Aluminum Siding Calculator

Aluminum siding is lightweight, dent-prone and very common on mid-century homes, which means a lot of aluminum questions are really about repainting rather than replacing. Either way the starting point is the same: your wall area in squares. Once you know that, you can price panels for a replacement or paint and primer for a refresh.

This calculator returns panels and squares from your measurements and gives you the area figure you need for a paint takeoff. For replacement, set the material price; for painting, use the square footage against your paint's coverage.

For a repaint, ignore panels and use net area: a gallon of exterior paint covers roughly 350 sq ft per coat. A 1,600 sq ft wall area needs about 5 gallons per coat, so 9–10 gallons for two coats plus primer.

The measuring method follows standard exterior-takeoff practice: gross wall area minus openings, converted to squares at 100 sq ft each, with a waste factor for offcuts. Coverage and waste ranges reflect published manufacturer installation guidance from makers such as James Hardie and vinyl producers, and cost ranges reflect commonly reported US installed prices. Local prices, product lines and codes vary, so treat the output as a well-grounded planning estimate — a field measure and your contractor's quote govern the final order.

One figure rarely tells the whole story. Confirm these points and your aluminum siding estimate becomes an order you can actually place with confidence.

• Confirm coverage: the default coverage is a planning figure. Check the exact coverage printed on your product's box or spec sheet and adjust it if it differs, since even a small change moves the piece count on a big wall.
• Match the waste to your walls: keep 10% for a simple rectangular house, and raise it toward 15% for gables, dormers, bay windows and lots of angled cuts, because those details generate short offcuts you can't reuse.
• Account for accessories: starter strip, trim, inside and outside corners, flashing and fasteners are all part of a complete order, not an afterthought — the takeoff above estimates each so your material list is whole.
• Keep a spare: hold back a piece or a full box for future repairs, since profiles and colors get discontinued over time and an exact match years later is hard to find.
• Time your order: have material delivered close to the start date, stored flat and dry, so it isn't sitting exposed or getting damaged before the crew arrives.

Re-run the numbers above after any change and lean on the per-wall audit to verify each surface one at a time, so what you order matches what the wall actually needs rather than a rough guess. That small habit is the difference between one clean delivery and a mid-project trip back to the supplier.