HomeMy WebLinkAboutMISC EMAILECEIVED CiAR 03 2017
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
February 26, 2017
TO: St Lucie County / Building Department ,, ,,
FROM: Riza N. ALTAN, P.E. sFt `?u 3d t�f
SUBJECT: Wind Uplift & Flat Re -Roofing Specifications �l 4'
ADDRESS: RADIO TOWER CONTROL Stations{ �iJ�"
900 N Rock Rd., Ft Pierce, FL 34945
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CONTRACTOR:Larry Neese Roofing, LLC
Dear Sir;
SCANNED
BY
St. Lucie Countv
The re -roofing specifications for flat area of the subject prefabricated, precast concrete
structures are reviewed by myself. The purpose of this letter is to determine the wind
uplift pressures and specify method of installation of the self adhered re -roofing system.
The existing flat roof is located in Exposure C area, at a mean roof height of 15 ft. The
roof consists of 31/2" thick structural concrete slab, having positive drainage. Roof
design pressures; as per 2014 Florida Building Code, ASCE 7-10, 170 MPH ultimate Wind
Velocity for Risk Category II in Zone Exposure C, 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 Concrete Decks
(#FL1654-R19) consists of PG100-primed and adhered PolyFlex SA Base sheet, followed
by torch -applied PolyFlex GTA cap sheet.
It is determined that the max. design pressure of -315 psf (as per Table 3B, System Type
F and System No.: C-71, page 33/45) satisfies wind pressures at all zones.
Therefore, this letter is to certify that installation of Polyglass ((#FL1654-R19) Self -
Adhered Roof System over Concrete Deck, as described above, conforms to
requirements of 2014 Florida Building Code which specifies 170 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,
dJ _7�A N
Riza N. ALTAN, P. 521
Consulting Enginee
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No, 38527 �-
s .ate STATE OF 1
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