How To Figure Out Roof Pitch With Speed Square

A roof s pitch is determined by how much it rises vertically for every foot it runs horizontally.

How to figure out roof pitch with speed square.

Place the pivot point on the square against the bottom of the rafter and align the 90 degree angle side of the square with the pencil mark. Measure the vertical distance from roof to level. Let s say it is equal to 1 5 m. Use a level and a pencil to make a plumb vertical line on one face of an existing rafter.

A speed square and level can be used to easily find the pitch of a roof. The pitch of the roof is the rise over a 12 inch run. How roof pitch is calculated to accurately calculate the area of your roof you must first determine its slope or pitch. Set the level on the edge of the speed square as shown below then place the heel of the speed square on a rafter or gable edge of the roof.

Move the tape measure along the the roof until it hits the level at exactly the 12 inch mark. Thus a moderate 6 in 12 roof pitch means that the roof rises 6 inches vertically for every 12 horizontal inches it runs. Rafter rise run 1 5 6 2 25 36 38 25rafter 38 25 6 18 m. For example a 4 12 pitch roof that is 100 square feet.

Next multiply the footprint of the roof by the multiplier below for your roof pitch to find the overall roof area. Place the level horizontally along the rafter until it contacts the roof sheathing avoiding any protruding roof nails. Read the pitch on the side of the rafter square. 100 1 054 105 4ft 2.

With a torpedo level and a speed square you can pretty accurately gauge the pitch of any roof with a gable end photo 1. Working from the interior side of the roof you ll need access to a roof rafter to measure the pitch. Extend it upward so it is perpendicular to the level. Calculate the rafter length substituting these values into the following formula.

Then place a torpedo level on the fat base of the rafter square and adjust the square until the level is level. Pitch rise run 1 5 6 25. If you need to find the pitch of an existing roof all you need is a level and a tape measure. How to measure roof pitch with a speed square.

Use our roof pitch calculator to find the pitch of your roof. Measure the rise of your roof. Roof pitch area multipliers.