1 4 12 Roof Pitch

Identify the rise and run.

1 4 12 roof pitch. If this isn t practical then perform the same measurement on the underside of the roof. So use the 12 inch level as a constant run and 18 inch ruler as a variable rise. If a roof rises 1 in a length of 12 this is 1 12 roof pitch. The 12 inch run is considered standard in roof pitch or angle terminologies.

On blue prints architects engineers usually display the pitch of a roof in the format shown on. Thermoplastic single ply membrane roofs must have a design roof slope of 1 4 12 or greater 2 slope. This means for every 12 horizontal units the roof must rise a minimum of one fourth vertical unit. Most roof s have a pitch in the 4 12 to 9 12 range.

A pitch over 9 12 is considered a. In the usa the range of standard pitches is anywhere between 4 12 and 9 12. The rise will be equal to the amount of the incline within the given distance or the run that measures 12 inches. In the uk the typical house has a pitch between 40 50 although 45 should be avoided.

Roof pitch varies depending on culture climate style and available materials.