Formula?
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Jed
If you are given the measurement of a pitched roof, but the take off was performed on the roof, is there a formula that you can apply to give you a footprint of the measurements? ie, the gable end measures say, 20' up one rake, and 20' down the other side, how can you calculate the length of the supporting wall at ground level from the drawing?
Robby the Roofer
L x W x pitch factor = Area ....of roof plane. Now how do you get your gable ends for rake metal? W x pitch factor = L...That will get you up and over the other side for measurements for gable trim. How do you get valley measurements for valley metal? Most people will guestimate, but to be acurate...I will pull out my "Full Lenth Roof Framer" bood by A.F.J. Riechers.
Jed
pgriz Said: Going from horizontal measurement to slope, you multiply the horizontal by the slope factor to get the on-slope measurement. If youve got the on-slope measurement, you divide by the slope factor to get the horizontal measurement. Or did I misunderstand your question?No, you understood me Paul but what I do for a take off is square off the roof from the drawing, then use the pitch table (4/12 multiply by 1.054.... 5/12 multiply by 1.083...etc) to account for the pitch. So the degree of the slope is not something that is isolated in the equation. You are right though I could do it that way. I just wondered if it was something everbody does and I just missed the memo.
OLE Willie
Well, you could just measure the wall when you come down from the roof! lol
pgriz
Going from horizontal measurement to slope, you multiply the horizontal by the slope factor to get the on-slope measurement. If you've got the on-slope measurement, you divide by the slope factor to get the horizontal measurement. Or did I misunderstand your question?
tico
I use A construction master.you can put in the pitch,say it's 6" pitch,you put in 6 in.pitch,your diagonal is 20 ft.you punch 20 feet diagonal,then just hit run,you then have 17 ft.10 in.11/16,which you double = 35 ft. 9 in.5/16 if you've got A hip line you can hit hip/v and it'll tell you that no.which is 26 ft. 10 in.
I used to measure for the car and shoe salesman.I do it from the ground. you measure it out,know the pitch(which any roofer can get right within 1 point up or down).and on the grand scheme of things only changes it by inches.when you work with adjusters they lay tape in the gutter and give A few anyways for the most part.
