Calculate the length of common rafters with this free and easy online tool by entering a dimension for the roof width selecting a pitch for the roof and the thickness of the ridge.
How to find roof rafters.
The roof on this shed is a 4 in 12 slope which makes it a 18 and.
Height of the scaffold.
The rise of the rafter.
The run of the rafter.
The results are automatically fired.
Before you cut your boards you ll need to measure the width of your building and calculate the exact length of each rafter.
Rafters are evenly spaced so knowing how far apart they are gives you the ability to find the rafters while on the roof.
Rise and run means that a 6 12 pitch roof has 6 of rise vertical for each foot of run horizontal.
The first step in building the roof rafters is to cut one rafter board to length with the ends angled properly and then to mark and cut the birds mouth and seat on the rafter.
If you re framing a gable roof on a new house or building a shed or even a doghouse with a gable roof you ll need to cut a number of roof rafters.
When constructing roof rafters always cut a pair first and try them to check they fit.
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.
The length of the rafter.
Unlike rafters for flat roofs rafters for pitched gable and hip roofs rise at an angle from the outside walls and meet at a ridge.
If you add an eaves overhang dimension then the amount the rafter sticks passed the wall will be added to the rafter length.
Once happy use one of those as a pattern to cut the rest with.
Angle the angle of a roof is the same as the roof s slope except instead of being.
Includes result for hip valley factor slope factor and the roof slope in degrees.
Calculate the length of a rafter from the roof slope ratio of inches per foot and a building width measurement.
The picture below shows how these cuts are used to create the angles that help the timber form the shape of an angled roof rafter.
Given here are the formulae to calculate the length of a shed roof rafter to make your roofings stronger and look beautiful.
Always use the same rafter as the pattern to ensure accuracy.
Slope the slope of a roof is represented as x 12 where x is the number of inches in rise for every 12 inches of run this is very useful information for many purposes especially for roof framing the slope sometimes called pitch is calibrated on speed squares.
As a do it yourself builder you can expand your knowledge of basic roof construction by calculating the length of the rafters for a particular roof section or room.
Roof pitch calculator results explained.
This marks the center of the first rafter.
Transfer the measurements to the roof.
While making roofing for your house with the roof rafters it is important to know the rafter length to make the roof seat perfectly on the rafter.
