHINø
4. CAäLE gYgTEYt LOAD I?ATIN o = 25OLB (gERVlcE) FrlN.
28271 HIGHWAY 6
AND 24
AUTO GLASS + AUTO
BODY PRO
3.4
SHEET:STUDIO M ENGINEERS. LLC
STRUCTU RAL CONSU LTANTS DRAFTFD RY; M.lR
DE9IGNED BY; MJB
DATE: E.3O.2O2l
SCALE: A3 SllOWNr I EA5T 3RD 3Í. #202
COLORADO EIC5O
ôa^ aar aaÔ^J I V-JÒÒ-UÒJV
DEgIøN ?AB¡ÑrET=R9
1. CODE) AND 9TANDA'RD3 UàED IN DE9I6N:
A. INTERNATTONAL CODÊ5 (tBC & tRC) 2015
B. A9C87.16
c. NDã 2018
2. WIND LOAD1
9TRUCTURE CAIÊ,GORY:
WIND II'IPORTANCE FACTOR: 1.O
øAàIC WIND g?EED
(3 - gEcOND cU1î WIND 9?EED): 115 llPH
EXPOàURÊ, CATEOO?Y: B
3. gNOW LOAD5
FLAT ROOF 9NOW LOAD: 40 ?9F
€ROUND 9NO\V LOAD: 51.9 ?9F
9NOW EXPO5URE FACTOR, Ce: 1.O
àLOPE FACIOR, CS:
- non sliàing areasi 1.O
- sliding areasi 1.O
THERMAL FACTOR,Ct: 1.1101.O
9NOW LOAD IMPORTANCE. FACTOR : 1.O
9NO\V DEN9ITY; 25 ?CF
gNOW DRIFTINo ?E? A5CE 7.1O àEC 7,7.
9LlDlN6 gNOW ?E?A5CE7ÅO 98C7.9.
4. LIVE LOAD?
- ROOF (NON CONCURRENT): 20 PgF
5. ROOF DEAD LOAD: 15 PgF fOP CHORD, S PgF BTY
àEIàYIC D=9.IøN PARAH ETERã
àITE CI-A99
RI9KCAIÊ,OORY
IMPORTANTANCE FACÍOR
RESPONSE FACÎOR
àNORT ?EqIOD RE9PON5E ACCELERAÍION
1 gECOND REgPONgE ACCELER,ATION
àÊIàYIC DÉ5I6N CA1ÊGORY
gITE cOEFFICIENT
gITE COEFFIcIENT
MAX CON9ID=RED ãNORT E. QUAKE
MAX CONgIDERED 1 àEC E, QUAKE
SPECÍ P,AL RESPONSE ACCELER,ATI O N
àPECÍ?,AL REgPONgE ACCELE?A.TION,'1 gEC
?EqIOD PARAIIETER 1
?ERIOD PAP,AYIEÎER2
APPROXI HATE FUNDAHENTAL PERIOD (ãEC)
9EI9I1IC REgPO N 9E F AC'I OR
I
R
3s
91
Fa
Fv
àmE=Fax9E
:rml =Fvx=l9¿ê=2/3x9mâ
9à1 =2/3x9m1
CI
x
Ta=Ctxhnx
CE
U
2
1.O
VARIEC
o.244
o.o72
B
1.602
t.rot)¿
o.397
o.172
U.2(o(ê
o.115
VARIES
o.8
o.452
o.o76
IBCTABLE1604.5
1AøL=91-1AND 11.5-1
IABL=E 1-1AND 11.5-1
TAøLã12,2.1
sEcTloN'11.4.1.
gECT¡ON 11.4.1
TABLE 11.6-1&2
TAøLE11.4-1
ÍABLE11.4-2
EQUATION 11.4.1
EQUATION 11.4-2
EQUATION 11.4-3
EQUATION'11.4.4
ÏABLÊ12,8.2
ÍA'PLÊ12.2-2
-|ABLE.12.8-2
ÊQUAÍION12.8-2
IONA.L
J.
