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TURQUOISE Engineering, LLC
Structural Engineering, Design & Testing, CA#28948, NOA#13-0222.02
6915 Washington Rd,W Palm Beach, FL 33405/Ph. (561)804-9908/Fax(561) 804-9907/e-mail:turginc@aol.com
December 16, 2015
TO: St Lucie County/ Building Department
FROM: Riza N. ALTAN, P.E.
SUBJECT: Wind Uplift & Flat Re-Roofing Specifications
ADDRESS: WARD Residence /207 N 37th Street, Ft Pierce, FL 34947
CONTRACTOR:Larry Neese LLC, Roofing & Waterproofing
PERMIT#:
Dear Sir;
The re-roofing specifications for low-sloped areas of the subject residence have been
reviewed by myself. The purpose of this letter is to determine the wind uplift pressures
and specify attachment of self-adhered base sheet.
The existing low-sloped roof is located in Exposure C area at a mean roof height of 15 ft.
The roof consists of 5/8" CDX plywood deck, having positive drainage. Roof design
pressures; as per 2014 Florida Building Code, ASCE 7-10, 160 MPH ultimate Wind
Velocity for Risk Category II in Exposure C area, using Wind Load Factor of o.6 for ASD;
are determined as follows:
Field Pi = -44 psf / Perimeter (4' wide) P2= -74 psf / Corner (4'x4') P3= -111 psf.
The proposed Polyglass Self-Adhered Bitumen Roof System over Wood Decks
(#FL1654-R16) consists of sealed plywood seams using 4" wide Polyflex SAN tapes
followed by rolled-pressed Polyflex SA Base base sheet and torched-down PolyFlex G
cap sheet.
The max. design pressure of-135 psf (Wood Deck, Non-Insulated, Table 1F, Syst Type F,
Syst no.: w-53, pg. 9/36) is determined to satisfy roof uplift pressures in all roof zones.
Therefore, this letter is to certify that installation of Polyglass Self-Adhered Roof System
(#FL1654-R16) with torched-down cap sheet over wood decks, as described above,
conforms to requirements of 2014 Florida Building Code which specifies 160 MPH
ultimate wind velocity for Risk Category II in Exposure C area.
If you have any questions regarding this matter or I may be of further assistance, please
do not hesitate to call me.
Sincerely,
Riza N. ALTAN, P.E. # 85 0�® ��cFNs�• `��
Consulting Engineer
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