Siding Calculator
Squares and boxes of siding from wall area minus openings.
Enter your values
ⓘ Live results
Results
- Siding squares
- 14.19
- Net wall area
- 1,290 sq ft
- Boxes (2 squares each)
- 8
- Starter strip
- 150 ft
- J-channel
- 322 ft (estimate)
- Material cost
- $3,263.70
Working
- 1150 x 9 + 120 - 180 = 1,290 ft2 -> 14.19 squares
Quick answer
Siding area = wall area minus openings, plus waste. One square covers 100 sq ft; vinyl usually ships two squares per box.
squares = (wall area - openings) x (1 + waste) / 100
How to use the Siding Calculator
- 1Walk the perimeter and measure the wall height to the soffit.
- 2Add gable triangles (base x height / 2 each) and subtract windows and doors.
- 3Add 10% waste, more if the house has many corners and dormers.
Worked example
Using the values the calculator loads with:
Inputs
- Perimeter of house150 ft
- Wall height9 ft
- Gable area120 sq ft
- Window and door area180 sq ft
- Waste10 %
- Cost per square230 $
Results
- Siding squares14.19
- Net wall area1,290 sq ft
- Boxes (2 squares each)8
- Starter strip150 ft
- J-channel322 ft (estimate)
- Material cost$3,263.70
- 150 x 9 + 120 - 180 = 1,290 ft2 -> 14.19 squares
Frequently asked questions
Should I subtract every window?
Subtract anything larger than about 10 sq ft. Leaving small openings in the total covers the offcuts you will lose around them anyway.
How much extra should I order?
10% on a simple box-shaped house, up to 15 to 20% on a complex facade with dormers, bays and steep gables.
About this calculator
- Built and reviewed by James Whitfield · How we build and test calculators
- Report an error
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.