Framing A Shed Roof With A Valley

Use a framing square to help lay out the notch based on the slope of the roof.

Framing a shed roof with a valley.

Measure form the top of this line down the board to determine the line length or length of the rafter less the ridge. For our 4 x8 lean to example using a 2 4 rafter the depth of the birdsmouth is limited by the 1 3 depth of the rafter rule. In truth framing in the foundation and the walls adding doors and windows these are all relatively straightforward simple tasks. That is except for the crowning glory the shed roof.

Position the square at the end of the rafter board with the tongue on your left and facing away from you. The valley rafter is marked for a 12 in 17 pitch and then cut with a double bevel to fit into the ridge intersection. Add the length of the overhang beyond this mark and. For many people the idea of having to do the shed roof framing is a little bit on the scary side.

A 2 4 wall with a 2 6 rafter can be notched for a 4 seat. At the low end of the valley the subfascias of the two roofs are mitered with a block filling in the roof framing.