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Report (9) RECEIVED „,,t„ ! - ' 1 , okto a rk 1;"*'''SolaI Cit >,1 1 3 2013 CITY OFTIGARD 3055 Clearview way BUILDING DIVISION San Mateo,CA.94402 i888I SOI-CITY 1765-24891 I www.salarcity.cOm June 4,2013 Project/Job#9721521 RE: COVER LETTER Project: Caldwell Residence 13874 SW Fanno Creek Dr Tigard,OR 97224 To Whom It May Concern, A jobsite survey of the existing framing system was performed by an audit team from SolarCity. The attached structural calculations are based on site observations and design criteria listed below: Design Criteria: -Applicable Codes = 2010 OSISC&2010 OSSC,ASCE 7-05,and 2005 NDS -Roof Dead Load = 10 psf(All MPs) -Roof Live Load = 18 psf(All MPs) -Ground/Roof Snow Load = 25 psf - Risk Category= II,Wind Speed =95 mph, Exposure Category C -Solar modules =As indicated in attached drawings. On the above referenced project,the structural roof framing has been reviewed for loading from the PV system on the roof.The structural review,including the plans and calculations only apply to the section of roof that is directly supporting the PV system and its supporting elements.After review it was determined that the existing structure requires a structural upgrade.The required upgrade is shown in the structural drawings on the SolarCity drawing set. The structural roof framing including the specified upgrades and the new attachments that directly support the gravity loading from PV modules have been reviewed and determined to meet or exceed requirements of the 2010 OSISC&2010 OSSC. Please contact me with any further questions or concerns regarding this project. Sincerely, Yoo Jin Kim, P.E. � �GIN:FiO Civil Engineer Q(4 9 t. Main: 888.765.2489,x5743 email: ykim@solarcity.com , {-ON- 13,Z�C Digitally signed by Yoo Jin Kim Date:2013.06.04 16:27:44-07'00' lo,k id 06.04.2013 .: ". i:SoiarCity 3055 Clearview Way San Mateo,CA.94402 (888;COI CITY(755-2454}I wwwsolarcity.tarn Caldwell Residence - Job # 9721521 TABLE OF CONTENTS ORDER# CONTENT 1 Table Of Contents And 1/2-Mile Vicinity Map 2 Project Information, Mounting Structure&P V System Information 3 Seismic Considerations 4 Calculation Of Design Wind Loads And Uplift Calculations 5 Calculation Of Roof Dead And Live Loads 6 Structural Framing Analysis 1 2-MILE VICINITY MAP SW Omara St ., SW Ch ood St t; } I f _ I SW Tech 4 SW McDonald St U' C r o ul .�. - Q Hall Boulevard 'T o Baptist Church SVV,c �C, ro SW Greensward Ln �'reek Loop * ci) a Fa Con ta Park s w u SW Inez St SW Bonita Rd S v C,,) - al .00k St Cf) ,b1. � -cr) rn SW Pinebrook Dr SW P\'i:P `� �' _I * co ., cb co .,, CCC)_ c 01 a'D <° =Metzger •e ( 3 . Di•italGlobe,„Metro; Portia ..• Ore•o-, State .= Care=•n s i ., , U.`� -�eolo•seal Surve 13874 SW Fanno Creek Dr,Tigard, OR 97224 • Latitude:45.417403,Longitude: -122.763488,Exposure Category:C 06.04.2013 "" Version# 12.0 7."