TPO (thermoplastic polyolefin) is a single-ply white roofing membrane for flat and low-slope roofs. Its seams are heat-welded and its white surface reflects sunlight, keeping buildings cooler. Installed TPO costs about $9–$14 per sq ft in New York City and typically lasts 20–30 years. It's best for larger flat roofs and anyone who wants lower cooling costs.
Key takeaways
- TPO is a white, heat-welded single-ply membrane for flat roofs.
- Costs about $9–$14 per sq ft installed in NYC; lasts 20–30 years.
- Reflective surface helps meet NYC cool-roof requirements and lowers top-floor heat.
- Installation quality matters more than brand: seam welding is everything.
In this guide
What is TPO roofing?
TPO stands for thermoplastic polyolefin, a single-ply membrane made from a blend of polypropylene and ethylene-propylene rubber, reinforced with a polyester scrim. It comes in rolls, usually white, and is fastened or adhered over insulation on flat and low-slope roofs.
What makes TPO different is the seams. Instead of glue or tape, the overlapping edges are welded together with hot air. A properly welded seam is as strong as the membrane itself, which is why TPO roofs resist the seam failures that cause so many flat roof leaks.
Pros and cons of TPO
Pros
- Energy efficient. The white, reflective surface keeps roofs and top floors cooler and reduces air-conditioning load.
- Strong seams. Heat-welded seams are tougher than glued or taped seams.
- Cool-roof compliant. Meets NYC's reflective roof requirement for most low-slope roofs.
- Good value. Usually cheaper than PVC with similar benefits for most buildings.
- Resists punctures and tears better than many single-ply alternatives.
- Recyclable at the end of its life.
Cons
- Installation-sensitive. Bad welds are the main way TPO fails, so the installer matters more than the brand.
- Costs more than EPDM upfront.
- Not ideal for grease or chemicals. For restaurant exhaust areas, PVC is better.
- Can be slippery when wet or frosty; walkway pads help on roofs people use.
How much does TPO roofing cost?
In New York City, installed TPO typically runs $9–$14 per square foot, about $9,000–$14,000 for a 1,000 sq ft roof. What moves the price:
- Tear-off: removing one or more old layers
- Insulation: amount and type, and tapered insulation to fix ponding
- Membrane thickness: thicker membranes cost more and last longer
- Penetrations and details: vents, HVAC curbs, parapets and skylights
- Access and borough: Manhattan and Brooklyn cost more than Staten Island and Queens
See how TPO compares on cost with other materials in our NYC roof cost guide, or use the calculator there.
TPO vs. other flat roof systems
| TPO | EPDM | PVC | Modified bitumen | |
|---|---|---|---|---|
| Installed cost (NYC) | $9–$14/sq ft | $8–$12/sq ft | $10–$16/sq ft | $9–$13/sq ft |
| Lifespan | 20–30 yrs | 20–30 yrs | 25–35 yrs | 20–30 yrs |
| Color | White (reflective) | Usually black | White | Granulated / coated |
| Seams | Heat-welded | Adhesive / tape | Heat-welded | Torched / adhered |
| Best for | Energy savings, larger roofs | Budget, row homes | Restaurants, chemicals | Foot traffic |
TPO vs. EPDM: EPDM is cheaper and extremely flexible in cold weather, but it's dark (absorbs heat) and its glued seams are the weak point. TPO costs a little more and reflects heat.
TPO vs. PVC: Both are white and heat-welded. PVC resists grease, oils and chemicals better and is more fire-resistant, at a higher price. For most buildings, TPO is the better value.
TPO vs. modified bitumen: Mod-bit is multi-ply and very tough under foot traffic, but heavier and not as reflective unless coated. TPO is lighter and cooler.
How a TPO roof is installed
- Tear-off and deck inspection. Old roofing removed, damaged decking replaced.
- Insulation. Rigid insulation boards, often tapered so water flows to drains.
- Membrane. TPO sheets mechanically fastened or fully adhered.
- Seam welding. Overlaps welded with a hot-air welder and probe-tested.
- Flashing. Walls, parapets, curbs and pipes flashed with TPO details.
- Edges and drains. Edge metal, drains and scuppers completed and sealed.
How long does TPO last, and how to make it last longer
A well-installed TPO roof typically lasts 20–30 years. To get there: keep drains and scuppers clear, inspect twice a year, add walkway pads around equipment, and repair punctures quickly. The most common cause of early TPO failure we see is not the membrane. It's poorly welded seams and flashing details from the original install.
Is TPO right for your building?
Good fit: commercial and mixed-use flat roofs, larger row-home roofs, top-floor apartments that get hot, buildings planning solar, and anyone who needs to meet NYC cool-roof rules.
Consider something else: restaurant roofs with grease exhaust (PVC), roofs with heavy foot traffic (modified bitumen), or tight budgets on small row-home roofs (EPDM).
We install TPO across Staten Island, Brooklyn, Manhattan and Queens. See our flat roofing services, Brooklyn flat roofing and commercial roof replacement.
Frequently asked questions
What is a TPO roof?
A single-ply roofing membrane made from thermoplastic polyolefin, usually white, used on flat and low-slope roofs. Its seams are welded with hot air, so the seams become one continuous sheet.
How much does a TPO roof cost?
In New York City, installed TPO typically costs $9–$14 per square foot, or about $9,000–$14,000 for a 1,000 sq ft roof, depending on tear-off, insulation, thickness and access.
How long does a TPO roof last?
Typically 20–30 years with proper installation and maintenance. Thicker membranes, good drainage and twice-yearly inspections help it reach the top of that range.
Is TPO better than EPDM?
Neither is better everywhere. TPO is more reflective and has welded seams; EPDM is cheaper, very flexible in the cold and easy to repair. For energy savings and larger roofs we usually recommend TPO; for budget-conscious row-home roofs, EPDM.
Can TPO be installed over an existing roof?
Sometimes, if there's only one existing layer and the insulation underneath is dry. Otherwise a tear-off is the better investment.
Does a TPO roof need maintenance?
Yes, but not much: inspect it twice a year, keep drains clear, check seams and flashing, and repair any punctures from foot traffic or HVAC work promptly.
