Gambrel Roof Angles

The purlin method calculates cuts that bisect the angles at the roof joints.

Gambrel roof angles. Gambrel roof a gambrel or barn style roof is simply a gable roof with a change in slope partway up the roof. A gable roof has only two rafter or truss chord angles a top cut at the peak and a bottom cut at the walls. You will need to make 22 5 degree angle cuts on the rafter joist ends that mate up to the top plate or header. If you plan on building and installing your own gambrel roof you ll have to draw out plans first to determine the proper dimensions.

Check overhang to calculate rafter overhang equal to the lower level cut at the full rafter depth. Since the sum of the three angles in a gambrel roof is 180 degrees the angles you will need are as follows. A gambrel style is often called a barn roof. 45 degrees where the joists meet up with the top plate or header and 90 where the joists meet in the middle at the ridge board.

A gambrel or gambrel roof is a usually symmetrical two sided roof with two slopes on each side. Gambrel roofs are symmetrical with two slopes on each side of the roof. Its double or sometimes triple slopes on each side of a peak provide more space inside the roof which is attractive to homeowners too. Besides its unique appearance a gambrel roof also serves to maximize the usable floor space in the attic area.

Move slider or directly enter angle to alter sweep angle of lower rafters and change the shape.