Select build roof build roof from the menu and in the build roof dialog specify the pitch framing and any other attributes that you will need for the cricket.
Framing and roof crickets.
This also makes it easier.
Here the build roof dialog is being used to set the defaults for manually drawn roof planes.
Do not check build roof planes.
In this example a pitch of 12 12 and 1 1 2 x 5 1 2 rafters are specified.
2x8 sleepers should be nailed to the roof surface to pick up the ends of the rafters.
This is the number which we will use to lay out our rafter for the cricket.
The cricket or saddle basically rests on top of the house roof to visually extend the porch roof gracefully into the house roof.
This beam will provide the backbone for the cricket or saddle.
You will need to use compound miter cuts for the cricket rafters.
Install a waterproof membrane over the cricket sides and edges fastened to the cricket with a construction stapler.
Ok so a four foot wide chimney has a span of 4 foot and half of that is the run which is 2 foot.