What is a roofing square?

One roofing square equals 100 square feet of roof area. Most roofing materials are sold by the square, with 3 bundles of shingles typically covering one square.

How do I measure roof pitch?

Roof pitch is measured as the vertical rise over a 12-inch horizontal run. For example, a 6/12 pitch rises 6 inches for every 12 inches horizontally. Use a level and tape measure, or a pitch finder app.

How much waste factor should I add?

Add 10-15% waste factor for simple roofs, 15-20% for complex roofs with valleys, hips, or multiple angles. This accounts for cutting, starter strips, and ridge caps.

Pro Roofing Calculator

Calculate total roof area, squares, shingle bundles, and estimated materials cost.

Roof Dimensions

Base Length Feet

Base Width Feet

Roof Pitch Rise over 12"

Waste Factor % (10-15% rec.)

Shingle Price Per Square (100 sq ft)

Estimate

Roof Area

0 sq ft

Squares

Shingle Bundles

0 Bundles

Assuming 3 bundles per square.

Material Cost

Underlayment

0 Rolls

* Estimates include waste factor. Rolled roofing/felt based on 4 squares per roll.