HomeExpertly
www.homeexpertly.comSiding Material Calculator
Estimate how much siding you need for a house or project. Enter the wall perimeter and height, subtract the doors and windows you won't side over, and add any gable or bump-out area — then set a waste allowance and the coverage and price per box. You'll get the net wall area, how many squares (100 sq ft each) and whole boxes to buy, and the material cost, with a step-by-step wall-area breakdown, a by-waste comparison, a chart, and a downloadable PDF report.
US feet and inches. Net area = perimeter × height − openings + gables; boxes = net area × (1 + waste) ÷ coverage per box, rounded up. 1 square = 100 sq ft. Coverage, exposure and lap vary by product, and trim, corner posts, starter strip, J-channel and fasteners are ordered separately. Measure each wall, check the manufacturer's coverage, and confirm quantities with your supplier before buying. An estimate, not professional advice.
1
Wall size
ft
ft
2
Openings & gables
sq ft
sq ft
3
Siding & cost
8%
10%
15%
%
sq ft
$
Siding boxes needed
— boxes
Enter the walls, then click Calculate
Net wall area
—
to cover
Squares (with waste)
—
1 sq = 100 sq ft
Material cost
—
estimated
Siding summary
Enter the walls
We work out the net wall area (walls minus openings plus gables), add a waste allowance, and convert it to squares and whole boxes.
Siding breakdown
Wall perimeter—
Wall height—
Gross wall area—
Openings subtracted—
Gable / extra added—
Net wall area—
Waste allowance—
Area with waste—
Squares (100 sq ft)—
Coverage per box—
Boxes needed—
Total material cost—
Result summary
Boxes needed
—
Squares
—
Material cost
—
Net area
—
Gross area
—
Cost / sq ft
—
Wall area breakdown
| Item | Area | Running total |
|---|---|---|
| Enter the walls to see the breakdown | ||
By waste allowance
| Waste | Area + waste | Boxes | Cost |
|---|---|---|---|
| Enter the walls to compare | |||
Visualizations
Boxes needed by waste allowance (highlighted = your %)