How To Figure Rafter Length On A Hip Roof

Rise and run means that a 6 12 pitch roof has 6 of rise vertical for each foot of run horizontal.

How to figure rafter length on a hip roof.

Calculate the length of a rafter from the roof slope ratio of inches per foot and a building width measurement. Easy rafters does not calculate a complete four sided hip roof but rather calculates the common hip and jack rafters for one end of a hip roof. Select the following information by using the drop downs to enter values in feet and inches. Our roof rafter calculator tools are handy for calculating the number of rafters needed rafter length calculator lineal feet of rafter board feed in ridge and sub facia and the total board feet in the roof.

If you add an eaves overhang dimension then the amount the rafter sticks passed the wall will be added to the rafter length. How to calculate rafter lengths. The run of the roof in this example is 12 5 feet and the angle of the roof is 23 degrees so the length of a common rafter is 12 5 cosine 23 degrees 13 6 feet. 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.

Each common rafter span is calculated by subtracting the thickness of the ridge from the total span then dividing the answer by two. Typically this is shown on the roof construction plan. You ll also need to look for a hip roof design calculator to let you work out the height and the overall format of the design ensuring that your calculations are going to allow for the type of design that you were hoping for in the first place. Total span ridge 2 individual rafter span.

The other thing you ll need is the roof pitch angle. You might need a long tape measure to get the span then. They must must be on the same level. Take the square root of the result from step 6 to obtain the length of the hip rafter.

Rafter length using angle v r 2cos a rafter length using pitch v r 2 sqrt 1 p 2 where v overhang r roof span p pitch use our online rafter length calculator to quickly compute the length of the shed roof rafter by entering the measurements of overhead length of roof span pitch or angle. Determine the pitch of the roof which is the angle that rafters rise from the outside walls to the ridge. Span for the main rafters measure from outside of wall to outside of wall. To calculate a hip roof select hip from the roof type dropdown list or click on the corresponding button on the toolbar to calculate a hip roof.

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.