Measuring Roof Rafters

Calculate the span of.

Measuring roof rafters.

Subtract the width of your ridge beam. Here the number is 1166 66 inches. If your project had a rafter length of 8 or less a safe and strong method is to use 2x8 framed 16 on center. Decide how steep a slope you want your roof to have.

Here the number is 941 86 inches. On construction calculators slope is often called pitch. Measure the length and width of the building. Marking out the roof rafter lengths onto the timber before cutting step 1.

The slope you choose will mostly be a matter of preference. With the tape measure hooked onto the top end transfer your two rafter lengths onto. From here mark a line every 16 across the front lentil. On a full gable roof this is equal to half the building width minus half the ridge thickness.

Measure the width of your building. Planning the dimensions of a new roof 1. Divide the adjusted width. The results are automatically fired.

Before you can mark the rafter lengths and layout check the. Print full scale rafter cut templates and birdsmouth templates fold template over rafter to mark or cut through. In our example we have a 7 12 roof 7 inches of rise for every foot of run. Calculate the length of common rafters with this free and easy online tool by entering a dimension for the roof width selecting a pitch for the roof and the thickness of the ridge.

The ridge beam is the vertical piece of plywood which will form the peak of. Mark the plumb cuts. Roof rise this should be calculated from the base of the roof to the highest point of the roof gable the peak. As a general rule roofs that have a high human occupancy rate should be framed with rafters every 16 structures such as sheds or barns can be frames with rafters every 24 again make sure to consult local codes.

See rafter run to outer wall calculator below. Rafter run is the horizontal distance the rafter travels. Half building width minus 1 2 ridge thickness. Determine the camber along the timbers length.

Use a tape measure or laser measuring tool to find the dimensions of. Determine the pitch of the roof which is the angle that rafters rise from the outside walls to the ridge. Rafter run outer wall this should be measured starting from the center of the roof span and then extending to the very edge of the exterior wall. Calculating rafter length 1.

Allow for ridge thickness when determining rafter run to outer wall. The second number is the benchmark for typical pitched roof calculations. Before you start cutting you first need to determine how long your roof rafters. Measure the rafters begin by measuring across the front lentil and finding the center.