How Steep Should A Roof Be

You can also divide the rise over run multiply by 100 and get a percentage.

How steep should a roof be. The exact roof slope in degrees is given by the arctangent. A 4 12 pitch is around 18 5 degrees but not exactly. If a roof increases in height by three inches for every foot of horizontal run it is considered to have a 3 in 12 pitch or just a 3 pitch the primary purpose of pitching a roof is to redirect water and snow. Definitions vary on when a roof is considered pitched.

2 12 4 12 conventional slope roof. However in general terms low slope roofs commercial roofs are those below 2 12 or 3 12 while steep slope roofing would consists of roof pitches above either 2 12 or 3 12 and higher. A flat roof would have a 2 12 pitch while the average roof pitch would be between 4 12 and 9 12. Thus a 4 12 pitch would be a 33 slope.

The slope of a roof has an effect on the interior volume of a building the drainage. 9 12 20 12 steep slope. Roof slope is a very important aspect and it is considered the primary factor in roof design. For most home styles roof pitches fall in a range 4 12 a moderate slope up to 8 12 fairly steep.

A ratio is the most common way of expressing roof pitch or roof slope but degrees are also possible. Any pitch higher than 9 12 is considered a steep pitch. Examples of extreme slopes range from 1 4 12 almost flat to 12 12 sloping down at a perfect 45 degree angle.