Nail along the edges of the osb or plywood driving the nails into the rafters every 8 inches 20 cm with 8d common nails.
Framing a gambrel roof overhang.
A gambrel roof overhangs the façade whereas a mansard normally does not.
This serves the purpose of the eave and creates shade and protection against nature s elements.
Start with the top corners of the roof first.
For gabled roofs the roof rafters extending beyond the wall caps creating an angled roof overhang on the eaves.
A rake on the gable end of the roof can be created with the construction of additional roof framing.
Frame roof no overhang.
Attach the components to the gambrel ends and secure them to the framing with 3 1 2 galvanized screws after drilling pilot holes.
Installing the roofing sheets.
As you can notice in the image you need to use regular trusses and to install 7 blockings as to get a 10 overhang.
Shed framed with gambrel trusses building a gambrel shed truss when you are designing your shed roof whether it be a gambrel gable or saltbox you should never have any roof pitch less than a 3 12.
Place the osb or plywood on the top portion of the rafters and make sure that the edges run flush.
Raise and attach the walls.
The cross section of a gambrel roof is similar to that of a mansard roof but a gambrel has vertical gable ends instead of being hipped at the four corners of the building.
Due to the steeper angle of gable roof the maximum width of the eaves is narrower than other shed styles.
Build gable roof trusses 3 12 pitch.
Nail osb or plywood onto the rafters to enclose the roof.
Build gable roof trusses 6 12 12 12 pitch.
To create eaves on your barn style roof you can use a rafter tail.
This means that for every 12 horizontal run you must have at least 3 of rise.