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Specifications (47) V\-NST it - 6 gg F .A zr VECTDRSEP 9 2019 E t"i G I 1-'1 EERS c y r A no BUILDING DIVISION VSE Project Number:U1839-0957-191 September 6,2019 Auric Energy 2310 South 1300 West Salt Lake City,UT 84119 REFERENCE: Schichun Ho Residence: 16854 Southwest Friendly Lane,Beaverton,OR 97007 Solar Array Installation To Whom It May Concern: Per your request, we have reviewed the existing structure at the above referenced site. The purpose of our review was to determine the adequacy of the existing structure to support the proposed installation of solar panels on the roof as shown on the panel layout plan. Based upon our review, we conclude that the existing structure is adequate to support the proposed solar panel installation. Design Parameters Code:Oregon Structural Specialty Code,2014 Edition(2012 IBC) Risk Category:II Design wind speed: 120 mph (3-sec gust)per ASCE 7-10 Wind exposure category:C Ground snow load: 10 psf Existing Roof Structure Roof structure:2x4 manufactured trusses @ 24"O.C. Roofing material:asphalt shingles Max.framing span: 51'-4" Roof slope:30° Conclusions Based upon our review,we conclude that the existing structure is adequate to support the proposed solar panel installation. In the area of the solar array,other live loads will not be present or will be greatly reduced.The member forces in the area of the solar panels are not increased by more than 5%; thus,the stresses of the structural elements are not increased by more than 5%. Therefore, the requirements of Section 3403.3 of the 2014 OSSC are met and the structure is permitted to remain unaltered. The solar array will be flush-mounted (no more than 6" above the roof surface) and parallel to the roof surface. Thus, we conclude that any additional wind loading on the structure related to the addition of the proposed solar array is negligible. Regarding seismic loads, we conclude that any additional forces will be small. Conservatively neglecting the weight of existing wall materials, the installation of the solar panels represents an increase in the total weight (and resulting seismic load)of 3.8%. Because the increase in lateral forces is less than 10%,this addition meets the requirements of the exception in Section 3403.4 of the 2014 OSSC.Thus the existing lateral force resisting system is permitted to remain unaltered. 651 W.Galena Park Blvd.,Ste. 101/Draper,UT 84020/T(801)990-1775/F(801)990-1776/www.vectorse.com VSE Project Number:U1839-0957-191 Schichun Ho Residence V ECT' O R 9/6/2019 E n Q l n E E R s Limitations Installation of the solar panels must be performed in accordance with manufacturer recommendations. All work performed must be in accordance with accepted industry-wide methods and applicable safety standards. The contractor shall notify Vector Structural Engineering,LLC should any damage, deterioration or discrepancies between the as-built condition of the structure and the condition described in this letter be found.Connections to existing roof framing must be staggered, except at array ends, so as not to overload any existing structural member. The use of solar panel support span tables provided by others is allowed only where the building type, site conditions, site-specific design parameters, and solar panel configuration match the description of the span tables. The design of the solar panel racking (mounts, rails, etc.), the connection of the racking to the roof and electrical engineering is the responsibility of others.Waterproofing around the roof penetrations is the responsibility of others.Vector Structural Engineering assumes no responsibility for improper installation of the solar array. VECTOR STRUCTURAL ENGINEERING,LLC ,0 CTUR4 BRED P ROF4.s \r_) F, NE ND cf, Seo c, 93806PE Digitally Signed ,OREGON Digi iy gned by