Calculate a roof's pitch by measuring the rise versus the run, with the pitch being however many inches the roof rises for a 12-inch run. Layout a shallow roof at a 3- or 4-inch pitch or a standard roof at an 8- or 9-inch pitch, with instructions from an experienced builder in this free video on carpentry.
3 and 12, 6 and 12, 9 and 12, 18 and 12 all these are the ways that we are talking about roof pitches. I am Robert Markey and I've been doing construction for many years and we are going to talk about how to determine the pitch of the roof. Basically a roof pitch is the amount of rise over the horizontal distance and is a factor of 12. In other words for every 12 inches that we go over how much do we go up. So if we have a level here, we go over 12 inches and we go up 2 and 3/4 inches so the pitch of this roof would be at 2 and 3/4 in 12 pitch. Very shallow roof. Your standard roofs tend to be 8 and 12, 9 and 12. The other way you can do this is we could measure the hole distance of the roof, measure the height up at the peak of the roof and then divide it all by 12 so we are basically still getting the factor of how much rise there is per 12 inches of run or how many feet rise there is of 12 inches of run, however you want to look at it so that basically is the idea of roof pitch. I'm Robert Markey and we've been talking about determining the pitch of the roof.