Metal Roofing Calculator
Estimate metal roofing squares, weight, and coverage for standing seam, corrugated, and stone-coated panels.
Your Metal Roofing Estimate
- Enter roof footprint — measure from the ground. Pitch multiplier handles slope.
- Select pitch — standing seam works at 1/12+; exposed-fastener needs 3/12 minimum.
- Choose panel type — affects weight. Ordering is by the square.
- Set waste higher — metal waste runs 15–25% due to custom cuts. Higher for complex roofs.
- Order trim separately — ridge cap, drip edge, and flashing are not included.
Estimating Metal Roofing Materials
Metal roofing is ordered by the square (100 sq ft) like shingles, but panels are not sold in bundles. Your supplier cuts panels to your specified length and calculates panel count based on their coverage width — typically 12 to 36 inches depending on the profile.
Standing seam panels cost more upfront but last 40–70 years with virtually no maintenance. Corrugated panels cost less but need fastener re-sealing after 15–20 years. Both significantly outperform asphalt shingles in longevity, energy efficiency, and wind resistance.
Metal Roofing Cost by Panel Type
Higher upfront cost, but dramatically longer lifespan changes the total cost of ownership:
| Panel Type | Installed Cost/Square | Lifespan | Maintenance |
|---|---|---|---|
| Corrugated Steel | $350–$550 | 30–45 years | Re-seal fasteners every 10–15 yr |
| Standing Seam Steel | $700–$1,200 | 40–70 years | Virtually none |
| Stone-Coated Steel | $800–$1,400 | 40–50 years | Minimal |
| Aluminum Standing Seam | $900–$1,500 | 50+ years | None — no rust |
Architectural asphalt shingles cost $350–$600/square installed but last 25–30 years. Over 50 years, one standing seam roof costs less than two shingle roofs plus the labor for tear-off and reinstall.
How the Calculator Works
Standard area math with pitch adjustment:
Total area = Roof area × (1 + Waste %)
Squares = Total area ÷ 100
Weight = Squares × Weight per square
Your metal supplier converts squares into panel count based on their specific panel width and your custom cut lengths.
Related Calculators
Metal roofing panels require accurate area and pitch data. Browse the construction calculator collection.
Frequently Asked Questions
What is the minimum pitch for metal roofing?
Standing seam metal can go as low as 1/12 (nearly flat) with proper seam details. Exposed-fastener panels (corrugated, R-panel) need a minimum 3/12 pitch to prevent leaks at screw penetrations. Always check the manufacturer's specification for your panel.
Is a metal roof louder in rain?
With proper solid sheathing (plywood or OSB) and underlayment beneath the panels, a metal roof is no louder than shingles. The noise concern applies mainly to agricultural buildings where panels attach directly to purlins with no decking.
Can you install metal roofing over existing shingles?
Yes, in many cases. Metal panels can be installed over one layer of existing shingles with furring strips (battens) to create an air gap. This saves on tear-off labor and disposal costs. Check local codes — some jurisdictions require tear-off regardless.
How long does metal roofing last?
Standing seam metal roofing typically lasts 40–70 years. Exposed-fastener panels last 20–40 years depending on coating quality and climate. Steel roofing with Kynar 500 coating is the most durable finish. Aluminum and zinc roofs can last 50–100 years in coastal environments where steel would corrode.
How much does metal roofing cost per square?
Exposed-fastener steel panels cost $150–$350 per square installed. Standing seam systems run $400–$900 per square. Metal roofing costs more upfront than asphalt shingles but lasts 2–3 times longer, making lifetime cost often lower. Energy savings from cool-roof coatings also offset some of the premium.