If you re planning on building a gable roof with a pitch of 4 12 for a shed that s 200 inches 510 cm wide your rafter boards would need to be 105 3 inches 267 cm long on each side.
Shed roof dimensions.
The advantages to sourcing this product through tuff shed include quicker turnaround time delivery of the units fully assembled and the ability to purchase in single unit quantities.
This means that for every 12 horizontal run you must have at least 3 of rise.
Don t forget to cut the ends of each board to the appropriate angle to allow them to fit together at the peak.
Rafter is the beam supporting the building.
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.
To calculate a shed roof select shed from the roof type dropdown list or click on the corresponding button on the toolbar to calculate a shed roof.
As a general rule roofs that have a high human occupancy rate should be framed with rafters every 16 structures such as sheds or barns can be frames with rafters every 24 again make sure to consult local codes.
Anything less than this will ultimately result in a roof that leaks if you plan on putting shingles on it.
Since the ridge of our gambrel roof will run the length of the shed down the center that leaves us with about 4 horizontal feet from the ridge to the outside edge of the shed.
Now let s say you want to build an 8 10 shed with a gable roof.
That gives us rise over run of 2 4.
You want the ridge of the gable to be 2 feet.
A useful shed roof rafter calculator to calculate the rafter length for the given dimensions of the roof of the building or a structure.
8 8 8 12 8 16 and 8 20 sizes available.