Metal Roofing Calculator

Calculate metal roofing panels, screws, ridge caps, trim, and accessories. Includes standing seam, corrugated, and R-panel options.

How to Use This Calculator

Metal roofing calculation requires understanding panel widths, overlaps, and accessories. This calculator helps you estimate panels, screws, trim, and all the components needed for a complete metal roof installation.

  1. Enter roof dimensions or total squares (1 square = 100 sq ft).
  2. Select your roof pitch - this affects the actual surface area to cover.
  3. Choose your panel type - standing seam, corrugated, R-panel, etc.
  4. Enter the number of hips and valleys for trim calculations.
  5. Specify ridge length if different from roof length.

Why This Matters

Metal roofing is a significant investment that pays off with longevity, energy efficiency, and low maintenance. Accurate material estimation prevents costly mid-project orders and ensures you have matching panels from the same production run. Unlike shingles, metal panels come in various widths and profiles that significantly affect coverage calculations.

  • Calculate panels based on coverage width, not nominal width
  • Account for roof pitch in area calculations
  • Include all trim and accessories
  • Estimate screws and closure strips
  • Budget for complete installation costs

Worked Examples

Simple Gable Roof

A 30' x 40' roof area with 4/12 pitch using standing seam panels.

Calculation: 1,200 sq ft x 1.05 (pitch) = 1,260 sq ft actual area
Result: 80 panels (16" coverage), 1,000 screws, 30 ft ridge cap.

Hip Roof with Valleys

A 2,500 sq ft home footprint, 6/12 pitch, 4 hips, 2 valleys.

Calculation: 2,500 x 1.12 (pitch) = 2,800 sq ft + hip/valley trim
Result: 175 panels, 2,200 screws, extensive hip and valley flashing.

Corrugated Metal Barn

A 40' x 60' barn with low slope (3/12) using corrugated panels.

Calculation: 2,400 sq ft x 1.03 = 2,472 sq ft with 24" coverage panels
Result: 104 panels, 2,000 screws, minimal trim requirements.

Common Mistakes to Avoid

  • Using nominal panel width instead of coverage width - overlap reduces coverage.
  • Forgetting pitch multiplier - steeper roofs have significantly more surface area.
  • Underestimating trim and accessories - these add significant cost.
  • Not ordering from same lot - color can vary between production runs.
  • Skipping underlayment - moisture barriers are essential under metal.

Frequently Asked Questions