Siding Calculator
Panels and packs using effective exposed dimensions.
How it works
Subtract openings, add the allowance, divide by one unit's effective area, then round up to whole units and packs. This estimates quantities by area; it does not optimize the cutting layout.
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How the Siding Calculator works
This siding calculator estimates panels and full packs from net wall area. Use exposed coverage dimensions, including the effect of overlaps, instead of measuring the entire panel including its lock.
Panels from net wall area
For 1,000 ft² of wall with 100 ft² of deductible openings, the net area is 900 ft². A 12 ft panel exposing 8 in covers 8 ft². With a 10% allowance, the requirement is 124 panels; at 10 per pack, purchase 13 packs containing 130 panels.
Square coverage and trim
One siding square represents 100 ft². A carton rating may already account for the product profile and overlap, so compare your calculated panel area with the manufacturer coverage.
An area estimate does not optimize individual wall courses. Gables, short wall sections and small windows can leave offcuts that are unusable elsewhere. Starter strips, corners, J-channel, flashing and fasteners are separate quantities. Estimate backing insulation separately.
FAQ
Can I use floor area? expand_more
No. Measure the exterior wall surfaces that will actually receive siding.
Should all window area be deducted? expand_more
Deduct it when the layout reduces the purchase; small openings often leave panel cutting losses.
Does the price include trim? expand_more
No. It multiplies full packs by the entered pack price and excludes accessories, delivery and labor.