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A, . <br /> Daniel W. Dunzik Architect LEED-AP <br /> 370 Burnt Hill Rd.Skillman NJ.08558 908-872-3664 <br /> StudioGdesign@comcast.net May 11,2020 <br /> Gravity Load Calculation Criteria <br /> Structural Design Loads per ASCE 7-10 <br /> Dead Loads=10 psf+2.6 psf(new solar panels)= 12.6 psf <br /> Roof Live Load=20 psf <br /> Ground Snow Load=0 psf <br /> Wind Load Calculation Criteria <br /> Wind Loads per ASCE 7-10,Ch.30 method 1 <br /> Using an area of 10 SF,wind loads from Figure 30.5-1: <br /> Zone 1=-32.3 psf Roof Slope=17 degrees Roof Mean Height=15 ft <br /> Zone 2=-56.2 psf Basic Wind Speed=140 mph <br /> Zone 3=-83.1 psf Exposure.=B <br /> Per section 2.4.1,ASD combo=D+0.6W: <br /> Zone 1=2.6 psf+0.6(-32.3 psf)_-16.8 psf <br /> Zone 2=2.6 psf+0.6(-56.2 psf)_-31.1 psf <br /> Zone 3=2.6 psf+0.6(-83.1 psf)_-47.3 psf <br /> Check Attachment to Wood Rafter <br /> Use 5/16 dia.Lag screw w/3"embedment into 2 in.wide roof rafter <br /> Lag Screw Spacing: Lag Screw Tributary Area: <br /> Zone 1= 48"o.c.max Zone 1 =(48"o.c.max)^2/144= 16 SF <br /> Zone 2= 24"o.c.max Zone 2=(24"o.c.max)^2/144=4 SF <br /> Zone 3= 24"o.c.max Zone 3=(24"o.c.max)^2/144=4 SF <br /> Lag Screw Forces: W=2661b/in(Table 12.2A,2015 NDS) <br /> Zone 1= 16.8 psf x 16 SF=269 lb < W, OK Cd=1.6(Table 2.3.2,2015 NDS) <br /> Zone 2=31.1 psf x 4 SF=124 lb < W', OK Ct= 1 (Table 2.3.3,2015 NDS) <br /> Zone 3=47.3 psf x 4 SF=189 lb < W', OK W=W x embed x Cd x Ct <br /> W'=266 lb/in x 3 in.x1.6 x 1= 1276.8 lb <br />