Calculator · 2026
Metal roof calculator
How do I estimate a metal roof?
Panels per side = eave length ÷ panel coverage width, rounded up; panel length = the slope from eave to ridge. Installed cost is about $900 to $1,600 per square for standing seam and $500 to $1,300 for exposed-fastener panel.
How it is calculated
- Panel length = (half the span + overhang) x pitch factor.
- Eave length = house length + an overhang at each gable end.
- Panels per side = eave length ÷ panel coverage, rounded up; two sides on a gable.
- Squares = roof area x 1.10 (for 10% waste) ÷ 100; cost = squares x the installed range per square, plus tear-off.
Costs here use US-average labor. For your state or metro, with decking and extras, use the roof cost calculator set to metal. Background: metal roof cost, metal vs shingles, metal over shingles.
Trim (ridge cap, eave and rake trim, closures), underlayment and fasteners are ordered separately by the linear foot; your supplier will take them off the same measurements.
Sources for the figures on this page
Panel coverage widths
- McElroy Metal R-Panel, retrieved 2026-09-28:
With a 1¼" rib height and 36” wide coverage, R-Panel delivers outstanding spanning capability for both roof and wall applications
- McElroy Metal Maxima, retrieved 2026-09-28:
With leg heights from 1 ½” to 3” and pan widths from 12”-24”, our Maxima series is one of the most robust offerings in the industry.
- McElroy Metal Maxima (product schema), retrieved 2026-09-28:
"Panel widths","value":"1.5\"; 2\" & ADV: 12\", 16\", 18\"; 3\": 18\", 24\""
Installed cost per square
- HomeGuide (page dated 2026), retrieved 2026-09-25:
A standing seam metal roof costs $9 to $16 per square foot installed ... Table: Seamless metal roofing materials $4 – $8 [per sq ft]; Installation labor $5 – $8 [per sq ft] ... Installing a standing seam metal roof costs $5 to $8 per square foot for the labor alone.
- HomeGuide (page dated 2026), retrieved 2026-09-25:
Standing seam | $4 – $8 [material $/sq ft] | $9 – $16 [installed $/sq ft] | $900 – $1,600 [installed per square]
- Fixr (page dated January 23, 2026), retrieved 2026-09-25:
Standing seam: "$7 – $30" per sq ft ... The average labor cost to install a metal roof is between $3 and $12 per square foot
- HomeAdvisor (page dated June 19, 2026), retrieved 2026-09-25:
Standing seam metal roofs cost between $4 and $30 per square foot ... Roofing labor costs between $2 and $6 per square foot
- HomeGuide (page dated 2026), retrieved 2026-09-25:
Corrugated / standard sheet metal | $1 – $5 [material $/sq ft] | $5 – $12 [installed $/sq ft] | $500 – $1,200 [installed per square] ... The labor cost to install a metal roof is $400 to $800 per square (100 SF) on average.
- Fixr (page dated January 23, 2026), retrieved 2026-09-25:
Corrugated metal: "$3.50 – $26" per sq ft
- HomeAdvisor (page dated June 19, 2026), retrieved 2026-09-25:
Corrugated sheets: "$3.50–$15" per square foot ... Sheet metal: "$4–$6.50" per square foot
Panel counts are geometry; confirm with your supplier's panel layout. Written by the Thomas Town Digital editorial team. We match homeowners with roofers; we do not roof.
Metal roof calculator questions
How many metal roof panels do I need?
Divide each roof plane's eave length by the panel's coverage width and round up. A 36-inch coverage R-panel on a 52 ft eave needs 18 panels per side; 16-inch standing seam needs 39.
How long should metal roof panels be?
The eave-to-ridge length along the slope: half the span plus the overhang, times the pitch factor. On a 40 ft wide house at 6/12 with a 12-inch overhang that is about 23.5 ft.
How wide are metal roof panels?
McElroy Metal's R-Panel covers 36 inches. Its Maxima standing seam comes in 12, 16 and 18 inch widths (18 and 24 inch for the 3-inch leg). Check the product you are pricing.
How much does a metal roof cost per square?
Installed, standing seam is $900 to $1,600 per square and exposed-fastener panel $500 to $1,300, before tear-off (about $100 to $300 per square for one layer).