How To Frame A Roof With A 12 12 Pitch

Trace the lines for the plumb cut and the level cut for the eave from the vertical and horizontal edges of the framing square.

How to frame a roof with a 12 12 pitch.

Flat roofs are great in climates with little rain but if you have a pitched roof you ll have the advantage of water draining away more easily. This will the first point of the rafter measurement line. You can then use the square to transfer the angle for the cut to the lumber. This measurement is best done on a bare roof because curled up roofing shingles will impair your measurement.

In the united states a run of 12 inches 1 foot is used and pitch is measured as the rise of the roof over 12 inches. The picture below shows the pitch of a 7 12 roof slope meaning that for 12 of horizontal measurement roof run the vertical measurement roof rise is 7. It is often compared to slope but is not exactly the same. But here it will be different since the hip rafter doesn t lie at 45 degrees to the commons.

Lay a framing square flat on the board near one end so that the horizontal blade aligns with the bottom edge of the board at 12 inches and the vertical blade is aligned at the roof pitch. Simply adjust the square to the desired pitch and lock in place with the knurled knob. Whatever your choice make sure to take the regional climate into consideration. For instance a 7 12 roof pitch means that the roof rises 7 inches for every 12 horizontal inches.

The minimum roof pitch is 1 8 inch rise per foot of span. Measure down y height from the long point of the rafter cut and make a mark. For example you may want a steep pitched roof or perhaps a flat one. Roof framing rafter layout.

Outside of the u s a degree angle is typically used. The pivot square can be set to any whole number pitch from 1 12 to 12 12. From one end of the rafter material using a speed square or framing square mark an x in 12 angle on the rafter and cut it. On the body of the square the longer side input the 12 and input the 7 on the tongue the shorter side of the square by lining up the stair gauges at the corresponding point on the square.

Input the pitch of the roof that you calculated above we ll use 7 12 for reference throughout on the framing square. In a hip roof with equal pitches the unit run of a hip or valley rafter is 17 inches for every 12 inches of run in the main roof.