Use Roof Pitch To Cut Rafter Tails

How to measure or figure rafter length and mark and cut them accurately.

Use roof pitch to cut rafter tails. Nail these pieces starting at one end of the roof butting each piece flush to the one before. Cut 1 by 6 inch lumber to fit along the ends of the rafters from one end of the roof to the other. On the front of the roof edges the original roof deck sheathing was cut back flush with the wall and the fully adhered membrane folded down around the rafter tails to catch the wall water control layer and air control layer. The pitch is defined as the vertical distance a roof rises in each horizontal foot.

Transfer this measurement to the piece of framing. In this video you will learn all about common rafters. Some architectural designs call for plumb or vertical cuts as opposed to square cut tails. Use a tape measure to measure the entire width of your building.

Mark the cut line on the side face of each rafter tail. Measure as precisely as possible down to the 1 4 inch 0 64 cm 1 8 inch 0 32 cm or 1 16 inch 0 16 cm. Work from the scaffold and measure the distance from the upper end of the cut rafter to the point where the fascia meets the roof sheathing. Then divide the span by two to get the rafter run the length each rafter must cover.

Choose or determine a pitch the angle at which the rafters rise. The metric method for slopes less than 45 degrees shows the first number as 1 all the time so a 1 3 slope would mean a rise of 1 cm. This was then foamed to complete the air seal. For a 24 foot wide building the run would be 12.

Aligning with the overhang chalk line use a hand square to mark the cut line for a square fascia application or use a level to mark the plumb cut for the rafter tails. Use two nails in the end of each rafter. The traditional method has been rise inches 12 run inches. If the slope rises 6 inches in each horizontal foot the pitch is referred to as 6 in 12 or a 6 12 pitch.

First determine the width of the building the rafter span and the length for the number of rafters that will be needed. Go back and check out photograph 10. Measure the edge of the roof. Cut pieces so that the end joints between pieces fall in the center of a rafter tail.

For every 3 cm of run. Plumb or vertical with the fascia installed vertically parallel with the exterior wall surface and square with the fascia installed perpendicular to the roof pitch. When framing a gable or hip roof the final step is cutting the rafter tails for fascia board. Step 2 place a 2 by 6 board on sawhorses to lay out the first full length or common rafter.

Before you start cutting you first need to determine how long your roof rafters need to be and the angles at which you ll cut the top and bottom of the rafter.