REVIEWED BLD2023-0778+Structural_Analysis_or_Calculations+6.20.2023_2.18.46_PM+3619885REVIEWED ,.,.,.,.,.
BY
CITY OF EDMONDS
BUILDING DEPARTMENT
January 12, 2022
P7
structural
ENGINEERS
RECEIVED
Jun 21 2023
CITY OF EDMONDS
DEVELOPMENT SERVICES
DEPARTMENT
BLD2023-0778
Unirac
1411 Broadway Blvd. NE
Albuquerque, NM 87102
Attn.: Unirac- Engineering Department
Re: Engineering Certification for the Unirac U-Builder 2.0 SOLARMOUNT Flush Rail
PZSE, Inc. - Structural Engineers has reviewed the Unirac SOLARMOUNT rails, proprietary mounting system constructed
from modular parts which is intended for rooftop installation of solar photovoltaic (PV) panels; and has reviewed the U-
builder Online tool. This U-Builder software includes analysis for the SOLARMOUNT LIGHT rail, SOLARMOUNT
STANDARD rail, and SOLARMOUNT HEAVY DUTY rail with Standard and Pro Series hardware. All information, data and
analysis contained within are based on, and comply with the following codes and typical specifications:
1. Minimum Design Loads for Buildings and other Structures, ASCE/SEI 7-05, ASCE/SEI 7-10, ASCE/SEI 7-16
2. 2006-2018 International Building Code, by International Code Council, Inc. w/ Provisions from SEAOC PV-2 2017.
3. 2006-2018 International Residential Code, by International Code Council, Inc. w/ Provisions from SEAOC PV-2
2017.
4. AC428, Acceptance Criteria for Modular Framing Systems Used to Support Photovoltaic (PV) Panels, November
1, 2012 by ICC-ES.
5. 2015 Aluminum Design Manual, by The Aluminum Association, 2015
Following are typical specifications to meet the above code requirements:
Design Criteria: Ground Snow Load = 0 - 100 (psf)
Basic Wind Speed = 85 - 190 (mph)
Roof Mean Height = 0 - 60 (ft)
Roof Pitch = 0 - 45 (degrees)
Exposure Category = B, C & D
Attachment Spacing: Per U-builder Engineering report.
Cantilever: Maximum cantilever length is L/3, where "L" is the span noted in the U-Builder online
tool.
Clearance: 2" to 10" clear from top of roof to top of PV panel.
Tolerance(s): 1.0" tolerance for any specified dimension in this report is allowed for installation.
Installation Orientation: See SOLARMOUNT Rail Flush Installation Guide.
Landscape - PV Panel long dimension is parallel to ridge/eave line of roof and the PV
panel is mounted on the long side.
Portrait - PV Panel short dimension is parallel to ridge/eave line of roof and the PV panel
is mounted on the short side.
1478 Stone Point Drive, Suite 190, Roseville, CA 95661
916.961.3960 916.961.3965 v www.pzse.com
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ENGINEERS
Components and Cladding Roof Zones:
The Components and Cladding Roof Zones shall be determined based on ASCE 7-05, ASCE 7-10 & 7-16 Component and
Cladding design.
Notes: 1) U-builder Online tool analysis is only for Unirac SM SOLARMOUNT Rail Flush systems only and do not
include roof capacity check.
2) Risk Category II per ASCE 7-16.
3) Topographic factor, kzt is 1.0.
4) Array Edge Factor YE = 1.5
5) Average parapet height is 0.0 ft.
6) Wind speeds are LRFD values.
7) Attachment spacing(s) apply to a seismic design category E or less.
Design Responsibility:
The U-Builder design software is intended to be used under the responsible charge of a registered design professional
where required by the authority having jurisdiction. In all cases, this U-builder software should be used under the
direction of a design professional with sufficient structural engineering knowledge and experience to be able to:
Evaluate whether the U-Builder Software is applicable to the project, and
Understand and determine the appropriate values for all input parameters of the U-Builder software.
This letter certifies that the Unirac SM SOLARMOUNT Rails Flush, when installed according to the U-Builder engineering
report and the manufacture specifications, is in compliance with the above codes and loading criteria.
This certification excludes evaluation of the following components:
1) The structure to support the loads imposed on the building by the array; including, but not limited to: strength
and deflection of structural framing members, fastening and/or strength of roofing materials, and/or the effects
of snow accumulation on the structure.
2) The attachment of the SM SOLARMOUNT Rails to the existing structure.
3) The capacity of the solar module frame to resist the loads.
This requires additional knowledge of the building and is outside the scope of the certification of this racking system.
If you have any questions on the above, do not hesitate to call.
Prepared by:
PZSE, Inc. —Structural Engineers
Roseville, CA
DIGITALLY SIGNED
EXPIRES 08/02/2.023
1478 Stone Point Drive, Suite 190, Roseville, CA 95661
916.961.3960 , 916.961.3965 v www.pzse.com 2 of 2
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JVA, Incorporated
1319 Spruce Street
Boulder, CO 80302
September l9, 2022
Jacob Keith
McKinstry
16025 Table Mountain Parkway # 100
Golden, CO 80403
RE: Structural Verification for PV Installation on City of Edmonds Public Safety Complex
Located at 250 5"' Ave N
Edmonds, WA
JVA Project # 21538
Dear Jacob:
303.444.1951
info®jvajva.com
www.jvajva.com
JVA, Inc. has performed a structural investigation to evaluate the ability of the existing roof structure to support the
superimposed dead and transferred wind loads associated with the photovoltaic (PV) system proposed for installation
on the referenced building in combination with existing loads as required by the 2018 International Building Code as
adopted by the State of Washington Building Code Council. The racking system for the proposed array will be
designed by the manufacturer and will have a maximum average weight of 4.0 pounds per square foot (psf). JVA's
analysis is limited to the existing roof structure and does not include analysis of the racking systems.
We were provided with structural construction drawings for the original building dated 1998 which show the roof
structure to primarily consist of premanufactured wood trusses spanning between bearing walls. A portion of the roof
has manufactured wood joists spanning between glulam beams.
The system will be designed to meet the wind loading criteria and minimum loading requirements as established by
ASCE 7-16 for 25 psf ground and roof snow load and 110 mile -per -hour ultimate wind speed, exposure B and Risk
Category IV per the requirements of the Building Code. Seismic loadings will also be considered in the design, with
design criteria that meet or exceed the requirements currently adopted.
The flush mounted PV system will not introduce additional snow load to the existing roof framing. Connections to the
roof structure shall be spaced at a maximum of 4'-0 on center and adjacent rows of racking shall have their connections
to the roof staggered. Provided that this connection pattern is followed, our analysis indicates that the existing roof
structure has adequate capacity to support Code -required loads combined with the added dead and wind loads
associated with the proposed PV arrays. Additionally, the array will not increase the lateral demands on any member
beyond their design capacity. JVA has reviewed the potential for snow drift and determined that the drift will not
impact the load capacity of the roof for the PV installation.
The PV installer is responsible for coordination of all work, surveying and inspecting existing structures, and
reporting any discrepancies prior to proceeding.
Please contact us if you have questions or concerns.
Sincerely,
JVA, INCORPORATED
f
Reviewed
By: By:
$rctt A. Robinson
Senior Project Manager
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B O U L D E R FORT COLLI N S W I N T E R P A R K G LENWOOD SPRINGS D E N V E R