Last reviewed October 31, 2026.
The kitchen sits in the back extension, and on an August afternoon it runs noticeably hotter than the rest of the house. The old roof over it is due. One of the roofers who comes out to look suggests white TPO instead of black rubber.
Our flat roofs guide lines TPO up against EPDM, PVC and modified bitumen and lists County Roofing Systems’ residential prices. This page sticks to TPO.
What TPO is made of and the colors it comes in
Carlisle describes its Sure-Weld TPO as a heat-weldable, single-ply thermoplastic polyolefin membrane for new roofs and re-roofing, and says it contains no chlorine or plasticizers. It comes in white, gray and tan. Johns Manville sells the same three colors and notes that grey and tan may carry an upcharge on smaller projects.
Color decides how much sun bounces off. Johns Manville’s data sheet lists its white 80 mil TPO at a solar reflectance of 0.77 when new and 0.70 after three years of weathering, as rated by the Cool Roof Rating Council. NYC Renovators, which has a Valley Stream office, says white TPO is often chosen for that reflectivity.
Which Long Island roofs suit TPO
Local roofers do not reach for TPO on every flat roof. Selden’s L.I. Taylor Construction recommends it for large residential flat areas in full sun, and EPDM rubber for a small roof over an addition or garage.
NYC Renovators lists additions, garages and multifamily buildings as TPO roofs, and says it performs best on broad open areas with planned positive drainage. Roofing Time Inc. in Bellport, in its own comparison table, files TPO under energy-efficient retrofits.
Is your low-slope section small, shaded or full of corners? Read the EPDM rubber roof page before you decide.
Hot-air welded seams
TPO sheets are not glued at the laps. They are melted together. Carlisle’s system sheet says adjoining sheets are hot-air welded, and NYC Renovators describes TPO as a reinforced membrane joined with hot-air welded seams.
So the person holding the welder matters. NYC Renovators names installation quality as the critical limit of TPO. Johns Manville’s data sheet claims one of the widest melt windows, which it says promotes better welds over a wider variety of speeds and temperatures. Neither claim replaces a crew that welds TPO often.
Prices for fixing a split weld sit in our repair cost breakdown.
TPO thickness and the warranty it buys
Carlisle makes Sure-Weld in 45 and 60 mil, plus an 80 mil Sure-Weld EXTRA, in widths from 6 to 16 feet and 100-foot rolls. Johns Manville makes 45, 60 and 80 mil, and its data sheet for the 80 mil sheet lists rolls 5 to 12 feet wide.
Here thickness buys years. On a properly installed and inspected commercial project, Carlisle’s April 2023 system sheet lists:
- a 10-year Total System or 15-year Golden Seal warranty when every material is Carlisle’s
- a 20-year Golden Seal warranty with 60 mil Sure-Weld EXTRA
- a 25 or 30-year Golden Seal warranty with 80 mil Sure-Weld EXTRA
- a separate 10-year reflectivity warranty with white membrane
- puncture coverage available with 60 and 80 mil Sure-Weld EXTRA
- higher wind speed warranties, up to a 120 mph peak gust, on review by Carlisle
Before any of that is issued, Carlisle says, one of its field service representatives inspects the finished roof. Johns Manville’s October 2024 data sheet lists its 80 mil TPO for Peak Advantage guarantees of 5 to 30 years.
Both programs are written around commercial jobs. Ask whether a house extension qualifies, or whether the only coverage is the roofer’s own.
How long TPO lasts, by Long Island accounts
| Company | TPO lifespan claim |
|---|---|
| Roofing Time, Bellport | 15 to 25 years |
| L.I. Taylor, Selden | 20 to 30 years, if water drains off as designed |
| North Shore Roofing, Port Washington | 20 to 30 years (commercial guide, July 2026) |
NYC Renovators puts it bluntly that TPO is not automatically better than EPDM. Roofing Time gives rubber the longer life in that same table, a 25 to 30-plus year range.
What TPO costs on Long Island
Roofing Time’s table rates TPO’s installed cost as higher than EPDM, without giving dollars. North Shore Roofing’s July 2026 commercial guide puts TPO at $6.50 to $9.50 a square foot installed.
For house-sized flat roofs, the per-square-foot TPO ranges from County Roofing and Greene Group sit in our flat roofs guide. Commercial TPO prices from Elite Waterproofing and EZ Roofing are in our commercial roofing guide.
When the quotes land, line them up on five things: the brand, the thickness in mils, the color, whether the old roof comes off, and whether the warranty named is the manufacturer’s or the roofer’s. If the existing membrane is sound, a coating may be worth pricing too.
