Roof panel material estimator

Metal Roofing Calculator

Estimate metal roof panels from eave length, rafter length or slope length, panel coverage width, end laps, waste allowance, and price per panel. Use it for quick standing-seam or corrugated panel ordering checks.

Units

Roof eave length (ft) Slope / rafter length (ft) Panel coverage width (in) Stock panel length (ft) Waste / cut allowance (%) Price per panel ($)

Panels to buy

—

Panel rows

—

Slope roof area

—

Estimated panel cost

—

Metal roofing count is a material estimate

Confirm manufacturer side-lap rules, trim, ridge cap, closures, fasteners, underlayment, snow guards, hips, valleys, roof penetrations, and local wind requirements before ordering.

Android App

Need metal roofing calculator estimates hands-free?

The Android app adds the jobsite workflow: voice input, offline use, material lists, PDF export. Free, no ads, no accounts.

Get the Free App Free. Built for Android phones. Donations welcome.

Saved you a mistake? Support VibeCalc

Roof Pitch Calculator

Convert rise and run before deciding roof slope and panel length.

Rafter Length Calculator

Calculate slope length from run and pitch when the rafter length is unknown.

Roof Shingle Calculator

Compare asphalt-shingle squares and bundles for the same roof footprint.

View all

Metal Roofing Calculator formula

Panel rows = ceil(eave length ft ÷ (panel coverage in ÷ 12))Panel rows = ceil(eave length m ÷ (panel coverage mm ÷ 1000))

Panels per row = ceil(slope length ft ÷ stock panel length ft)

Base panels = panel rows × panels per row

Panels to buy = ceil(base panels × (1 + waste %))

Slope roof area = eave length × slope length

Example

A 40 ft eave with 16 ft slope length and 36 in panel coverage needs 14 panel rows. If panels are 16 ft long, that is 14 base panels. With 10% allowance, buy 16 panels.

Metal Roofing Calculator FAQ

How do you calculate metal roof panels?+

Divide eave length by the panel coverage width to get rows, divide slope length by stock panel length to get panels per row, multiply, then add waste and round up.

Is panel coverage width the same as actual width?+

No. Use exposed coverage after side laps, not the raw sheet width. The manufacturer or supplier should list the coverage width.

Does this include trim and screws?+

No. This estimates roof panels only. Ridge cap, eave trim, rake trim, closures, screws, underlayment, and flashing are separate materials.

Can I use rafter length as slope length?+

Yes for a simple roof plane. Use the roof slope length from eave to ridge, including overhang if panels run to the eave edge.