Correspondence (45) Monday, January 02, 2006 2:27 PM Peter Drake 503 - 654 -4642 3v` p .01
J
PETER DRAKE, ARCHITECT
I
r ,
11205 8.E. HOME AVE
MILWAUKIE, OR 97222
(5D3) -4642
EmailTodarchOcomcast. net
3 Jan 2006
City Of Tigard
Inspector Dan
503 -624 -3681
RE: JohnsonlHall Addition and Remodel at 9095 SW 66
MST 2006 -00130
Dan,
I was asked to provide a calculation for the new floor joists that was used in this project. Original
plans called out 2x12 #1 or better @ 16" O.C., but owner ended up using 2x12 #2 or better @
16" O.C. My calculation uses a 40# LL and 15 # DL. You will see that the joists are adequate by
15 %.
Please include these calculations with the permit set and sign off the framing inspection.
If you need to talk to me directly during the day, l can be reached at the City Of Portland at 823-
7717.
Tpank. obi
411 i 11
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Architecture Interiors Planning
Monday, January 02, 2006 2:27 PM Peter Drake 503 - 654 -4642 p.02
Floor Joist( 98 International One -and Two - Family Dwelling Code (97 NOS) 1 Ver: 5.05
By: Peter Drake, Architect , Peter Drake, Architect on: 12 -31 -2005: 09:51:43 AM
Protect: Joanscat - Location: Floor joists
Summary:
1.5 IN x 11.25 IN x 16.08 FT Q 16 O.C. / #2 - Douglas Fir -Larch - Dry Use
Section Adequate By: 15.1% Controlling Factor: Section Modulus / Depth Required 10.48 In
Center Span Deflections: DLO -Center= 0.11 IN
Dead Load: LLD- Center= 0.28 IN = L/685
Total l Load: Loaoa : d: TLD- Center= 0.39 IN = U498
To
Center Span Left End Reactions (Support A): LL Rxn -A� 429 L8
Dead Load: ea
Load: DL_� -A= 161 LB
B
Total Load: TL-Rxn-A 590 L6
Bearing Length Required (Beam only, Support capacity not checked): BL-A. 0.63 IN
Center Span Right End Reactions (Support By LL- Rxn -6= 429 LB
Lea Load: DL_�_S= 161 LB
Total Load; Dead Load: TL Rxn - B= 590 LB
T
Bearing Length Required (Beam only, Support capacity not checked): BL -6= 0.63 IN
Joist Data:
1.2= 16,08 FT
Center Span Length:
Floor sheathing applied to top Of Joists -top of joists fully braced. 1 Cd= 00
Live Load Duration Factor. =
Live Load Deflect. Criteria: L/ 360
Total Load Deflect. Criteria:
Center Span Loading:
Uniform Floor Loading:
LL-2= 40.0 PSF
Dead Load: a Load: DL -2= 15.0 PSF
e
Total Load: TL -2= 55.0 PSF Total Load Adjusted for Joist Spacing: w T_2= 73 PLF
Properties For #2- Douglas Fir -Larch = 900 PSI
Bending Stress: FFb 95 PSI
Shear Stress: v= 1600000 PSI
Modulus of Elasticity: Er--
625 PSI
Stress Perpendicular to Grain:
Adjusted Properties Fb'= 1035 PSI
Fb' (Tension):
Adjustment Factors: Cd =1.00 Cf=1.00 Cr =1.15 '� 95 PSI
Fv': Re=
Adjustment Factors: Cd =1.00
Design Requirements: M= 2370 FT -t8
Controlling Moment:
8.04 Ft from left support of span 2 (Center Span)
Critical moment created by combining all dead loads and live loads on span(s) 2 V= 590 LB
controlling Shear,
At right support of span 2 (Center Span)
Critical shear created by combining all dead Toads and live toads on span(s) 2
Comparisons With Required Sections: S 27.48 IN3
SeGtlon Modulus ( Moment): S= 31.134 INS
Area (Shear): Amor: 9.31 IN2
A= 16.88 IN2
Moment of inertia (Deflection): Iraq= 128,61 1N4
1= 177.95 IN4
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Monday, January 02, 2006 2:27 PM Peter Drake 503 -654 -4642 p.03
Floor Joist[ 98 International One -and Two - Family Dwelling Code (97 NDS) ) Ver. 5.05
By: Peter Drake, Architect , Peter Drake, Architect on: 12 -31 -2005
Project: Joanscot - Location: Floor joists
Summary:
1.5 IN x 11:25 IN x 16,08 FT 16 O.C. 1 #2 - Douglas Fir -Larch - Dry Use
Section Adequate By: 15.1% Controlling Factor: Section Modulus 1 Depth Required 10.48 In _
SHEAR, MOMENT, AND DEFLECTION DIAGRAMS
Load combination shown: Controlling . Shear /MomenUDeflection Diagrams
600 • 590 lbs g 0 if
300 •
Shear -
(lbs) 0
-300 - .•
-600 - __590 lbs aQ 16 f(
3000 2370 ft -lbs 8 ft
1500 -
Moment
(ft-lb) 0 - -- - 4
-1500 -
-3000
-.5
-.25 -
Deflection
(in) 0 - -
.25 -
. '-.387in 8ft
Center Span = 16.08 ft
Controlling Load Cases:.
Shear: Critical shear created by combining all dead toads and live loads on span(s) 2
Moment: Critical moment created by combining all dead loads and live Toads on span(s) 2
Deflection: Critical deflection created in combining all dead Toads and live toads on span(a) 2 _.. _ _...
LOADING DIAGRAM
A
w
�......
Center Span = 16.08 ft
Reactions
Live Load Dead Load Total Load Uplift Load
A 429 Lb 181 LD 590 Lb 0 Lb
8 429 Lb 161 Lb 590 Lb 0 Lb
Cant S pan
Uniform Loading
Live Load Dead Load Total Load