Free Siding Calculator
Calculate how much siding you need for a house. Deducts for windows and doors, and accounts for waste.
feet
feet
%
Siding Needed (with waste)
1,317 sq ft
Gross Wall Area1,440 sq ft
Opening Deductions243 sq ft
Net Siding Area1,197 sq ft
Siding Squares13.2
Siding Needed (with waste) vs Total Wall Perimeter
How to Calculate Siding
Formula
Net Area = (Perimeter × Height) - (Doors × 21 sq ft) - (Windows × 15 sq ft)
Siding Needed = Net Area × (1 + Waste %)
Siding is often sold in "squares" (100 sq ft). Vinyl siding panels typically cover about 2 squares (200 sq ft) per box. Lap siding exposure varies by product.
Example Calculation
A house with 160 ft perimeter, 9 ft walls, 3 doors, 12 windows, 10% waste.
- 01Gross area = 160 × 9 = 1,440 sq ft
- 02Openings = 3 × 21 + 12 × 15 = 63 + 180 = 243 sq ft
- 03Net area = 1,440 - 243 = 1,197 sq ft
- 04With 10% waste = 1,197 × 1.10 = 1,317 sq ft
- 05Siding squares = 1,317 / 100 = 13.2 squares
Frequently Asked Questions
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