How To Figure Out Roof Valley Angle

Calculate the length of a rafter from the roof slope ratio of inches per foot and a building width measurement.

How to figure out roof valley angle.

Divide the rise by the run the run is 12. The hip and valley factor varies according to the slope of the roof as shown in the table below. Hopper valley angle calculation inputs internal angle wall a to vertical α1. Check all your measurements twice.

So we have two equations. To calculate what r and a are note that rcos q a r cosq cosa r sinq sina r cosa cosq r sina sinq by the above identity. First enter the value of the rise and choose the unit of measurement from the drop down menu. Then enter the value of the run and choose the unit of measurement from the drop down menu.

So we need to set rcosa a and rsina b to make this equal to acosq bsinq. The calculations will be. Simply enter the roof pitches and press the calculate button the calculator will supply the direction and precise angles for the framing members as well as the connectors. Rcosa a 1 rsina b 2 we can find a by dividing 2 by 1.

Convert measurements in feet and inches into decimal values before determining the roof angle. Degrees internal angle wall b to vertical α2. Here are the steps to follow for the roof angle calculator. This slope and skew calculator makes it easy by performing all of the necessary trigonometry for each hanger condition in the roof.

Results internal valley angle to vertical α3 degrees external angle to horizontal α4 degrees. The preview window displays a plan view of the valley roof. Includes result for hip valley factor slope factor and the roof slope in degrees. Degrees note type in respective value inside of coloured cell above then click outside cell to enter.

To calculate a valley roof select valley from the roof type dropdown list or click on the the corresponding button on the toolbar to calculate a valley roof. If you use the wrong dimensions you will find the wrong angle.