Roof Estimating Formulas

Ranch house using asphalt roof shingles.

Roof estimating formulas.

To get the slope of your roof based on degrees roof rise or x inches per 12 run use our roof pitch calculator. Medium low slope roof pitch of 3 or 4. Rafter rise run this formula is from the pythagorean theorem. The average roof replacement cost is 4 200 6 600 on a 1 600 sq ft.

Medium slope roof pitch of 6. Roof pitch roof pitch is the measurement of a roof s vertical rise divided by its horizontal run. Otherwise use the table or diagram below. Thus a moderate 6 in 12 roof pitch means that the roof rises 6 inches vertically for every 12 horizontal inches it runs.

Use the following formula which also describes a right triangle. Roofing cost can vary widely depending on the size and complexity of your roof type of materials you use as well as your location. L 30 feet h 12 feet 30 12 2 180 square feet. Medium steep slope roof pitch of 9.

Here are the equations you may use to solve for the length of the slope and the rafter. Steep slope roof pitch of 12 or 45 degrees. The length l times the height h of a triangle is twice its area a2. You can also calculate roof pitch even without using a roof slope calculator.

To accurately calculate the area of your roof you must first determine its slope or pitch. 1 roof square 100 square feet. However if you use premium materials such as metal wood shingles clay tile etc the cost of your roof will be at least 9 500 16 000. A roof s pitch is determined by how much it rises vertically for every foot it runs horizontally.