Gambrel Roof Rafter Angles

A gambrel or barn style roof is simply a gable roof with a change in slope partway up the roof.

Gambrel roof rafter angles.

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 has four angles at the peak at the wall and where the two rafters or truss chords connect. This gambrel roof confines to a semicircle and starts as the top half of an equal sided octagon.

Move slider or directly enter angle to alter sweep angle of lower rafters and change the shape. To calculate a gambrel roof select gambrel roof from the roof type dropdown list or click on the appropriate toolbar button to calculate a. A gable roof has only two rafter or truss chord angles a top cut at the peak and a bottom cut at the walls. Its double or sometimes triple slopes on each side of a peak provide more space inside the roof which is attractive to homeowners too.

You will need to make 22 5 degree angle cuts on the rafter joist ends that mate up to the top plate or header. Since the sum of the three angles in a gambrel roof is 180 degrees the angles you will need are as follows. Move slider or directly enter angle to alter sweep angle of lower rafters and change the shape. Gambrel roofs are symmetrical with two slopes on each side of the roof.

Online calculator produces an accurate calculation of the rafters online calculates the sizes of rafters for the roof. A gambrel roof is a popular roof style on many contemporary barns and sheds. Besides its unique appearance a gambrel roof also serves to maximize the usable floor space in the attic area. If you plan on building and installing your own gambrel roof you ll have to draw out plans first to determine the proper dimensions.

The length of rafters length overhang the angle of the saw cut the distance to drinking. Check overhang to calculate rafter overhang equal to the lower level cut at the full rafter depth. Gambrel roof framing geometry calculator inch this gambrel roof fits in a semicircle and starts as the top half of an equal sided octagon.