WeIIs Holmes GG�I c/(/ 1O' 9 \\�—J DN CN Wcl�s Holmes, (� Wells Holmes OUVECTOH ST O00 TURALE5656NE057B8 LLC,C=US - L IND " Date 2019.09.06 17:59:10-06'00' EXPIRES: 6/30/2021 09/06/2019 Wells Holmes,S.E. OR License:93806PE-Expires:06/30/2021 Project Engineer Enclosures WLH/yjd 651 W.Galena Park Blvd.,Ste. 101/Draper, UT 84020/T(801)990-1775/F(801)990-1776/www.vectorse.com • . , JOB NO.: U1839-0957-191 VEcr0 n G i n E >= R s SUBJECT: WIND PRESSURE PROJECT: Schichun Ho Residence Components and Cladding Wind Calculations Label: Solar Panel Array Note: Calculations per ASCE 7-10 SITE-SPECIFIC WIND PARAMETERS: Basic Wind Speed [mph]: 120 Notes: Exposure Category: C Risk Category: II .. ,w-a.:,..- ,--.,.., ADDITIONAL INPUT & CALCULATIONS: Height of Roof, h [ft]: 25 (Approximate) Comp/Cladding Location Gable Roofs 27°< 0 5.450 Enclosure Classification: Enclosed Buildings Zone 1 GCp: 1.0 Figure 30.4-2C (enter largest abs. value) Zone 2 GCp: 1.2 (enter largest abs. value) Zone 3 GCp: 1.2 (enter largest abs. value) a: 9.5 Table 26.9-1 zg [ft]: 900 Table 26.9-1 Kh: 0.95 Table 30.3-1 KZt: 1 Equation 26.8-1 Ka: 0.85 Table 26.6-1 Velocity Pressure, qh [psf]: 29.6 Equation 30.3-1 GCp,: 0 Table 26.11-1 OUTPUT: p= qh[(GCp)—(GCp,)J Equation 30.9-1 Zone 1 Pressure, p[psf]: 29.6 psf(1.0 W, Interior Zones*) Zone 2 Pressure, p [psf]: 35.5 psf(1.0 W, End Zones*) Zone 3 Pressure, p [psf]: 35.5 psf(1.0 W, Corner Zones*within a) (a= 3 ft) i JOB NO.: U1839-0957-191 VECTORSUBJECT: SEISMIC LOADS E n o I n E E R s PROJECT: Schichun Ho Residence COMPARE WIND&SEISMIC LOADS FOR CONNECTION (1 Sq. Ft. Section) Wind Load, W: Wind pressure, p: 17.8 psf(Zone 1: 0.6 W from wind pressure calculation) Height, h: 1.0 ft Width, w: 1.0 ft Fperp: 17.8 lb (Uplift) Wind Controls Connection Design Seismic Load, E: Risk category: li Fa: 1.1 Seismic Design Category: D Fv: 1.6 Ip 1.00 SMS: 1.068 Site Class: D SM1: 0.668 Rp: 1.5 SDS: 0.712 Ss: 0.956 SD1: 0.445 Si: 0.424 ap: 1 0.7* Fp,min: 0.374 lb z: 1.0 ft 0.7* Fp,max: 1.994 lb h: 1.0 ft 0.7 * Fp,vert: 0.249 lb z/h: 1.0 0.7 * Fp,long: 0.997 lb 0.7*Fp,perp: 0.714 lb (uplift) CHECK INCREASE IN OVERALL SEISMIC LOADS SEISMIC: Estimated Roof Dead Load 13.5 psf Solar Dead Load 2.5 psf Total Dead Load 14.0 psf % Coverage 20% Addt'I Seismic Weight 3.8% Conservatively neglecting the weight of existing wall materials, the installation of the solar panels represents an increase in the total weight(and resulting seismic load)of 3.8%. Because the increase is less than 10%, this addition meets the requirements of the exception in Section 3403.4 of the 2014 OSSC. Thus the existing structure is permitted to remain unaltered. s JOB NO.: U1839-0957-191 VECTOR SUBJECT: CONNECTION E n G I n E ER S PROJECT: Schichun Ho Residence Lag Screw Connection Capacity: Demand: Lag Screw Size [in]: 5/16 Max. Trib. Cd: 1.6 NDS Table 2.3.2 Pressure Max d (0.6 Wind) Tributary Area2 Max. Uplift Embedment' [in]: 2.5 (psf) Width (ft) (ft2) Force (lbs) Grade: SPF (G = 0.42) Zone Capacity [lbs/in]: 205 NDS Table 12.2A 1 17.8 4.0 11.0 195 Number of Screws: 1 2 21.3 4.0 11.0 235 Prying Coefficient: 1.4 3 21.3 4.0 11.0 235 Total Capacity [lbs]: 586 Demand< Capacity: CONNECTION OKAY 1. Embedment is measured from the top of the framing member to the beginning of the tapered tip of the lag screw. Embedment in sheathing or other material is not effective.The length of the tapered tip is not part of the embedment length. 2. 