How to use this calculator
- Enter Roof area in sq ft.
- Enter Panel coverage in in.
- Enter Panel length in ft.
- Press Calculate. The highlighted row is your order quantity; the note beneath it translates the number into real-world terms.
Formula & constants
Panels are sold by coverage width (36 in corrugated, 12–16 in standing seam). Panels per side = roof width ÷ coverage width; length = eave-to-ridge slope length. Order 5% extra for laps and cuts. Every default in the fields above is editable — when your supplier’s spec sheet lists a different density, coverage rate or price, enter that number instead. The waste and compaction allowances follow common trade practice; see our methodology page for the derivation of each formula and the standards it references.
Where this fits in the project
Roof takeoffs start from the footprint corrected by pitch: get true area from the roof square footage calculator, convert to squares, then to shingle bundles or metal panels. Size gutters from the same perimeter measurement.
How this connects to your project
No quantity stands alone — each material in the chain depends on the ones around it. These are the planning steps that pair with the metal roofing calculator:
- Roofing Calculator — Metal is a roofing material option.
- Shingle Calculator — Metal roofing vs asphalt shingles comparison.
- Roof Pitch Calculator — Metal panels have minimum pitch requirements.
- Roof Square Footage Calculator — Metal panel quantity comes from roof area.
- Roofing Cost Calculator — Metal roofing has different cost structure than shingles.
- Gutter Calculator — Gutters work with all roofing types including metal.
Frequently asked questions
Exposed fastener or standing seam?
Exposed-fastener costs half but screws need re-tightening every 10–15 years; standing seam hides clips and lasts longer.
Can metal go over old shingles?
Often yes, over one flat layer with furring or synthetic underlayment — verify local code and manufacturer approval.
Last verified: — prices reflect current national averages. See our methodology.
Estimates are for planning. Material densities, coverage rates and prices vary by region and supplier — confirm final quantities before ordering, and check local code where structural or electrical work is involved.