Metal Siding Calculator
Count steel or aluminum panels and squares for walls, gable ends and accents, with a cost range you can trust.
Walls (feet)
Gables / triangles optional
Windows & doors to subtract
Tip: measure each wall's width × height at its widest points. A per-wall audit table appears below so you can check every number.
Your siding squares, panels and cost appear here.
Estimated from wall count and perimeter — confirm against your actual corners and openings.
Cost per sq ft: – · per square: –
| Surface | Area (sq ft) |
|---|
Panels, coverage width and squares
Metal siding is bought by the panel, and the number that drives your count is the panel's coverage width and length. Wider coverage means fewer panels for the same wall. Because metal is often run vertically on gable ends and outbuildings, capturing those triangular areas correctly matters as much as the main walls — this tool keeps them on separate lines.
Enter each wall and gable, remove your openings, and read panels and squares. Metal has slightly lower waste than lap siding on simple runs, but bump it up for lots of angled cuts.
How to fill it in (and what each field does)
Every field maps to a real measurement, so if you can read a tape you can use this. Walk through it top to bottom:
- Units + material: feet or meters, then the product you're installing — this sets coverage and a starting price.
- Walls: add a row per wall face with its width, height and count.
- Gables: base and rise for each triangle under the roof.
- Windows & doors: size and count for each, so their area is removed.
- Waste & cost: a percentage cushion plus optional labor and removal rates.
Hit calculate and the full breakdown appears below the form.
Gable-end metal
A gable end 30 ft at the base and 10 ft to the peak is ½ × 30 × 10 = 150 sq ft — 1.5 squares. Metal's long vertical panels cover it with minimal seams; add ~8% waste for the angled top cuts.
Where these numbers come from
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.
Metal siding details people ask about next
Panels and squares get you started, but metal has its own set of second questions, especially on outbuildings and modern homes.
- Panel profile: board-and-batten, corrugated and standing-seam-look panels cover different widths. Match the coverage to your exact profile.
- Gauge and finish: heavier gauge resists dents; a good paint finish (like a Kynar coating) holds color for decades. Both affect price more than quantity.
- Trim and closures: metal needs matching trim, closures and fasteners with washers. Budget these alongside the panels.
- Condensation control: on unheated buildings, plan a vapor control layer to avoid sweating behind the metal.
Enter your exact panel coverage above and the square count converts straight into a panel order for walls, gables and outbuildings alike.
Frequently asked questions
How do I calculate metal siding?
Is metal siding measured in squares?
How much waste for metal panels?
Can I use this for a metal building or barn?
Does it cover steel and aluminum?
From people who've used it
"Sided a pole barn from the panel count. Ordered once, no leftovers to speak of."