1901 N Fairview St & Bldg A, B, C, F & 1919 N Fairview St Bldg E - Plan

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Gregory A. Kopp, PhD, PEng Professor Boundary Layer Wind Tunnel Laboratory, Faculty of Engineering, University of Western Ontario, London, ON, N6A 5B9, Canada ____________________________________________________________________________________ January 30, 2019 Dr. Mika Jovanovic PanelClaw, Inc. 1600 Osgood St, Suite 2023 North Andover, MA, 01845 United States Re: Review of CPP wind tunnel test report 11828 for the Panel Claw 10o Tilt System Dear Dr. Jovanovic, I am writing this letter in response to your request to review the wind tunnel test report by Cermak, Peterka & Peterson (CPP) “Final Report: Wind Tunnel Tests and Load Analysis for PanelClaw roof mount 10o Tilt South-Facing, CPP Project 11828”, by Anisa Como and David Banks, dated 2019 January 28. The purpose of this review is to assess whether the approach and analysis used by CPP meets the requirements of ASCE 7-05 Section 6.6.2, ASCE 7-10 Chapter 31, ASCE 7-16 Chapter 31, ASCE 49-12, and SEAOC- PV2-2017. The requirements of ASCE 7-05, ASCE 7-10, and ASCE 49-12 are essentially identical and focus on the requirements of wind tunnel test methods. The SEAOC-PV2-2017 and ASCE 7-16 requirements are also nearly identical but have additional requirements particular to roof-mounted solar arrays wind tunnel test methods when compared to earlier standards. I would note that I have worked with Dr. Banks and Mr. Fewless on a few occasions, primarily with Dr. Banks on several wind-related committees, including the development of the SEAOC recommendations “Wind loads on low profile solar photovoltaic systems on flat roofs and in balloted proposals pertaining to wind loads on roof-mounted solar arrays for ASCE 7-16. We also published a paper together on wind tunnel testing requirements for determining wind loads on roof-mounted solar arrays (G.A. Kopp & D. Banks, 2013, Use of the wind tunnel test method for obtaining design wind loads on roof-mounted solar arrays, ASCE Journal of Structural Engineering, vol. 139(2), pp. 284-287), which helped to inform the SEAOC and ASCE 7-16 processes. I wrote a chapter of a book with Mr. Fewless pertaining to wind loads on low-rise buildings for ASCE. However, I can provide this assessment as an independent expert, since I was not involved in any way with the experimental design and analysis described in the CPP report under consideration here. I have the necessary technical expertise pertaining to wind tunnel studies of roof-mounted solar arrays to assess this report. I have conducted numerous wind tunnel studies of roof-mounted solar arrays as part of the Boundary Layer Wind Tunnel Laboratory at the University of Western Ontario. I participated in the development of SEAOC-PV2-2012 and 2017. I am a voting member of the ASCE 7 wind loads subcommittee, and in that role have guided the development of design standards for wind loads on roof- mounted solar arrays and Components & Cladding wind loads, amongst other items. I am also Chair of the ASCE 49 Standards Committee, of which Dr. Banks is a member. I have published several papers on wind effects on roof-mounted solar arrays. I was the Guest Editor for a Special Issue of the Journal of Wind Engineering and Industrial Aerodynamics (the leading wind engineering journal in the world) on Wind Effects on Roof-Mounted Solar arrays. CPP have structured their report with an alignment that matches the requirements of these standards. This structure is also used in this review, for clarity. PCC2.2.3 1901 N Fairview St & Bldg A, B, C, F & 1919 N Fairview St Bldg E 4/11/2024