Question 1

What is a roofing square?

Accepted Answer

A roofing square is a unit of measurement equal to 100 square feet (about 9.3 m²) of roof surface. Roofers and material suppliers price and sell by the square. Shingles typically come in bundles that cover 1/3 of a square, so 3 bundles = 1 square.

Question 2

How does roof pitch affect material needs?

Accepted Answer

Steeper roofs have more actual surface area than their footprint. The pitch multiplier (e.g., 1.12 for 6:12 pitch) is used to convert footprint area to roof area. A 6:12 pitch roof has 12% more area than its flat projection.

Question 3

How much waste should I add for roofing?

Accepted Answer

Add 10-15% for simple gable roofs, 15-20% for hip roofs with many valleys, and 20% or more for complex cut-up roofs. Starter strip and ridge cap shingles add to material needs. Always round up to the nearest bundle.

Question 4

What is a bundle of shingles?

Accepted Answer

A bundle of architectural or 3-tab shingles covers about 33.3 square feet (1/3 of a square). Most shingle bundles contain 21-29 shingles depending on type. Three bundles typically cover one roofing square, but high-definition or luxury shingles may have different coverage rates.

Roof Area

Building Footprint

Pricing & Waste