`' SolarCity Structural Calculator PROJECT INFORMATION Project Name: Caldwell Residence AHJ: Tigard Job Number: 9721521 Building Code: 2010 OSISC&2010 OSSC System Size: 5.635 kW PV System Based On: 2009 IBC/IRC Customer Name: Caldwell, Ryan ASCE Code: ASCE 7-05 Address: 13874 SW Fenno Creek Dr Upgrades Req'd? Yes City/State: Tigard, OR Stamp Req'd? Yes Zip Code 97224 PV Designer: Luke Levin Latitude: 45.417403 Calculations: Yoo Jin Kim, P.E. Longitude: -122.763488 Reviewer: Yoo Jin Kim,P.E. SC Office: Portland EOR: Yoo Jin Kim, P.E. MOUNTING STRUCTURE & P V SYSTEM INFORMATION Mounting Structure Information Risk Category II Framing Type Stick Frame PV System Type SolarCity SleekMount•'" Roofing Material Comp Roof Tile,Reveal Tile Roofs Only NA Roof Slope 28° Rafter Spacing 24"O.C. PV System Information Total Number of Modules 23 PV Module Orientation Landscape Spanning Vents No Total Area of Array 404 sf PV Module Width 3.2 ft PV Module Length 5.4 ft Attachment Type Comp Mount Type C Minimum Eave End Setback 12" Minimum Ridge Setback 12" Tile Spanner Bar Direction Tile Roofs Only NA Tile Optimal Standoff Y-Spacinq Tile Roofs Only NA PV System Weight PV Module Weight 2.5 psf Hardware Assembly Weight 0.5 psf Total PV System Weight 3 psf SEISMIC CONSIDERATIONS Seismic Design Criteria(per USGS) Seismic Design Code ASCE 7-05 Latitude 45.4174 Longitude -122.7635 SRA at Short Period SS 0.944 USGS SRA at is Period 51 0.338 USGS Soil Site Class D IBC 1613.5.2 Seismic Design Category SDC D USGS Seismic Check Required(Ss 0.4g&SDC>D)? Yes IBC 1613.1 ALTERATION LATERAL DESIGN 10% EXCEPTION CHECK, PER IBC SECTION 3404.4 Weight of Proposed PV System PV System'Weight Area Dead Load Weight 404 sf 3 psf 1213 lbs Total Weight of PV System W(pv) 1213 lbs Weight of Roof on Existing Building Sum Area of MPs with PV 509 sf Portion of Roof Weight Area Dead Load Weight Roof 509 sf 10.0 psf 5,094 lbs Ceiling 509 sf 6.5 psf 3,311 lbs Interior Walls(Top Half) 361 sf 6.0 psf 2,167 lbs Exterior Walls(Top Half) 361 sf 11.0 psf 3,972 lbs Net Weight of Roof Under PV W(exist) 14,545 lbs Check Ifo Increase of Roof Weight/ Seismic Shear Load wo Increase of DCR of Lateral8.3% IBC Sect. Force Resisting System W(PV)1 W(exist) Increase Seismic Shear Load<10%,->[GOOD] 3404.4 Note: Seismic base shear is directly proportional to roof weight. . CALCULATION OF DESIGN WIND LOADS Wind Design Criteria Wind Design Code ASCE 7-05 Wind Design Method Partially/Fully Enclosed Method Basic Wind Speed V 95 mph Fig.6-1 Exposure Category C Section 6.5.6.3 Roof Style Gable Roof Fig.6-11B/C/D-14A/B Mean Roof Height h 25 ft Section 6.2 Least Horiz. Dim.of Building LHD 35 ft Effective Roof Slope 28° Effective Rafter Spacing 24"O.C. Effective Wind Area(1 Module) A 17.6 sf IBC 1509.7.1 Roof Wind Zone Width a 4 ft Wind Pressure Calculation Coefficients Wind Pressure Exposure KZ 0.95 Table 6-3 Topographic Factor Ka 1.00 Section 6.5.7 Wind Directionality Factor Kd 0.85 Table 6-4 Importance Factor I' 1.0 Table 6-1 Velocity Pressure qh qh = 0.00256(Kz)(Kzt)(Kd)(V^2)(I) Equation 6-15 18.6 psf Wind Zone Interior(Zone 1) Edge(Zone 2) Corner(Zone 3) Ext. Pressure Coefficient(Up) GC P(UP) -1.0 -1.2 -1.2 Fig.6-11B/C/D-14A/B Ext.Pressure Coefficient(Down) GCp(Down) 0.9 0.9 0.9 Fig.6-11B/C/D-14A/B Design Wind Pressure p p =qh(GCp) Equation 6-22 Wind Pressure Up p(up) -17.7 psf -21.4 psf -21.4 psf Wind Pressure Down p(down) 16.3 psf 16.3 psf 16.3 psf COMP ALLOWABLE ATTACHMENT SPACING (IN.)AND TRIBUTARY AREA(FTA 2) interior(Zone 1) Edge(Zone 