Hip Roof Framing Purlins

Hip roofs have hip rafters which are oriented diagonally to the ridge and outside walls.

Hip roof framing purlins.

Roof framing geometry kernel rafter lengths roof ratio multiplier. Stabilization typically involves installation of a purlin system. The common rafter length can be calculated by the roof ratio length per 12 of run. Hip rafter ratio length multiplier hrrlm 18 12 1 5 common rafter length multiplier crlm 13 4164 12 1 11803.

Photo above is from a jwk inspections framing pre drwall inspection in the san antonio south teaxas area showing the actual roof framing componenents. Now outline the biggest rectangle inside the building layout. Here roofs are constructed with an angle of 90 degrees. Now draw the centerlines for all rectangles that are formed inside.

All angles can be found on the chappell univer. This series covers roof framing roofing materials the attic and the conditions that affect the roofing materials and components including wind and hail. Divide the rafter length by 12 of run to calculate the roof ratio multiplier. Hip and valley roof framing is no so complex as compared to hip roof framing procedures.

Purlins are not required or needed unless rafters are overspanned and then the purlins serve as support to prevent roof sag deflection due to the overspanned and or undersized rafters. First of all you need to design the layout of building. Porch roof extensions for hip roof porch extensions from an existing building wall you can use half the calculator results.