HomeMy WebLinkAboutLetter; Ciuperger - Residential PV Roof Mount InstallationGODWIN ENGINEERING AND DESIGN, LLC
8378 Foxtail Loop, Pensacola, FL 32526 1 (850)712-4219 1 chadCa)godwineng com
November 14, 2019
To: St. Lucie County Building Division
2300 Virginia Avenue
Ft. Pierce, FL 34982
Re: Ciuperger - Residential PV Roof Mount Installation
15370 Skyking Drive
Port St. Lucie, FL 34987
Plan Reviewer,
E
TPerm�thn
i
This letter is regarding the installation of a new roof mounted Solar PV System on the existing
residential structure at the address above. I have reviewed the attachment plan and have
determined that the roof mounted PV system is in compliance with the applicable sections of the
following Codes as amended and adopted by the jurisdiction:
2017 Florida Building Code 6th Edition, FBC
ASCE 7 Min. Design Loads for Buildings & Other Structures
Per 2017 FBC, the Roof Mounted PV system will be subject to the following design criteria:
Design Wind Speed(V i,) - 160mph 3sec gust, Exposure Category - C
The PV System consist of the modules, railing, and connection hardware. The system will add a
dead load of approximately 3 psf to the roof.
The existing roof covering is Asphalt Shingle with min. 1h'! plywood decking and 2" x 4" roof trusses
24" O.C. The roofing, decking, and roof trusses are in good condition. The existing structure will be
adequate for supporting the additional PV dead load and ind loads.
The securement method of the PV system is to be Flush mounted to the asphalt shingle roof with
Ironridge railing and the Roof -Tech RT mini mount. The attachments can be attached up to 48"
apart and should be staggered, where possible, to allow distribution of the design loads evenly to
the structure. The mounts shall be installed with a min. 2 J 5.0 x 60mm wood screws with minimum
2" thread length directly to roof truss.
ST.LUCIE COUNTY
Please see attached documents and contact me dP1dlNdtpwibave any questions.C.
FILE CC) BLDG: \\\D#N`tCEpGo�
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Sincerely, ELE�'�/ _ * .8 360 ;
D. Chad Godwin, PE 81360 DATE:/1�7-Y'5 =-a ; * —
Exp.02/28/2021 PLUMB: ®` S TEOF '1-
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BUILDING DESIGN PROPERTIES
SYMBOL VALUE
UNIT
BASICWINDSPEED
V
160
mph
Figure 26.5.1C, page 249a
ROOF PITCH
0
>)[02) iF
degrees
MEAN ROOF HEIGHT
It
ROOFSETBACK
Lt
ADJUSTMENT FACTOR FOR BUILDING
HEIGHTANO EXPOSURE
Qa3
Figure 30.5.1, pg 347
TOPIGRAPHICAL FACTOR
Figure 26.8-1, pg 252
EXPOSURE
EFFECT-VEWINDAREA
sf
ZONEI
ZONE2 20NE3
VARIABLE DESCRIPTION
SYMBOL VALUE
VALUE VALUE
UNIT
REFERENU:MM7.10
NET DESIGN WIND PRESSURE (UPLIFT) P.". -02.1 73.4 -108.5 psf Figure 30.5.1, pi,346
N ET DESIGN WIND PRESSURE (DOWN) P..� 1 20.3 20.3 20.3psf Figure 30.5.1. IF, 346
NET DESIGN WIND PRESSURE (UP) PMw -50.94 438.81 -131.2 psf Calculation P„ew=AXKnXPmm
NET DESIGN WIND PRESSURE (DOWN) Pmdd.n 1 24.56 24.5624.56psf Calcination: Pda = A X K"X P_ue
DESCRIPTION SYMBOL VALUE VALUE VALUE
DEAD LOAD
D
SNOW LOAD
S
DESIGN WIND LOAD
W
ASO DESIGN LOAD(UPUFT)
DOWNFORCECSES
pdd.y.
DOWNFORCECASE2
pdµ,
DOWNFOROECASE3
Pd
0-131.29-99.37
H3
327.5621.42
DESIGN FARORS & CALCUTATONS FOR THE USE OF RT MINI TO ROOF TRUSS
DESCRIPTION SYMBOL VALUE VALUE VALUE
MODULEWIDTH
B
TOTAL DESIGN LOAD (UPLIFT)
P
TOTAL DESIGN LOAD(OOWNFORa)
P
DISTRIBUTED LOAD (UPLIFT)
w
DISTRIBUTED WAD(DOWNFORCE)
w
RAIL SPAN BETWEEN ANCHORS POINTS
L
POINT LOAD (UPLIFT)
R
POINT LOAD(DOWNFORCE)
R
L-FOOTOONNECTED BY LAG SCREW TO
Roof truss
Specific GmviW,
G
Min. Dia. of lag Screw, 1/4"
D
Pullout Value of
W
R of lag screws
Thread Length
Td
Design Pullout Value per Mount
Wr
SAFTEYFACTOR
SF
uP1,pr�lr WXs4urr.rl
3:28
3.28
3.28
737.13
-66.47
49.37
27.56
2756
2756
-60.90
.109.01
-16L97
45.20
45.20
45.20
4
4
2
-243.61
.436.05
.325.93
180.81
180.81
90A1
0.5
0.5
0.5
0.25
0.25
0.25
225
225
225
2
2
2
1.5
1.5
1.5
675
675
675
2.77
1.55
2.07
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IY
c.br B..YI.g TT /
G.Na Rewp•
❑ au.aiors � [ML
XUI,.L.INyX.}wd FM.
1w� LL1IDeai��Yd•I�ah Fa.e-a nan X.s�Ob�4 P.,.
UNIT
psf
Psf
psf
Pal
Calculation: P,,,=D,SORT(0.6)W(asd)
Pal
Wlculatlon: Pdeio,=I.0D.lDS
psf
Calculation: Pd,=1.OWLOW
psf
Calalatlaa P, ,=1.ODL0.755 .75W
UNIT
R
psf
Pot
PH
Calculation w=PB/2 •''""'!ae"a °"'0'
pif
WlMation:w=PB/24a 2"am'm
It
be
CAlculatlon:R=PUB/2*MWr 2'aaP-
Ibs
Calnrlatlom R=PLB/Z'P' ""x,a6 P--
Table 11.2A6 ND52005, page 68 (Southem Pine)
n
bs/In W=1800GV'DV4
n Table LZ, ND52005
W.=W•A of Up d
Calculation: SF=WVR (UPli0)
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