How to Calculate Roof Pitch

Q. I need to submit a claim form to get reimbursment on shingles that are in need of replacement and on the claim form, they ask for the roof pitch. I looked all over on my original blue prints of my 1993 Artcraft 16x80 mobile home and can't find this information. Can somebody please tell me how to calculate roof pitch, or maybe somebody already knows what the pitch is on this type of mobile home. Seems to me that my roof is the same pitch as any or most mobile homes of this style.


A. Roof pitch (slope) tells you how many inches the roof rises for every 12 inches it runs. Example, 7/12 pitch means that the roof rises 7" for every 12" it runs.

One way to measure is to mark a level at 12" from the top of the roof, hold it perfectly level and measure from the roof surface to your 12" mark. This will give you the rise. Be careful with this method as a roof with many layers of shingles, or any type of roofing that is irregular can give you less than precise measurement.

Measuring from the bottom of the rafters, the procedure to calculate roof pitch is the same. This method tends to be more accurate because no layers of roofing are involved. To use this method there are three possible places to take your measurements. 1. The underside of a barge rafter on a gable end. 2. The underside of a rafter on a overhang at the bottom of the roof 3. The underside of a rafter in the attic.

Info courtesy of Community Member twelvepole. Visit our Community Forums for more answers to your home improvement questions.