HomeMy WebLinkAboutLETTER - PROPOSED PHOTOVOLTAIC SOLAR PANEL INSTALLATIONDaniel W. Dunzik Architect LEED-AP
370 Burnt Hill Rd. Skillman NJ. 08558 908-872-3664
StudioGdesign@comcast.net
Re: Proposed Photovoltaic Solar Panel Installation
Dear Plan Reviewer:
Roof Type:
Attachment System:
3. Solar Modules shall be UL-1703 rated. Refer to manufacturers specifications sheets.
4. Positive drainage of the system shall be so as not to void the existing roof warranty.
6. Please refer to the attached structural calculations.
Daniel W. Dunzik, RA. LEED-AP
FL. Lic. No. AR98795
5. All aspects of the installation shall comply with the Florida Administrative Code, 2020 Florida Building Code -
Residential Seventh Edition, ASCE-7-16, 2020 Florida Building Code – Energy Conservation, Seventh Edition, 2017
National Electric Code, All Local Governing County and Municipal Ordinances adopted by reference or enacted by
law. All components used meet the criteria of the Florida Solar Energy Center.
If you have any questions relating to this matter, please contact me at your earliest convenience. Thank you.
Regarding the solar panel array installation on the above referenced project please note that an inspection was
performed by a representative of the Architect/Engineer of Record, and analysis of the existing structure was
conducted. There is adequate structural capacity for the installation of the array with the following recommendations:
1. The array will be installed on the existing roof. The roof framing is constructed of 2"x6" wood trusses @24" o.c.
spanning 16' 8" with a top chord length of 16' 11" with intermediate supports at 1/2 points, making the effective longest
span equals 11' 6" with 1"x6" T&G sheathing. The new array (See Site map by contractor) will add 2.63 Lb. / Sf.
overall to the roof. The existing structure is sufficient to support the new loads associated with the additional weight &
wind resistance. No additional structural support is required for the roof structure.
2. The attachment system shall be secured to the roof and shall be in strict compliance with manufacturers printed
instructions. The attachment system shall be UL 1703 approved tested. Provide 6 mil. vapor barrier between dissimilar
metals. Provide water tight gasket and sealant at all penetrations. Attachments shall follow panel rows as specified by
the system manufacturer’s installation manual. The panel angle shall match the roof slope. Reference summary table
below:
Corrugated Metal Fastener Max Spacing (in.)
"SunModo"® & "EcoFasten" Click Fit? Attachement Systems
Please See Manufacture Specification and PV-
3.6Fastener Info:min. 5/16” x 4” long stainless-steel lags with a min.
embedment of 3” into the rafters
Certification: I have reviewed the engineering testing reports for the racking and attachments to be used on this project
and I certify that the products are capable of supporting the code required loads and are suitable for this installation
when installed in strict compliance with the manufacturers printed instructions.
February 16, 2022
Erich Barrantes
416 COCONUT AVENUE EAST
PORT ST. LUCIE, FL 34952
Daniel W. Dunzik Architect LEED-AP
370 Burnt Hill Rd. Skillman NJ. 08558 908-872-3664
StudioGdesign@comcast.net
Gravity Load Calculation Criteria
Structural Design Loads per ASCE 7-16
Dead Loads = 10 psf + 2.6 psf (new solar panels) = 12.6 psf
Roof Live Load = 20 psf
Ground Snow Load/Live Load = 0 psf
Roof Slope = 10 degrees Roof Mean Height = 15 ft
Basic Wind Speed = 160 mph Exposure = B
Wind Load Calculation Criteria
Wind Loads per ASCE 7-16, Equation 29.4-7
Using an effective wind area of 10 SF, external pressure coefficient from Figure 30.3-A-I
Array Interior:Array Edge:
Zone 1 = -50.8 psf Zone 1 = -76.2 psf
Zone 2e = -50.8 psf Zone 2e = -76.2 psf
Zone 2n = -76.2 psf Zone 2n = -114.3 psf
Zone 2r = -76.2 psf Zone 2r = -114.3 psf
Zone 3e = -76.2 psf Zone 3e = -114.3 psf
Zone 3r = -91.44 psf Zone 3r = -137.16 psf
Per section 2.4.1, ASD combo = 0.6D + 0.6W:
Array Interior:
Zone 1 = 0.6 x 2.6 psf + 0.6 x (-50.8 psf) = -28.92 psf
Zone 2e = 0.6 x 2.6 psf + 0.6 x (-50.8 psf) = -28.92 psf
Zone 2n = 0.6 x 2.6 psf + 0.6 x (-76.2 psf) = -44.16 psf
Zone 2r = 0.6 x 2.6 psf + 0.6 x (-76.2 psf) = -44.16 psf
Zone 3e = 0.6 x 2.6 psf + 0.6 x (-76.2 psf) = -44.16 psf
Zone 3r = 0.6 x 2.6 psf + 0.6 x (-91.44 psf) = -53.3 psf
Array Edge:
Zone 1 = 0.6 x 2.6 psf + 0.6 x (-76.2 psf) = -44.16 psf
Zone 2e = 0.6 x 2.6 psf + 0.6 x (-76.2 psf) = -44.16 psf
Zone 2n = 0.6 x 2.6 psf + 0.6 x (-114.3 psf) = -67.02 psf
Zone 2r = 0.6 x 2.6 psf + 0.6 x (-114.3 psf) = -67.02 psf
Zone 3e = 0.6 x 2.6 psf + 0.6 x (-114.3 psf) = -67.02 psf
Zone 3r = 0.6 x 2.6 psf + 0.6 x (-137.16 psf) = -80.74 psf
Check Attachment to Wood Truss
Use 5/16 dia. Lag screw w/ 3" embedment into 2 in. wide roof rafter
Please refer to design PV-3.6 and manufacturer specification for maximum allowable span.
February 16, 2022