Hip Roof Framing Purlins

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.

Hip roof framing purlins.

Now outline the biggest rectangle inside the building layout. Enter the extension wall length into wall length and double the extension wall width then minus ridge thickness into the wall width entries. Hip rafter ratio length multiplier hrrlm 18 12 1 5 common rafter length multiplier crlm 13 4164 12 1 11803. Hip roofs have hip rafters which are oriented diagonally to the ridge and outside walls.

Minus ridge thickness to allow for ridge becoming pole plate roof peak will be slightly higher ridge thick must be same. Porch roof extensions for hip roof porch extensions from an existing building wall you can use half the calculator results. This series covers roof framing roofing materials the attic and the conditions that affect the roofing materials and components including wind and hail. Hip rafters are.

First of all you need to design the layout of building. Photo above is from a jwk inspections framing pre drwall inspection in the san antonio south teaxas area showing the actual roof framing componenents. All angles can be found on the chappell univer. Here roofs are constructed with an angle of 90 degrees.

Divide the rafter length by 12 of run to calculate the roof ratio multiplier. Now draw the centerlines for all rectangles that are formed inside. The common rafter length can be calculated by the roof ratio length per 12 of run.