2) Corner(Zone 3), Max Allowed Foot X-Spacing Landscape 48" 48" 48" Max Allowed X Cantilever Landscape 24" 24" 24" Max Standoff Tributary Area TribCL 13 sf 13 sf 13 sf PV Assembly Dead Load WPV° 3 psf 3 psf 3 psf DLPV PCL 39 lbs 39 lbs 39 lbs WLUP-0.6 DLPVcos(8) TCL -209 lbs -257 lbs -257 lbs Attachment Uplift Capacity Tallow 512 lbs 512 lbs 512 lbs TCLJTallow DCRLand 40.8% 50.2% 50.2% . CALCULATION OF ROOF DEAD AND LIVE LOADS Roof Dead Load Material Load Roof Category Description All MPs Roofing Material Comp Roof 5.0 psf #of Layers(Comp Roof Only) 2 Underlayment_ Roofing Paper 0.5 psf Plywood Sheathing Yes 1.5 psf Board Sheathing None 0.0 psf Rafter Size and Spacing 2 x 8 @ 24 in. O.C. 1.5 psf Vaulted Ceiling No 0.0 psf Miscellaneous Miscellaneous Items 1.5 psf Total Roof Dead Load 10 psf(All MPs) 10.0 psf Reduced Roof Live Load Symbol Value ASCE 7-05 Roof Live Load Lo 20.0 psf Table 4-1 Member Tributary Area At <200 sf Roof Slope —6/12 Tributary Area Reduction R1 1 Section 4.9 Sloped Roof Reduction R2 0.9 Section 4.9 Reduced Roof Live Load Lr Lr=Lb(R1)(R2) Equation 4-2 Reduced Roof Live Load Lr 18 psf(All MPs) 18.0 psf Ceiling Dead Load Material Load Ceiling Joist Size and Spacing 2 x 6 @ 24 in. O.C. 1.1 psf Insulation Yes 1.4 psf Finish 1/2"Gypsum Board 2.2 psf Miscellaneous Miscellaneous Items 1.7 psf Total Ceiling Dead Load 6.5 psf Interior Walls Material Load Finish(Side A) 1/2"Gypsum Board 2.2 psf Wall Studs 2 x 4 @ 16 in.O.C. 1.1 psf Insulation No 0.0 psf Finish(Side B) 1/2"Gypsum Board 2.2 psf Miscellaneous Miscellaneous Items 0.5 psf Total Interior Wall Load 6.0 psf Exterior Walls Material Load Exterior Finish Wood Siding 5.0 psf Wall Studs 2 x 4 @ 16 in.O.C. 1.1 psf Insulation Yes 1.4 psf Interior Finish 1/2"Gypsum Board 2.2 psf Miscellaneous Miscellaneous Items 1.3 psf Total Exterior Wall Load 11.0 psf GROUND/ROOF SNOW LOADS Ground Snow Load Effective Roof Slope 28° Ground Snow Load pg 25.0 i ASCE Table 7-1 Snow Load Reductions Allowed? No Code Design Roof Snow Load Over PV Modules Ps-v, 25.0 Po Design Roof Snow Load Over Surrounding Roof Ps-root 25.0 psf • LAG SCREW CAPACITY CALCULATIONS (PER AWC/NDS) Lag Screw Withdrawal Capacity in Uplift(Wind) Specific Gravity of Wood G 0.42 Number of Lag Screws 1 Lag Screw Thread Diameter D 5/16° Lag Screw Overall Length L 4" Req. Minimum Embedment Tmin 2.5" NDS Table L2 Lag Screw Embedment Length T-E 2.34" NDS Table(2 Kw Constant K„, 1800 W=KN,G(3/2)D(314) NDS Withdrawal Capacity Per In. W NDS 11.2-1 205 lb/in Total Withdrawal Capacity WT WT= W*(T'E) 480 lbs Wind Load Duration Factor CD 1.60 Allowable Wind Withdrawal Capacity Ww W ' _ (CD)W Total Allowable Wind Withdrawal W, 268 lbs Capacity Additional Safety Factor FS 1.50 Total Allowable Wind W. 512 lbs Withdrawal Capacity Note: Withdrawal Capacity Available From Testing Would Supercede the Above NDS Capacity Calculations. COMPANY PROJECT 00°°% SolarCity Corporation ' I I %Vood\jVo rkrj�J San Mateo,CA 94402 SOFTWARE FOR wOOD June 4,2013 16:26 MP1.wwb Design Check Calculation Sheet • Wood Works Sizer 9.3 Loads: Load Type Distribution Pat- Location [ft] Magnitude Unit tern Start End Start End DL Dead Full Area No 10.00 (24.0)* psf SL Snow Full