OL'
ÞacI
JOD
M126067
I ruSS
T5
rruss rype
IVONO TRUSS
ury
1
Pty
,|
.lob Reference loolionalì
so-to s-s.io 1 1-3-13 16-9-15 224-'l 27-'tO-3 33-4-6 3V2-0
5-$.10 5-6-2 5-ù2 5-è2 5-6-2 5-ô2
o.zsjz
4x4 -
4
4x4 =
6
4x4 -
7
4x6 =I
5-+10
Scale = 1:66.6
4x4 -
16
4xB -
4xB 3x4 ll
95x10 =
1
4x8
5
3x5 ll
0-G0
LOADING
TCLL
(Roof
TCDL
BCLL
4x1O =
15
4x6 =
14
6x8 -
IJ
4x6 =
12
4x6 =
11
4x6 =5x6 =
0-G0
(ps0
40.0
Snow=40.0)
15.0
0.0 -
22-4-1
BRACING-
TOP CHORD
BOT CHORD
WEBS
PLATES
MT2O
GRIP
1971144
LUMBER-
TOP CHORD 2x6 SPF 2100F l.8E
BOT CHORD 2xB DF 1950F 1.7EWEBS 2x4 SPF 1650F 1.5E *Except*
W1,W15: 2x6 SPF 1650F 1.5E
Weight: 255 lb FT = 2Oo/o
Structural wood sheathing directly applied or 4-2-7 oc purlins,
except end verticals.
Rigid ceiling directly appl¡ed or 9-11-12 oc brac¡ng.
I Row at midpt 8-10
MiTek recommends that Stab¡lizers and required cross bracing
be installed during truss erect¡on, in accordance with Stabilizer
lnstallation ouide.
REACTIONS. (lb/size) 18=167710-5-8 (min.o-1-13),10=167710-5-8 (min.0-1-13)
Max Horz I 8=73(LC 9)
Max Upl¡ft18=-21 4(LC 8),1o=-212(LC 12)
FORCES. (lb) - Max. Comp./Max. Ten. - All forces 250 (lb) or less except when shown.
TOP CHORD I -1 8=-1 602/396, 1-2=-27641664, 2-3=-436011023, 3-4=-514611201, 4-5=-49691117 1,
5-6=-4961 11 17 1, 6-7 =-3927 1938, 7 -8=-23321579
BOT CHORD 16-17=-702127 59, 15-16=-1057 14354, 14-15=-1225151 41 , 13-14=-122515141,
12-13=-1 177 14964, 1 1 -12=-92513921, 1O-1 1=-54912327
WEBS 1-17=-690/2985,2-17=-12981369,2-16=-42111806,3-16=-8201246,3-15=-2091898,
4-15=-308i138,6-12=-12131293,7-12=-1041668,7-11=-18701440,8-11=-17311031,
8-1 0=-2685/626
NOTES.
1) Wind: ASCE 7-10; Vult=11Smph Vasd=g1mph; TCDL=6.opsf; BCDL=6.0psf; h=25ft; Cat. ll; Exp
(envelope) and C-C Exterio(2) zone; cântilever leftand r¡ghtexposed ; end vertical leftand r¡ght
forces & MWFRS for reactions shown; Lumber DOL=1.00 plate grip DOL=I.00
2) TCLL: ASCE 7-10; Pf=40.0 psf (flat roof snow); Category ll; Exp C; Part¡ally Exp.; Ct=1.10
3) Provide adequate drainage to prevent water ponding.
4) Plates checked for a plus or minus 5 degree rotation about its center.
5) This truss has been designed for a I 0.0 psf bottom chord live load nonconcurrent with åny other live loads.
6) * This truss has been designed for a live load of 20.0psf on the bottom chord in all areas where a rectangle 3-6-0 tall by 2-0-0 wide
will fit between the bottom chord and any other members.
7) Provide mechanical connection (by others) of truss to bearing plate capable of withstanding 214 lb uplifi at joint 1 8 and 212 lb uplift
atjoint 10.
8) This truss ¡s designed in accordance with the 201 5 lnternational Residential Code sections R502. I 1 .1 and R802. I 0.2 and
referenced standard ANSI/TPI 1.
LOADCASE(S) Standard
C; Pr. Enclosed; MWFRS
exposed;c-c for members and
SPAC|NG- 1-4-O
Plate Grip DOL 1.00
Lumber DOL 1.00
Rep Stress lncr YES
Code lRC2015/TPl20'14
csr.
TC
BC
WB
Matrix-S
0.24
0.34
0.88
in (loc)
-0.3213-15
-0.53 13-1s0.08 10
l/defl
>999
>884
nla
L/d
240
180
nla
DEFL.
Vert(LL)
Vert(CT)
Horz(CT)
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