Low Pitch Roof Rafters

To resist thrust the irc calls for a structural ridge required for any roof with a pitch less than 3 12 or for each pair of rafters to be securely connected to each other by a continuous ceiling joist r802 3 2006 irc.

Low pitch roof rafters.

Many roofing shingles do not allow applications onto roofs at this pitch. A 4 12 is a roof slope that rises by 4 inches for every 12 inches across. It is always better to have a large rafter rather than be concerned with a sagging roof. More commonly roll on membranes such that use heat to bond seams together is used as a roofing material.

After finding out your roof pitch angles you can use the calculator to perform the calculations for you instead of doing them manually. This horizontal load or thrust can be considerable especially on a low pitched roof. Visit the roof framing page for more information on cutting roof rafters and visit the roof pitch calculator for determining rafter lengths based on rise and run. Structures such as sheds or barns can be frames with rafters every 24 again make sure to consult local codes.

A low pitched roof is anything that is any roof with a pitch of 3 12 or less. This forms an angle of 18 5 between the horizontal section and the roof and creates a gentle incline that is seen as a midpoint between a low pitch and medium pitch roof.