Area Yes 25.00 (24.0)* psf PV DL Dead Partial Area No 0.83 15.08 3.00 (24.0)* psf *Tributary Width (in) Maximum Reactions(lbs), Bearing Capacities(lbs)and Bearing Lengths(in) : 19.33' 0' 1.33' 17' Unfactored: Dead 261 215 Snow 461 392 Factored: Total 722 607 Bearing: F'theta 713 713 Capacity Joist 1871 1069 Supports 1055 1055 Anal/Des Joist 0.39 0.57 Support 0.68 0.58 Load comb #2 #4 Length 0.50* 0.50* Min req'd 0.50* 0.50* Cb 1.75 1.00 Cb min 1.75 1.00 Cb support 1.13 1.13 Fcp sup 625 625 *Minimum bearing length setting used:1/2"for end supports and 1/2"for interior supports Lumber n-ply, D.Fir-L,No.2,2x8,2-ply(3"x7-1/4") Supports:All-Timber-soft Beam,D.Fir-L No.2 Roof joist spaced at 24.0"c/c;Total length:19.33';Pitch:6/12; Lateral support:top=full,bottom=at supports;Repetitive factor:applied where permitted(refer to online help); WARNING:Member length exceeds typical stock length of 18.0[ft] Analysis vs.Allowable Stress(psi)and Deflection(in)using NDS 2005: Criterion Analysis Value Design Value Analysis/Design Shear fv = 36 Fv' = 207 fv/Fv' = 0.17 Bending(+) fb = 1095 Fb' = 1428 fb/Fb' = 0.77 Bending(-) fb = 30 Fb' = 1424 fb/Fb' = 0.02 Live Defl'n 0.55 = L/381 0.88 = L/240 0.63 Total Defl'n 1.02 = L/205 1.17 = L/l80 0.88 1 WoodWorks® Sizer SOFTWARE FOR WOOD DESIGN MP1.wwb WoodWorks®Sizer 9.3 Page 2 Additional Data: FACTORS: F/E(psi)CD CM Ct CL CF Cfu Cr Cf rt Ci Cn LC# Fv' 180 1.15 1.00 1.00 - - - - 1.00 1.00 1.00 2 Fb'+ 900 1.15 1.00 1.00 1.000 1.200 1.00 1.15 1.00 1.00 - 4 Fb'- 900 1.15 1.00 1.00 0.997 1.200 1.00 1.15 1.00 1.00 - 2 Fcp' 625 - 1.00 1.00 - - - - 1.00 1.00 - - E' 1.6 million 1.00 1.00 - - - - 1.00 1.00 - 4 Emin' 0.58 million 1.00 1.00 - - - - 1.00 1.00 - 4 CRITICAL LOAD COMBINATIONS: Shear : LC #2 = D+S, V = 557, V design = 518 lbs Bending(+) : LC #4 = D+S (pattern: 5S), M = 2398 lbs-ft Bending(-) : LC #2 = D+S, M = 65 lbs-ft Deflection: LC #4 = (live) LC #4 = (total) D=dead L=live S=snow W=wind I=impact Lr=roof live Lc=concentrated E=earthquake All LC's are listed in the Analysis output Load Patterns: s=S/2, X=L+S or L+Lr, _=no pattern load in this span Load combinations: ASCE 7-05 / IBC 2009 CALCULATIONS: Deflection: EI = 76e06 lb-in2/ply "Live" deflection = Deflection from all non-dead loads (live, wind, snow...) Total Deflection = 1.50(Dead Load Deflection) + Live Load Deflection. Bearing: Allowable bearing at an angle F'theta calculated for each support as per NDS 3.10.3 Design Notes: 1.WoodWorks analysis and design are in accordance with the ICC International Building Code(IBC 2009),the National Design Specification(NDS 2005), and NDS Design Supplement. 2.Please verify that the default deflection limits are appropriate for your application. 3.Continuous or Cantilevered Beams:NDS Clause 4.2.5.5 requires that normal grading provisions be extended to the middle 2/3 of 2 span beams and to the full length of cantilevers and other spans. 4.Sawn lumber bending members shall be laterally supported according to the provisions of NDS Clause 4.4.1. 5.SLOPED BEAMS:level bearing is required for all sloped beams. 6.The critical deflection value has been determined using maximum back-span deflection.Cantilever deflections do not govern design.