How To Layout A Roof Rafter

Facing the long side of your material measure down from the top edge 8.

How to layout a roof rafter.

On a shed roof rafter run is the distance from a ledger on the main building to the outside of an addition wall or porch carrying beam. In the gable roof example shown here a rafter with 6 in 12 pitch rises 6 in. Floor beam span tables of residential structural design we will now look at roof rafter and beam design. Rafter layout and cutting sequence.

Use a circular saw or jigsaw to make the cut. Position the square with both the 8 inch on the outside edge of the tongue and the 12 inch on the blade on the upper edge of the board. Then draw a line across the width of the plywood from that mark. Just share the link.

For every foot of run. Place the square as before aligning the 6 mark of the tongue and 12 mark of the body with the top edge of the rafter material. Continuing on from part 3. 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.

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. Let s consider a basic gable wood roof framing design. To lay out a common rafter you need the pitch of the roof expressed in units of rise per foot of run. Draw a line down the edge of the tongue as shown in illustration b of the roof layout.

The easy way to lay out and build your rafters. We need to adjust the total run 73 inches in our example by subtracting 1 1 2 inches the full thickness of the ledger adjusted run 71 1 2 inches. Marking the birdsmouth and the ridge board setback. Rafter layout with a framing square this example is for a roof with an 8 12 pitch position the square at the end of the rafter board with the tongue on your left and facing away from you.

Do not download and re upload this video. Align the back edge of the tongue with the 187 7 8 mark. Use a tape measure to measure the entire width of your building. Layout your sheet of plywood on sawhorses.