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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
August 01, 2016
TO: St Lucie County/ Building Department
FROM: Riza N. ALTAN, P.E.
SUBJECT: Wind Uplift & Flat Re-Roofing Specifications
ADDRESS: GARDNER Residence/211 N 40th St., Ft Pierce, FL 34947
CONTRACTOR:Larry Neese LLC, Roofing & Waterproofing
AUG 0 5 4f
PERMITT IVIG
Dear Sir; St. Lucie county, FL
The re-roofing specifications for flat 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 26'-x28' flat roof is located in Exposure C area at mean roof height of 15 ft.
The roof consists of 19/32" 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 0.6 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-R19) consists of sealed plywood seams using 4" wide Polyflex SA-V tapes
followed by rolled-pressed Polyflex SA Base base sheet and heat-welded PolyFlex G
granule cap sheet.
The max. design pressure of-135 psf (Wood Deck, Non-Insulated, Table 1G, Syst Type F,
Syst#W-142, pg. 22/45) 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-R19) with .torch-applied cap sheet over wood decks, as described above,
conforms to requirements of 20.14 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.
f Sincerely,
r
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