Roof Pitch – Learn How To Measure And Calculate Roof Slope

Roof Pitch Multiplier Table

Roof pitch multipliers are basically a result of calculating the hypotenuse using the Pythagorean theorem. We provide this table for you to save time and not do the math. If you want, you can still verify these numbers yourself. To apply the roof pitch multiplier, just take the length of your gable side, and multiply it by the number corresponding to your roof’s pitch. This will give you the length of your gables (divided by two sides).

You can also use our handy Roof Pitch Calculator to quickly get your measurement by entering roof dimensions (gable side) and roof rise (distance between the base and the peak of the roof). This calculator will also provide roof size and the approximate cost to install an asphalt shingles roof.

Roof Pitch Multipliers:

What Is Roof Pitch?

Roof pitch is a concept used by contractors, architects and other building professionals to identify the slope or steepness of a roof. It is measured in inches or units, using a 12 base or run of the roof, compared to its rise. Using roof pitch greatly simplifies the estimating process, ordering materials and choosing the right product for each installation.

Pitch is similar to using degrees as a measure of the roof slope, and can be easily converted back and forth. However, it is much more convenient for contractors, builders, architects and roofing materials suppliers to use pitch instead of degrees, which makes the whole process of building a house and installing a roof much simpler.

The concept of pitch as a measure of roof slope is mostly used in the United States, UK, and in the former British colonies. The reason for this is that the main measuring units in these countries are inches, feet, yards, etc.

To explain it differently, think of the roof slope rising X number of inches for each 12 inches of horizontal run.

Why Do You Need To Know The Roof Pitch?

Roof pitch, converted into pitch multipliers, helps contractors / estimators measure the roof size and to estimate prices accurately. Estimators or homeowners are often not able to climb up on the roof or it is too steep or high up, and it is dangerous to measure sloped roof runs, such as the length of the gable from the roof. In this case, the pitch is used to get an accurate estimate of the real roof size, without actually getting on to the roof.

By knowing your roof’s pitch, you can also easily compare prices from different roofing contractors, as well as know how much the contractor is charging per square of roofing.

Read part 2 of this guide: How To Calculate Roof Pitch