1997 ubc wind loads for components
 

1997 ubc wind loads for components
has anyone ever compared the asce 7-02 component wind loads to the 1997 ubc wind loads for components? we started reviewing shop drawings for a project for claddding and girts for a transfer tower using the asce spec. and then found out we had to use the ubc. my calcs. show an increase in wind load of 50%. they are saying i am wrong but at this time won't review my calculations. it is costing the fabricator money.
it is exposure c at 105' high, 90 mph, 68 sf. area of cladding for the girt loading.
thanks
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here's what i get:
ubc 97
wind - 90 mph
exp c
height - 105'
area 68 sf
qs = 20.8 psf
wall elements not in areas of discontinuity - enclosed and unenclosed buildings
area = 10 sf: +/- 40.6 psf
area = 100 sf: +/- 30.4 psf
wall elements not in areas of discontinuity - partially enclosed buildings
area = 10 sf: - 54.1 psf
area = 100 sf: - 43.9 psf
wall elements in areas of discontinuity
area = 10 sf: + 40.6 psf and -50.7 psf
area = 100 sf: + 30.4 psf and -40.6 psf

make sure you are using the correct/converted wind speeds between the two methods... then i believe they should be fairly close for the resultant pressures (not 50% difference).
ubc uses 'fastest mile' wind speed
asce uses '3 second gust' wind speed
90mph(3 second gust) converts to approximately a 76mph(fastest mile) wind speed.
or
90mph(fastest mile) converts to approximately a 105mph(3 second gust) wind speed.
jae wamre thanks. can you take a look at the following:
p=ce*cq*qs*iw
ce=1.62
iw=1.15
qs=20.8
wall elements not in areas of discontinuity - enclosed and unenclosed buildings
a=68sf. cq:1.01
p=39.1 psf- inward & outward
roof elements not in areas of discontinuity - enclosed and unenclosed buildings
cq=1.11
p=43.04 outward
wall elements in areas of discontinuity
cq=1.01 inward
cq=1.31 outward
p=39.1 psf inward
p= 50.8 psf outward
roof elements in areas of discontinuity - enclosed and unenclosed buildings
cq=1.78
p=69.0 psf outward