How To Measure Roof Pitch Slope

Generally roof pitch is calculated from the same formula that describes a right triangle.

How to measure roof pitch slope.

Rafter rise run from the pythagorean theorem. A barge rafter at the side of the gable step 2 position a level against the underside of the rafter. Locate the level s 12 inch mark. The overhang of a rafter at the end of the roof.

Access one of the rafters then take the measurement this way. Measuring from the underside of the roof is usually the most accurate way to find the slope since there is no roofing material to make an uneven surface. You can use the following equations to find the length of the rafter and the slope. Step 1 access a rafter.

How to determine or calculate roof pitch or roof slope roof pitch calculator is determined by the number of inches it rises vertically for every 12 inches it extends horizontally. Use a level against the underside of the rafter you re measuring to get the most accurate value. This measurement is best done on a bare roof because curled up roofing shingles will impair your measurement. Rise run pitch where pitch is expressed in percent.

The picture below shows the pitch of a 7 12 roof slope meaning that for 12 of horizontal measurement roof run the vertical measurement roof rise is 7. How to calculate roof pitch. How to obtain roof pitch or slope by using the rafter tables on a framing square measuring the roof slope pitch or rise and run is easy if you ve got a tape measure and more accurate still if you ve also got a level on hand. Also referred to as roof slope or roof slant so what does the 7 12 in the example to the right mean.

But did you know that simple data already printed on your framing square can give key roof slope and rafter data.