TPO Roofing Calculator

Membrane area, adhesive, and accessories for TPO system.

Roof Length (ft)

Roof Width (ft)

Membrane Thickness (mil)

Roll Width (ft)

Roof Penetrations

Waste Factor (%)

Tab to move between fields

Roof Area (sqft)

7,200

Membrane Needed (sqft)8,435

Number of Rolls7

Seam Length (LF)720

Fasteners + Plates4,416

Termination Bar (pcs)36

Edge Metal (pcs)36

Est. Material Cost ($)$6,655.00

Roof Area With Waste7,776

How to Use This Calculator

Enter roof dimensions (length x width in feet), membrane thickness (mil), and roll width (ft).
Enter the number of penetrations.
Review roof area, membrane sqft, number of rolls, total seam length (LF), and fasteners.
Include cover board if required by the specification -- TPO directly over insulation may reduce warranty.
TPO seams are heat-welded -- seam quality is critical and requires an approved weld tester for QC.

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): TPO thickness: 45 mil (budget), 60 mil (standard), 80 mil (premium).
Roll Width (ft): TPO roll width. Common: 6 ft, 8 ft, 10 ft, 12 ft.
Roof Penetrations: Number of pipes, vents, and HVAC curbs requiring flashing.
Waste Factor (%): Extra material for overlaps, cuts, and waste.

Roof Area (sqft): Total flat roof area.
Membrane Needed (sqft): Total TPO membrane including overlaps and waste.
Number of Rolls: TPO membrane rolls required.
Seam Length (LF): Total linear feet of hot-air welded seams.
Fasteners + Plates: Mechanical fasteners with stress plates (field + perimeter + corners).
Termination Bar (pcs): 10 ft termination bar pieces for perimeter.
Edge Metal (pcs): 10 ft TPO-coated edge metal pieces.
Est. Material Cost ($): Approximate material cost (labor not included).

Identify Input Parameters
4 parameters
Roof Length (ft) = 120, Roof Width (ft) = 60, Membrane Thickness (mil) = 60, Roll Width (ft) = 10 = 6 input(s) provided
Calculate Roof Area
Roof Area = roofLength * roofWidth
7200 = 7200
Calculate Membrane Needed
Membrane Needed = numRolls * rollWidth * (roofLength + 0.5)
8435 = 8435
Calculate Number of Rolls
Number of Rolls
7 = 7