Surface area of sloped roof from arial photo

Postby stevex710 » Thu Aug 02, 2007 1:50 pm

Is it possible to calculate an esimate value for the surface area of a roof.
roof in question is a hip roof - 2 triangles at either end of roof.

i know the length and width of the roof but because of the slope wouldnt the surface area of the roof be larger?

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Postby Perry525 » Tue Aug 14, 2007 8:08 pm

Yes it is bigger.
Measure the roof angle in the vertical plane, transfer onto graph paper, measure and there's your answer.
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Postby youasked » Fri May 08, 2009 11:53 am

If you have concrete Marley type tiles, a general rule is: Count the tiles from gutter to ridge. Divide by three (3 tiles per meter) that is your height,
Measure the triangle hip, half way along the gutter (from point of hip) to end of gutter. (does that make sense?) (Or you can measure the whole width and half it). Multiply the height x the half width and that give you the size.

Example: 15 tiles from gutter to top of hip. = 5 mtrs.
12 mtrs width (divided by 2 = 6) = 6 mtrs
6x5= 30 mtrs
If detatched house then there are two ends = 60 mtrs.

The front can be done the same way by divideing the roof into 2 x triangles and one rectangle.

NB: as the traingles in all cases are right angled, you only have to calculate one on each facet, as the other is the same. " 2 X triangles make a square (or rectangle). send ME A JPEG AND i WILL DO IT FOR YOU.
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