To create the desired cut you can use an in place void family on the high roof.
Revit birdmouth cut roof.
This is relatively simple.
Make one rafter that has the bird s mouth cut in place and extends out past that for your roof overhang test fit it in place and mark it pat for pattern rafter to use in cutting its sisters.
The width of the 2x4 used to frame the outer wall measures 3 5 inches 8 9 cm and the outside sheathing measures 1 2 inch 1 3 cm.
When you placed fascia and set the rafter cut of the roof to two cut plumb or two cut square in the roof properties only the slope defining edge was affected.
You can cut openings in the faces of these elements or you can select the entire element to make a vertical cut.
Tutorial on roof construction modeling in revit.
The birdsmouth joint also called the birds beak cut or birds beak joint is a small triangular shaped cut out at the base of a roofing joist that allows the joist to sit nicely on top of the wall plate top of the wall before the roof starts.
Measure the full width of the outside wall.
Solution by design only roof edges that are slope defining are affected by the rafter cut.
For most buildings the birdsmouth cut is 4 inches 10 cm deep.
Determine the depth of the birdsmouth cut.
Click by face or vertical.
Draw a line at right angles to the bird s mouth plumb cut starting 3 inches up from the bottom of the rafter but no more than half the thickness of the rafter.
Use a square placing one side against the plumb cut line.
You created a roof that has only one slope defining side.
In my photo above the green rafter line length is from the plumb cut face or ridge board face to the plumb cut face of the bird s mouth notch.
Architecture tabopening panel structure tabopening panel use the by face option when you want the.