EPDM Roofing Calculator

Material quantities for EPDM single-ply roofing.

Roof Length (ft)

Roof Width (ft)

Membrane Thickness (mil)

Sheet Width (ft)

Attachment (0=Adhered, 1=Mech, 2=Ballast)

Waste Factor (%)

Tab to move between fields

Roof Area (sqft)

3,200

Membrane Needed (sqft)4,050

Number of Sheets5

Seam Tape Rolls4

Termination Bar (pcs)24

Bonding Adhesive (gal)55

Lap Sealant Tubes19

Est. Material Cost ($)$5,463.00

How to Use This Calculator

Enter roof dimensions (length x width in feet) and select membrane thickness (mil).
Set sheet width (ft) and select attachment method (adhered, mechanically fastened, or ballasted).
Review calculated roof area, membrane sqft, number of sheets, and seam tape rolls.
Add fastener count for mechanically attached or ballast weight for ballasted systems.
Include splice adhesive and lap sealant quantities in your material order.

How the result changes with Roof Length (ft)

Roof Length (ft): Length of the roof area in feet.
Roof Width (ft): Width of the roof area in feet.
Membrane Thickness (mil): EPDM membrane thickness. 45 mil = standard, 60 mil = premium/longer life.
Sheet Width (ft): Width of EPDM rolls. Common sizes: 10 ft, 20 ft.
Attachment (0=Adhered, 1=Mech, 2=Ballast): 0 = fully adhered (adhesive), 1 = mechanically fastened, 2 = ballasted (gravel).
Waste Factor (%): Extra material for overlaps, cuts, and waste.

Roof Area (sqft): Total roof area to be covered.
Membrane Needed (sqft): Total EPDM membrane including overlaps and waste.
Number of Sheets: Number of membrane sheets/rolls required.
Seam Tape Rolls: Rolls of seam tape for sheet-to-sheet laps (100 ft/roll).
Termination Bar (pcs): 10 ft termination bar pieces for perimeter edge.
Bonding Adhesive (gal): Gallons of bonding adhesive (fully adhered systems only).
Lap Sealant Tubes: Tubes of lap sealant for seams and perimeter.
Est. Material Cost ($): Approximate material cost (labor not included).

Identify Input Parameters
4 parameters
Roof Length (ft) = 80, Roof Width (ft) = 40, Membrane Thickness (mil) = 60, Sheet Width (ft) = 10 = 6 input(s) provided
Calculate Roof Area
Roof Area = roofLength * roofWidth
3200 = 3200
Calculate Membrane Needed
Membrane Needed = numSheets * sheetWidth * sheetLengthFt
4050 = 4050
Calculate Number of Sheets
Number of Sheets
5 = 5