Roofing answer guide

What is a roofing square?

Understand roofing squares, square feet, shingle bundles, waste, measured roof area, and how roofers use squares to price and order asphalt shingles.

Reviewed - May 21, 2026

Short answer

A roofing square is 100 sq ft of roof surface area. Roofers use squares because shingle material, underlayment, tear-off, and labor are commonly planned or priced per square.

For a 1,200 sq ft measured roof with 10% waste, the roofing calculator estimates 13.2 roofing squares and 40 shingle bundles using the current 3-bundles-per-square planning default.

Keep measured squares and order squares separate: a 2,400 sq ft measured roof is 24.0 squares before waste, or 26.9 order squares and 81 shingle bundles with 12% waste.

Convert roof area to roofing squares

Roofing square conversion method

Measure roof surface area in square feet, not just the flat house footprint.
Add waste for valleys, hips, starter courses, ridge cap cuts, damaged pieces, and layout loss.
Divide the waste-adjusted order area by 100 sq ft to convert square feet into roofing squares.
Track measured squares before waste separately from order squares after waste so quotes and material takeoffs are compared on the same basis.
Multiply roofing squares by the shingle product's bundles per square to plan field-shingle bundles.
Confirm the exact product coverage before ordering because specialty shingles, starter, and ridge cap products can use different coverage.

Quick examples

1,000 sq ft roof

11.0 squares

Known roof area, 10% waste

1,200 sq ft roof

13.2 squares

Known roof area, 10% waste

2,400 sq ft roof

26.9 squares

Known roof area, 12% waste

Measured sections

16.9 squares

Four planes totaling 1,536 sq ft, 10% waste

6/12 pitch footprint

14.9 squares

40 ft by 28 ft, moderate roof, 10% waste

These generated examples use the current U.S. default roofing assumptions: 100 sq ft per roofing square, 3 bundles per square, known roof area as measured surface area before waste, and the entered waste buffer.

Worked example

1,200 sq ft known roof area, 10% waste.

Roofing squares

13.2 squares

1,320 sq ft order area including 10% waste

Shingle bundles

40 bundles

3 bundles per square planning default

Measured roof area

1,200 sq ft

Known roof area entered directly

DIY material total

$2,310–$5,742

Shingles, underlayment, flashing, and starter allowance

Contractor total

$6,006–$14,652

Materials plus tear-off and labor

Starter shopping list

architectural asphalt shingles 40 bundles
Underlayment, drip edge, flashing, starter, ridge cap 13.2 squares
Roofing nails and sealant As needed

This example is generated from the same calculator logic used on the Roofing calculator page.

Square feet vs roofing squares

One roofing square equals 100 sq ft of roof surface area, so 12 squares means about 1,200 sq ft before any waste allowance.
Roof surface area is not always the same as building footprint because pitch, overhangs, dormers, porches, and additions change the measured roof area.

Measured squares vs order squares

Measured squares describe the roof surface area before waste; order squares include the extra material allowance for cuts and layout loss.
Ask whether a quote's square count is measured area, waste-adjusted order area, or a rounded billing quantity before comparing bids.

Waste and ordering

Waste is added before converting to final order squares so cuts, hips, valleys, ridge work, and layout loss are included.
A simple roof may use a smaller waste buffer than a steep or cut-up roof, but most asphalt shingle plans still need some ordering margin.

Pricing and quotes

Contractor quotes often use squares for shingles, underlayment, tear-off, disposal, labor, and accessory allowances.
Compare quotes by measured squares, shingle line, waste, tear-off layers, decking repair, flashing, ventilation, cleanup, and warranty scope.

Common mistakes

Treating a roofing square as a 10 ft by 10 ft flat footprint instead of 100 sq ft of roof surface.
Skipping pitch, overhangs, dormers, valleys, hips, porches, or additions when estimating roof area.
Dividing measured area by 100 before adding waste, then forgetting to increase the order quantity.
Assuming field shingles, starter shingles, and ridge cap shingles all use the same bundle coverage.
Comparing quotes by bundle count alone without checking measured squares, waste, and product coverage.
Reading a quote's square count without checking whether tear-off, underlayment, flashing, disposal, and decking repair are included.

FAQ

How many square feet are in a roofing square?

One roofing square is 100 sq ft of roof surface area. A 1,200 sq ft measured roof is 12 squares before waste and 13.2 order squares with a 10% waste buffer.

How many roofing squares is a 2,400 sq ft roof?

A 2,400 sq ft measured roof is 24.0 squares before waste. With a 12% waste buffer, the generated example estimates 26.9 order squares and 81 field-shingle bundles.

Why do roofers use squares?

Squares make roof estimating easier because shingles, underlayment, tear-off, disposal, and labor are often priced or planned per 100 sq ft of roof area.

Is a roofing square the same as a bundle?

No. A square is an area measurement. A bundle is a package of shingles, and the calculator uses 3 bundles per square as a planning default for asphalt shingles.

Do I add waste before or after converting to squares?

Add waste to the measured roof area first, then divide by 100. This keeps cuts, valleys, hips, starter courses, ridge cap, and damaged pieces in the order quantity.

Can I use my house footprint to calculate roofing squares?

Footprint mode can help early planning, but ordering should use measured roof surface area when possible because pitch, overhangs, dormers, and additions change the area.