Hip Roof Jack Rafters

This calculator returns the first 16 jack rafters.
Hip roof jack rafters. Span for the main rafters measure from outside of wall to outside of wall. Rafter is called for only when framing a hip roof but a valley rafter is needed on both hip and gable roofs whenever roof planes intersect. The 7 12 pitch hip roof is framed with 2x6 common and jack rafters on 16 inch centers and with 2x8 hips and ridge. I use it with an adjustable stanley quick square and can cut the whole roof on the ground take all the timbers up and assemble the lot in one go.
When you create a hip roof in a timber frame there are different types of rafters used. Depending on the size of the roof most hip roofs will have 4 6 short jack rafters that are spaced out every 20 inches 51 cm between the hip rafters and the king common rafters. All the complicated trigonometry calculations are done for you and there s loads more in there too like diminishing jack measurements and hip rafter lengths and angles as well. 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.
Rick arnold frequent contributor to fine homebuilding and the journal of light construction presenter at jlc live the katz roadshow the remodeling show. Use the hip roof calculator for an easier way to get started. Select the following information by using the drop downs to enter values in feet and inches. Know that the basic skeleton for the roof has to be erected before any jack rafters can be installed.
The total rise of hip and valley rafters is. A jack rafter is a shortened com mon rafter that may be framed to a hip rafter a valley rafter or both. At the birdsmouth i supplied the 3 inch seat and for the rafter tail a 12 inch overhang with a 2 inch high subfascia plumb cut which dictated the level cut at the heel. Thus there are hip jack rafters and valley jack rafters.
The hip rafters in purple form the roofline and extend from the plate to the ridge. This calculator will help you estimate hip roof parameters including rafters and roof area person outline anton schedule 2011 08 29 17 53 20 one of users asked us to create calculator which will help him estimate hip roof parameters like rafter s lengths roof rise and roof area. 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. Measure the distance between the angled hip rafter and the top of the wall at 20 in 51 cm increments and cut jack rafters to fit.