Contractor Calculator · Metal Roofing
Metal Roof Cost Calculator: Panels, Trim, Material
Give it a footprint and a pitch. It returns squares, panel count, trim feet, underlayment, screws, and a sourced price band.
Need the customer number? Estimate it from a photo in about 6 seconds.
Squares, panels, trim, and material
Custom rise below.
Price band is two brands at one retailer, Sutherlands, for 29 gauge exposed fastener panel at 36 in coverage, read September 14, 2026, local prices vary. Switch to standing seam or metal shingle and the price fields clear, because no seller publishes a price we can stand behind. Trim, screws and labor stay quantities.
How the metal roof calculator sizes the job
Metal is ordered by the square, and a square is 100 square feet of finished roof. The footprint on the ground is not that number, because the roof leans. Two steps fix it: turn the footprint into real roof area, then divide by panel coverage.
Coverage width is what a panel protects once the side lap is buried, not the sheet width. The Nu-Mag panel priced below is 38 in wide and covers 36 in.
The slope factor is the whole trick
Pitch is written as rise in 12. A 6 in 12 roof climbs 6 in for every 12 in of run. One foot of ground then carries 13.42 in of roof, the square root of 6 squared plus 12 squared. Divide by 12 for the slope factor, 1.118.
It multiplies the footprint, never an area you measured on the deck. That is why entering squares turns the pitch step off.
| Pitch | Slope factor | 1,200 sq ft footprint becomes |
|---|---|---|
| 4 in 12 | 1.054 | 1,264.9 sq ft |
| 6 in 12 | 1.118 | 1,341.6 sq ft |
| 8 in 12 | 1.202 | 1,442.2 sq ft |
| 12 in 12 | 1.414 | 1,697.1 sq ft |
Worked example: 40 by 30 at 6 in 12
The footprint is 1,200 sq ft. At 1.118 the roof is 1,341.64 sq ft, or 13.42 squares. Add 10 percent waste and you buy 1,475.8 sq ft of panel. At 36 in coverage that is 492 lineal feet.
Slope length is 15 ft of half span times 1.118, or 16.77 ft. Panels cut at 17 ft and it takes 29. Underlayment takes 2 rolls and screws come to 1,230.
SimplyWise Cost Estimator turns the same job into a priced estimate from one photo.
What the material runs
A 29 gauge exposed fastener panel at 36 in coverage listed at $4.69 a lineal foot. A second brand listed $4.99 on September 14, 2026. That is $1.56 to $1.66 per square foot, the band the calculator loads.
We hold no published seller price for standing seam or stone coated shingle. The calculator will not take a multiplier off the cheap panel and print it as a price. Type your own number in.
Labor is deliberately absent. Rates swing by market, pitch, tear off and access, and no published figure clears our sourcing bar.
Turn the take off into a quote
SimplyWise Cost Estimator turns a photo into an itemized estimate in about 6 seconds, with material and labor line items. Pricing is $29.99/mo or $239.99/yr, about $20/mo on annual, with a 7-day free trial.
Trim, underlayment and screws
Trim is bought by the foot. Measure ridge and hip, valley, eave and rake separately.
Synthetic underlayment sells in 4 ft by 250 ft rolls, 1,000 sq ft before lap. Screws follow the fastener table. Use 4.5 per lineal foot at 12 in spacing, 3.0 at 18 in, 2.5 at 24 in.
Order a metal roof in this sequence
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Measure the footprint, not the roof
Length and width on the ground, plus overhangs.
-
Apply the slope factor
Square root of rise squared plus 144, over 12, times the footprint.
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Add waste before you divide
Ten percent on a gable, more on hips and valleys.
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Count trim and fasteners separately
Ridge, valley, eave and rake by the foot.
Sources
Panel and underlayment prices
- Sutherlands, Metal Sales 22934 Classic Rib, per foot ($4.69 a lineal foot, read 2026-09-14).
- Sutherlands, Nu-Mag panel, per linear foot ($4.99 a lineal foot, 36 in coverage on the listing, read 2026-09-14).
- Sutherlands, StarWrap synthetic underlayment, 4 ft by 250 ft ($74.99 a roll, 1,000 sq ft, read 2026-09-14).
Coverage widths and fastener spacing
- McElroy Metal, MM101 catalog (Max-Rib 36 in cover, Modern-Rib 12 in, Medallion-Lok 12, 16, 18 in, Tilcor CF Shingle 49 5/8 in; read 2026-09-14).
- Union Corrugating, 5 Rib installation guide (screws per lineal foot 4.5 at 12 in, 3.0 at 18 in, 2.5 at 24 in; read 2026-09-14).
- Metal Sales, PBR panel manual (36 in coverage in the data table; read 2026-09-14).
Product
- SimplyWise Cost Estimator, App Store (4.8 rating; verified 2026-09-09).
Common questions on metal roof material
Sizing the roof
How do I calculate metal roof squares?
Multiply the footprint by the slope factor, then divide by 100. A 1,200 sq ft footprint at 6 in 12 is 1,341.64 sq ft, or 13.42 squares.
What is the slope factor for a 6 in 12 pitch?
1.118. It is the square root of 6 squared plus 144, divided by 12. Multiply the footprint by it, never the finished roof area.
How many metal panels do I need?
Add waste, then divide by coverage width times panel length and round up. At 36 in coverage and 17 ft panels a 13.42 square roof takes 29 panels.
Material and price
How much does metal roofing panel cost per foot?
Exposed fastener panel at 36 in coverage listed at $4.69 and $4.99 a lineal foot. Two brands at one retailer, read September 14, 2026. We hold no published seller price for standing seam.
How many screws does a metal roof take?
2.5 panel screws per lineal foot at 24 in spacing. Then 3.0 at 18 in and 4.5 at 12 in, per the manufacturer fastener table.
Can SimplyWise price a metal roof from a photo?
Yes. SimplyWise Cost Estimator turns a photo into an itemized estimate in about 6 seconds, with material and labor line items. Free to try, $29.99/mo or $239.99/yr.
Turn the metal take off into a signed quote.
Snap a photo, get an itemized estimate in about 6 seconds.