metal roof calculator

Metal Roof Calculator

Metal roof panel count starts with pitch-adjusted roof area, then divides by the coverage area of each panel.

Inputs

Results

Immediate estimate

Metal roof panels39 panels1,377.42 sq ft adjusted roof area

Base roof area1,252.2 sq ft

Pitch factor1.118

Panel coverage36 sq ft

Roofing squares13.77

Shopping list

39 panels Metal roof panels — Add trim, ridge, fasteners, closures, and underlayment separately.

Diagram

Metal roof panels

Pitch-adjusted roof area is divided by panel coverage area.

Roof plane
Panel width
Panel length

How this calculator works

Estimate metal roof panel count from building footprint, pitch, panel coverage width, panel length, and waste.

Area model

The calculator multiplies building footprint by a pitch factor to estimate roof surface area.

Panel model

Panel count uses coverage width, panel length, and waste. It does not replace a roof-plane takeoff.

Ordering gap

Trim, ridge cap, rake, eave, valley, closures, fasteners, underlayment, and snow guards are separate material lines.

Roof areafootprint x pitch factor

Adjusted arearoof area + waste

Panelsadjusted area / panel coverage, rounded up

Assumptions

Roof shape: Simple footprint-based roof estimate; measure each roof plane for ordering.
Panels: Panel count uses coverage width, not raw panel width.

Worked examples

Simple 6:12 metal roof

Simple early panel count.

39 panelsMetal roof panels

Steep roof

Shows steep-roof caution.

29 panelsMetal roof panels

FAQ

Is panel width the same as coverage width?

Not always. Use coverage width after laps or seams, not the raw panel width.

Does this work for complex roofs?

Use it only for early estimates. Complex roofs should be measured by each roof plane.

Does it include trim and fasteners?

No. The shopping list only estimates field panels.

Sources and review

Roof measurement and shingle planning, GAF. Accessed 2026-07-16.
Roof Replacement Costs, GAF. Accessed 2026-07-16.

Reviewed 2026-07-16. Planning estimates only; confirm project-specific requirements.