Siding Calculator
Estimate exterior siding area, squares, cartons, starter trim, corner trim and material cost after opening deductions.
Default project preview
13.42 squares
Net wall area
1,220 ft²
Cartons
7
Starter strip
140 ft
Corner trim
36 ft
Calculator
Build the material order
Your order will appear here
Enter the project details and calculate a rounded material estimate.
Methodology
Transparent calculation
BuildMeter converts every input to a consistent internal unit, applies the selected allowance, and rounds products up to whole purchasable units.
Net wall area = perimeter × wall height + gables − openings. Order area = net area × waste factor. Cartons = round up (order area ÷ carton coverage).
FAQ
Siding Calculator questions
What is one siding square?+
In imperial measurements, one siding square covers 100 square feet.
Should gables be measured separately?+
Yes. Add the combined triangular or irregular gable area to the rectangular wall area.
Does this include all trim accessories?+
No. It estimates starter and outside corners only; product-specific channels and flashing require a detailed takeoff.