Framing A Shed Roof With A Valley

On the common rafters the plumb cut is marked with a framing square for a 12 in 12 pitch 45 and cut square i e no bevel.

Framing a shed roof with a valley.

Use a framing square to help lay out the notch based on the slope of the roof. 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. Sheathing blocking is added along the valley and the sheathing pieced in for both roof planes. Position the square at the end of the rafter board with the tongue on your left and facing away from you.

To transition the eaves the horizontal fascia extends to the last rafter tail and a vertical return finishes the transition. At the low end of the valley the subfascias of the two roofs are mitered with a block filling in the roof framing. Add the length of the overhang beyond this mark and. Measure form the top of this line down the board to determine the line length or length of the rafter less the ridge.

The valley rafter is marked for a 12 in 17 pitch and then cut with a double bevel to fit into the ridge intersection. In truth framing in the foundation and the walls adding doors and windows these are all relatively straightforward simple tasks.