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Calculation Machine

Roof Shingle Calculator

Squares, bundles, nails and underlayment for a shingle roof.

Reviewed by the Calculation Machine team · How we check our maths

Your values

ⓘ Live results

Results
Squares needed
19.68 squares
Bundles (3 per square)
60
Actual roof area
1,789 sq ft
Underlayment rolls (400 sq ft)
5
Roofing nails
6,297 (about 2.6 boxes)
Material cost
$2,361.22

Working

  1. 11,600 ft2 x 1.118 = 1,789 ft2 -> 19.68 squares with waste

Quick answer

Roof area = footprint x pitch multiplier. One square is 100 sq ft and takes three bundles of standard architectural shingles.

The formula

squares = footprint x pitch factor / 100

Worked example

Worked example

Using the values the calculator loads with.

Inputs

  • Roof footprint1600 sq ft
  • Roof pitch6/12
  • Waste10 %
  • Cost per square120 $

Result

  • Squares needed19.68 squares
  • Bundles (3 per square)60
  • Actual roof area1,789 sq ft
  • Underlayment rolls (400 sq ft)5
  • Roofing nails6,297 (about 2.6 boxes)
  • Material cost$2,361.22

How to use the Roof Shingle Calculator

  1. 1Measure the building footprint under the roof, including overhangs.
  2. 2Choose the pitch - it converts the flat footprint into true sloped area.
  3. 3Add 10% waste, or 15% on roofs with lots of hips and valleys.

Frequently asked questions

How many bundles are in a square?

Three for standard three-tab and most architectural shingles. Heavier designer shingles can need four or five, so check the wrapper.

Do I include the overhang?

Yes. Shingles cover the eaves and rakes, so measure to the drip edge rather than the wall line.

About this calculator