EPDM Roof Cost Calculator

How the estimate is worked out

The tool prices EPDM by the square foot of roof, the way bids are written. It starts with the installed rate for a standard job, splits it into materials and labor, and then adds separate lines for anything beyond a standard job.

• Materials = roof area x $2 to $5 (rubber, about 2 in of polyiso, adhesive, flashings)
• Labor = roof area x $2 to $5.50, times a state wage factor if you enter a ZIP
• Penetrations = (materials + labor) x 20 to 30% x (drains, pipes and curbs / squares), capped at the full premium
• Tear-off = roof area x $1 to $1.50 per layer
• Energy-code polyiso or tapered board = roof area x $2 to $4
• Cost per square = total / (roof area / 100)

Thickness, color and attachment don't get their own lines. They move the price inside the materials and labor ranges, which the next sections explain.

A worked example: a 40 by 30 garage roof

The default inputs are a 40 x 30 ft roof, which is 1,200 sq ft or 12 squares. It has 60-mil black EPDM, fully adhered over about 2 inches of polyiso, with 1 old layer torn off, 3 pipes and curbs and 1 drain.

Materials come to 1,200 x $2 to $5 = $2,400 to $6,000. Labor at the national average is $2,400 to $6,600. The 4 penetrations on 12 squares earn 33% of the busy-roof premium, which adds $320 to $1,260. Tear-off adds $1,200 to $1,800.

The total is $6,320 to $15,660, or $5.27 to $13.05 a square foot. With no penetrations it would be $6,000 to $14,400, the same figure the flat roof calculator gives for this roof.

How much does an EPDM roof cost per square foot?

A standard EPDM job runs $4 to $10.50 a square foot before tear-off, or $400 to $1,050 a square. Add one layer of tear-off and it is $5 to $12 a foot.

That $5 to $12 is the figure in our EPDM roofing guide, which counts tear-off, insulation and the membrane together. This tool lists tear-off on its own line so you can price a job with no tear-off or with two layers. The rubber itself is only about $0.80 to $2.50 a foot. Labor, adhesive, flashings and insulation make up the rest.

Thickness, color and attachment move the price inside the range

The EPDM guide says thickness and attachment method move the price within its range but doesn't give a figure for each. So the tool narrows the range instead of adding a fixed amount.

• 45 mil uses the lower half of the range. It is the entry-level grade and the easiest to puncture.
• 60 mil uses the whole range. It is the standard for houses and what most bids assume.
• 90 mil uses the upper half. The sheet costs more and is heavier to handle, so both materials and labor go up.
• White uses the upper half of materials. The guide says it costs considerably more than black.
• Ballasted uses the lower half of labor. Loose-laid rubber under rock is the fastest method to install.

Fully adhered and mechanically fastened roofs price the same here. Glue gives the best wind resistance, while screws suit decks that can't take ballast or weather too cold for adhesive.

Tear-off, insulation and penetrations add their own lines

Tear-off costs $1 to $1.50 a square foot per layer, from the flat roof guide. Heavy gravel roofs and soaked insulation cost more to haul. If you pick no tear-off, the new roof goes over the old one, which code allows only once.

Thicker polyiso to meet energy code adds $2 to $4 a foot, and tapered board for drainage adds about the same. Choosing no insulation takes about $1.40 a foot off materials, since the EPDM guide puts polyiso at roughly $0.70 an inch.

A roof crowded with skylights, HVAC units and pipes costs 20 to 30 percent more, almost all of it flashing labor. The tool gives the full premium at one penetration per square and a share below that. Rotten decking is extra at $80 to $120 a sheet.

Your ZIP code adjusts the labor

Entering a ZIP scales only the labor line, using the state's average roofer wage against the national average from the Bureau of Labor Statistics (May 2025). The factor is capped between 0.75 and 1.35. The roof cost calculator uses the same adjustment.

TPO or PVC can beat EPDM on some roofs

EPDM is the cheaper, proven choice for a simple flat roof in a cold climate. Other systems fit some jobs better.

• Hot, sunny climate. White TPO reflects heat and has welded seams, at about $6.50 to $11 a foot before tear-off.
• Grease or oil on the roof. Kitchen exhaust makes EPDM swell and soften, so use PVC.
• Regular foot traffic. A multi-ply modified bitumen roof holds up best. See TPO vs modified bitumen.
• Lots of skylights and vents. Taped flashing details take more labor than welded ones, so a crowded roof favors TPO or PVC.

To price TPO and PVC on the same roof, with rolls, seams and fasteners, use the flat roof calculator.