'Max.Trib Area'is the product of the'Max.Tributary Width' (along the rails)and 1/2 the panel width/height (perpendicular to the rails). JOB NO.: U1839-0957-191 * ECTOR SUBJECT: GRAVITY LOADS r1 G I rl E E R S PROJECT: Schichun Ho Residence CALCULATE ESTIMATED GRAVITY LOADS Increase due to Original ROOF DEAD LOAD (D) pitch loading Roof Pitch/12 6.9 Asphalt Shingles 2.5 1.15 2.0 psf 1/2" Plywood 1.5 1.15 1.0 psf Framing 3.5 psf Insulation 1.5 psf 1/2" Gypsum CIg. 3.0 psf M, E & Misc 1.5 psf DL 13.5 psf PV Array DL 2.5 psf ROOF LIVE LOAD (Lr) Existing Design Roof Live Load [psf] 20 ASCE 7-10, Table 4-1 Roof Live Load With PV Array [psf] 0 w/ Solar Panel SNOW LOAD (S): Existing Array Roof Slope [x:12]: 6.9 6.9 Roof Slope [°]: 30 30 Snow Ground Load, pg [psf]: 10 10 ASCE 7-10, Section 7.2 Terrain Category: C C ASCE 7-10, Table 7-2 Exposure of Roof: Fully Exposed Fully Exposed ASCE 7-10, Table 7-2 Exposure Factor, Ce: 0.9 0.9 ASCE 7-10, Table 7-2 Thermal Factor, Ct: 1.1 1.1 ASCE 7-10, Table 7-3 Risk Category: Il II ASCE 7-10, Table 1.5-1 Importance Factor, Is: 1.0 1.0 ASCE 7-10, Table 1.5-2 Flat Roof Snow Load, pf[psf]: 7 7 ASCE 7-10, Equation 7.3-1 Minimum Roof Snow Load, pm [psf]: 20 20 ASCE 7-10, Section 7.3.4 Unobstructed Slippery Surface? No Yes ASCE 7-10, Section 7.4 Slope Factor Figure: Figure 7-2b Figure 7-2b ASCE 7-10, Section 7.4 Roof Slope Factor, Cs: 1.00 0.67 ASCE 7-10, Figure 7-2 Sloped Roof Snow Load, Ps [psf]: 7 5 ASCE 7-10, Equation 7.4-1 Design Snow Load, S [psf]: 20 20 JOB NO.: U1839-0957-191 )VECTOR SUBJECT: LOAD COMPARISON E t"1 e I r"i E E R S PROJECT: Schichun Ho Residence Side with (4) panels Summary of Loads Existing With PV Array D [psf] 14 16 Lr[psf] 20 0 S [psf] 20 20 Maximum Gravity Loads: Existing With PV Array (D + Lr)/Cd [psf] 27 18 ASCE 7-10, Section 2.4.1 (D+S)/Cd [psf] 29 31 ASCE 7-10, Section 2.4.1 (Cd=Load Duration Factor=0.9 for D,1.15 for S,and 1.25 for Lr) Maximum Gravity Load [psf]: 29 I 31 Maximum Member Forces: LOCATION House GEOMETRY Span(ft) 51.3 (Approximate) Solar Panel Array Start, a (ft) 0.6 (Approximate) Solar Panel Array Length, b (ft) 22.3 (Approximate) Truss/Rafter Spacing (ft) 2.0 MEMBER FORCES Existing With PV Array Ratio Vertical Reaction,V1 (lbs) 1495 1570 105% OK Vertical Reaction, V2 (lbs) 1495 1517 101% OK Existing With PV Array Ratio Moment @ Center, M (lbs-ft) 19188 I 19754 103% OK The member forces in the area of the solar array are not increased by more than 5%; thus,the stresses of the structural elements are not increased by more than 5%. Therefore,the requirements of Section 3403.3 of the 2014 OSSC are met and the structure is permitted to remain unaltered. C TO RJOB NO.: 9-0957-191 SUBJECT: MEMBER MEMBER FORCES E n G I n E E R S PROJECT: Schichun Ho Residence Side with(3)panels DESIGN LOADS: Load Types: Snow Live Dead Existing Roof 20 20 14 Proposed PV Array 20 0 16 Label manufactured trusses Length 51.33 Existing Proposed Check M(ft-Ib) 22066 22592 1102% OK Existing Proposed Check V(lb) 1720 1782 1104% OK The member forces in the area of the solar panels are not increased by more than 5%;thus,the stresses of the structural elements are not increased by more than 5%.Therefore,the requirements of Section 3403.3 of the 2014 OSSC are met and the structure is permitted to remain unaltered. LOAD(LB) Existing Loads —EXISTING PROPOSED Add'l Add'I 80 Live Dead 70 MIMI IIIIIMINENS Roof Load Load Bm wt 60 Cond Trib(ft) (plf) (plf) (p11) wLL(plf) woL(plf) 50 1 2.00 0 0 0 40.0 27.0 40 30 20 Proposed Loads(Distributed) 10 Length Dist to of o 10 20 30 40 50 60 Load Load A wLL 0 wDL Cond 'a'(ft) 'b'(ft) (plf) (plf) 2 1 6 0.0 5.0 SHEAR(LB) 3 12 11 0.0 5.0 2000 EXISTING - PROPOSED 4 1500 5 1000 6 500 0 Proposed Loads as Point Loads -500 0 10 20 40 50 60 Point Point -1000 Live Dead -1500 Load Load -2000 Dista' PLL PDL' Cond (ft) (Ib) (Ib) 7 MOMENT(FT-LB) 8 - ,n.EXISTING -•-----PROPOSED 9 25000 10 11 20000 f J s 15000 10000 +` I 5000 0 2 0 10 20 30 40 50 60 . • E C 0 R JOB NO.: U1839-0957-191 VE n O I n E E R S SUBJECT: SOLAR LAYOUT PROJECT: Schichun Ho Residence FITS 27 MODULES ❑ ❑ ❑ ❑ M SP1 Ill ° ❑ ❑ ❑ 0 0 0 ❑ 0 , \ \ ' \ , \ ' \ , \ \ El ❑ o A P1 P1 P1 P1 P1 P1 \ 0 P1 P1 P1 P1 P1 P1 P1 \ \ ❑ P1 P1 P1 P1 P1 \ ❑ \ P1 P1 P1 P1 P1 P1 P1 P1 P1 \ r 42'-0"