In this diy guide you will learn how to install a roofing joist or rafter that includes how to work out the pitch of a roof cut a ridge or plumb cut at the correct angle work out the correct length of joist you need and the exact location for a birds mouth joint how to correctly cut a birds.
Plumb cut roofing.
Birdsmouth which consists of two cuts a horizontal seat cut and a vertical shoulder cut.
Designing the right roof rake.
So if your roof is a 45 degree angle that is for every 12 along the horizontal run it rises 12 it s a 12 12 pitch.
Select a roof pitch.
Here the birdsmouth plumb is 76 37 inches.
The traditional method has been rise inches 12 run inches.
The results are automatically fired as soon as any of the values are entered or altered.
Roof pitch is measured in a rise to run ratio with the vertical rise always shown first.
For two cut plumb and two cut square specify a value for fascia depth between zero and the thickness of the roof.
When framing a gable or hip roof the final step is cutting the rafter tails for fascia board.
Locate these rafter terms in the illustration below.
How to plumb cut rafter tails.
After creating a roof change the style of the eaves by specifying the rafter cut.
Read more about roof design.
Plumb cut eaves are perpendicular to the ground while square cut eaves are perpendicular to the angle of the roof.
Architectural elements to use and avoid.
Plumb cut definition is a cut in a vertical plane.
On the properties palette for rafter cut select plumb cut two cut plumb or two cut square.
In the drawing area select the roof.
Depending on the size of your structure you will need to cut several or many more.
If it rises onlyread more.
At this point you ve cut 1 roof rafter.
Marianne cusato is the author of get your house right.
Birdsmouth plumb if you study the diagram carefully you will see that there is an indentation in the roof rafter where it meets the exterior wall of the building.
Tail cut which may be cut plumb or square depending on how the eaves are detailed.
Some architectural designs call for plumb or vertical cuts as opposed.
Determine a thickness for the ridge and use the drop down to select it.
All roof rafters should be identical so follow the same steps to measure the plumb cut tail cut and birdsmouth cut.
The length of the rafter is given from the long point of the ridge cut at the top down along the top edge the board to the same plumb cut on the rafter s notch.
Birdsmouth joint how to cut a birdsmouth and how to cut and install roofing rafters and joists.
The top cut face of a rafter that is designed to butt vertically against a ridgeboard.
Venting a traditional eave.
Plumb cut typically called the ridge cut at the top end of the rafter.