Worked examples

Shingle Estimate for a 1,800 Sq Ft Roof

Worked shingle estimate for 1,800 square feet of roof area with waste, squares, and bundle count.

Planning result

For 1,800 sq ft of measured roof area with 15% waste, plan 2,070 sq ft, or 20.7 roofing squares. At 3 bundles per square, this rounds to 63 field-shingle bundles.

Assumptions

Measured roof area 1,800 sq ft after pitch and roof planes are included.
Waste 15% for a more cut-up roof.
Bundle rate 3 bundles per roofing square.
Accessories Accessory materials are not included in field-shingle bundles.

Calculation

Step Result Formula
Measured roof area 1,800 sq ft Given roof surface area
Waste-adjusted area 2,070 sq ft 1,800 x 1.15
Roofing squares 20.7 squares 2,070 / 100
Bundles 62.1 bundles 20.7 x 3
Practical buy 63 bundles Round up to full bundles

Why waste is higher here

Hips, valleys, dormers, skylights, and short roof planes can increase cut waste. The percentage should reflect roof complexity.

Confirm product packaging

Some shingles do not use exactly 3 bundles per square. Always check the selected product before ordering.

Next step

Use the linked calculator or planning hub to adjust dimensions, waste, coverage, depth, spacing, or product packaging for the real project.

FAQ

How many bundles for 1,800 sq ft of roof?

With 15% waste and 3 bundles per square, plan about 63 field-shingle bundles.

Why use 15% waste?

More complex roofs often create more cut waste than simple gable roofs.

Does this include underlayment?

No. Underlayment is estimated by roll coverage separately.