Roofing material calculator
Estimate roofing squares, shingle bundles and material area for a roof project.
Roofing material calculator
Estimate roofing squares, shingle bundles and material area for a roof project.
Enter your roof dimensions to see the material estimate.
Roofing squares
Project summary
How it works
These are material estimates, not structural engineering specifications. Consult a qualified roofer for structural and code compliance.
Roofing material calculator
What a roofing square actually is
Roofing materials are sold by the square, and one square covers 100 square feet of roof surface. That is the unit every supplier and installer uses, and it is the number you need when pricing materials. This calculator converts your roof dimensions into squares and then into the number of shingle bundles you need to buy.
Pitch changes everything
A roof is not flat, which means the actual surface area is larger than the floor area underneath it. The steeper the pitch, the more surface area per square foot of floor. A 4/12 pitch adds about 6 percent to the surface area. A 12/12 pitch nearly doubles it. The calculator applies the correct multiplier for whatever pitch you enter.
Why hip roofs need more material
A gable roof has two sloping sides meeting at a ridge. A hip roof has four sloping sides, and the hip rafters add material at the transitions between slopes. The calculator accounts for this by adding approximately 5 percent to the surface area for hip roofs compared to the same dimensions on a gable.
Frequently asked questions
How many shingles do I need for a 2000 square foot roof?
A 2000 square foot plan area at a 4/12 pitch has an actual roof surface of about 2120 square feet, or roughly 21 squares. Standard three-tab shingles require 3 bundles per square, so you would need about 64 bundles. Add 10 percent for waste and you are ordering about 70 bundles. Enter your own dimensions above for the exact figure.
What is a roofing square?
One roofing square equals 100 square feet of roof surface area. It is the standard unit that roofing materials are sold and priced by. If your roof measures 2500 square feet of actual surface, that is 25 squares. The calculator converts your plan dimensions and pitch into the correct square count.
How many squares of shingles do I need for a 2000 square foot roof?
A 2000 square foot roof needs approximately 20 squares of shingles, since one square covers 100 square feet. Add 10 percent waste for cutting and you need about 22 squares. The calculator gives you the precise number based on your roof dimensions, pitch and waste factor.
How much does a new roof cost?
Asphalt shingle roofs typically cost between 3 and 7 dollars per square foot installed. A 2000 square foot roof might run 6000 to 14000 dollars. Metal, tile and slate cost significantly more. The calculator estimates material quantities, and you can multiply by your local price per square to get a budget figure.
How long does a roof last?
Asphalt shingles last 20 to 30 years depending on quality and climate. Architectural shingles last longer than three tab. Metal roofs last 40 to 70 years. Tile and slate can exceed 50 years. The calculator helps you estimate material costs for replacement so you can plan for the expected lifespan.
Do I need a permit to replace my roof?
Most jurisdictions require a roofing permit for a full replacement. Repairs and re-roofing over existing shingles may not require one depending on local code. Check with your building department. The calculator produces a material list that supports your permit application.
How many bundles of shingles are in a square?
Standard three tab shingles come three bundles per square. Architectural shingles may also be three bundles per square but cover more area per bundle. The calculator converts squares to bundles based on the shingle type you select.
What about the underlayment and ice shield?
Most roofs need felt paper or synthetic underlayment across the entire deck. Ice and water shield goes along eaves, valleys and around penetrations. The calculator includes underlayment in the material list based on your roof area. Your local code specifies the ice shield requirements for your climate zone.