How To Build Hip Roof With Unequal Wall Lengths

How to use the hip roof framing calculator.

How to build hip roof with unequal wall lengths.

Measure distance a along the unit run and mark. Repeat the same procedure on the side of the hip that faces the secondary roof using the hip pitch for that roof and measuring distance b. The hip roof framing calculator returns the value of the main rafter the side rafter the length of the hip the height of the knee wall and the lengths of the jack rafters. Hip backing angle 15 4 for a good straight fascia add an extra inch or 2 to the tails of all your rafters total length.

The hip end jacks tab displays a dimensioned side view and top view of the hip roof jack rafters for the hip end side of the hip rafter on an irregular hip roof. The first step in the process of erecting the hip roof is to get the ridge beam into place at the top of the roof. Place your square on the side of the hip rafter that will face the main roof using the hip pitch for that roof 8 155 8. To get results you need to provide roof base dimensions length and width and roof pitch we assume it is identical for all sides.

This is the line of backing. Attach 4 6 centering rafters and lift the ridge beam into place. The backing of hips on roofs of uneven pitches while the amount to be removed on each side of the hip will vary is determined by the principles developed in sec. That is where the seat cut should be made.

Lengths of hip and valley jacks are determined as in. Mark the length of the hip measuring down from the longest point of the plumb cut. The drawings are representative of all of the hip end side jack rafters and do not include the overall lengths which are available on the layout tab. The amount to be removed from each side must be separately determined according to the angle the hip makes with the plate.

After they re up you can snap a line to mark and trim the tails in a nice straight line to make up for any ridge warp or marking cutting and fixing errors. Then mark another plumb cut 25mm over which denotes where the hip would touch the wall plate if it wasn t for the gap. The typical gable roof diagram above shows the r length measured from the outside wall to the middle of the ridge beam the rafter section diagram below typical of a shed or patio cover roof shows the r length measured from the outside wall to the outside face of the ridge beam either one is acceptable depending on which type of roof you are building but if you are using the. Then measure down that plumb cut the same distance as the common rafter s height above plate.

All formulae are below the calculator.