Building How To: Help

Handy Calculators to Make Your Job Easier!

Roof Shingle Estimator

To calculate shingling requirements, you must know the actual roof area to be covered.

Find the total flat area of a roof by multiplying the width of the structure by the length of the structure.

If you do not know the pitch of the structure's roof, use this printable Roof Pitch Estimator to determine the figure.

Download Adobe Acrobat here if you cannot read the Roof Pitch Estimator PDF document. PDF document.

Once you know the pitch and total flat area, use the chart below to determine the actual surface area.

Each bundle of shingle covers an average area of 32 sq. feet.

PITCH	MULTIPLY FLAT AREA BY:
2/12	1.0138
3/12	1.0308
4/12	1.0541
5/12	1.0833
6/12	1.1180
7/12	1.1577
8/12	1.2019
9/12	1.2500
10/12	1.3017
11/12	1.3566
12/12	1.4142
13/12	1.4743
14/12	1.5366
15/12	1.6008
16/12	1.6667