How To Determine Roof Slope Or Pitch
The height of your roof, based on its width is known as the slope or pitch of the roof. This number is expressed as a ratio of height versus width for every 12-inches. If a roof rises 7-inches for every 12 inches in width it is said to have a slope or pitch of 7-inches, as shown in Figure 1. It can also be expressed as 7 in 12.
Figure 1 - Roof pitch or slope
If you are planning to purchase new roofing material it is important to know the slope or pitch of the roof because certain roofing materials are designed for a minimum and/or maximum roof slope or pitch.
How To Measure Roof Slope Or Pitch:
Mark a straight level at a point 12-inches from the end. Place the end of the level against the roof and adjust it so that the bubble is level. Using a tape measure or ruler, measure the height from the roof to the point on the 12-inch point that you have marked on the level. This will provide you with the slope number of your roof, as shown in Figure 2.
Figure 2 - Measuring roof pitch or slope
Table 1 shows the definitions of roof pitch or slope and walking ease.
| Table 1 - Roof Slope/Pitch Definition | ||
Roof Type |
Slope or Pitch |
Walk-Ability |
Flat |
0 - 1 |
no problem |
Low |
2 - 3 |
easy |
Medium |
4 - 6 |
comfortable |
Steep |
+6 |
difficult |