Single-Ply, Simplified: TPO vs. PVC vs. EPDM
Updated: Sep 16
Single-ply roofing is exactly what the name suggests: one membrane layer (or ply) used to waterproof a low-slope roof.
The three main types you'll see on commercial roofs are TPO, PVC, and EPDM. They all do the same basic job, but they each perform a little differently. And there are good reasons to choose one over another depending on the job.
Here's how the three compare.
TPO (Thermoplastic Polyolefin)
Reliable & Cost-Effective
TPO is the most widely installed single-ply membrane in North America today, and for good reason. Its cost, durability, reflectivity, and installation options make it a practical choice for a lot of straightforward commercial roofing projects.
TPO is a thermoplastic membrane, which means it softens when heated and hardens when cooled. As a thermoplastic, the membrane can be heat-welded at the seams. Sheets are rolled out and the laps are welded together with hot air to create a continuous waterproof membrane across the roof.
White is the most common color, but grey and tan are also available. White TPO has high solar reflectivity, which can help reduce rooftop surface temperatures and cooling loads depending on the building and climate.
TPO also gives you quite a few installation options. It can be mechanically fastened, adhered, self-adhered, or induction welded, with the majority of systems being mechanically fastened for greater cost effectiveness. Compared to EPDM (which we'll cover later), TPO membranes are more rigid, which may also help you achieve greater wind uplift performance, especially with fastened systems.
Best Suited For: Warehouses, distribution centers, big-box stores, strip malls, and any buildings with a large footprint where budget is a priority; and roofs with high wind uplift requirements.
Keep in Mind: TPO isn't typically our go-to for roofs exposed to grease, oils, fuels, or certain chemicals. (Spoiler: Check out PVC instead.) Installation requires hot-air welding equipment and a crew that knows how to weld and detail it properly.
PVC (Polyvinyl Chloride)
Excellent Chemical Resistance
If you have grease, oil, fuel, or certain chemical exposure on the roof, PVC should usually be one of the first membranes you look at.
Like TPO, PVC is a thermoplastic, so its seams are heat-welded. The membrane tends to be more flexible than TPO (due to plasticizers) and has a wider welding-temperature window, which can make complex flashings a little easier.
Chemical resistance is one of the main reasons to use PVC. It holds up well around many of the exposures that can be tough on other roofing membranes. That's why you see it used so often on restaurants, airports, manufacturing facilities, and similar buildings.
PVC is also fire-retardant and self-extinguishing, which is why it’s frequently used at airports, where it can withstand jet fuel exposure without breaking down.
Best Suited For: Restaurants, food and beverage processing facilities, manufacturing facilities, airports, stadiums, and roofs where chemical or grease exposure is a concern.
Keep in Mind: Higher material cost than TPO. Not intended for ballasted systems. Like TPO, PVC requires specialized equipment and trained crews for installation.
EPDM (Ethylene Propylene Diene Monomer)
Rubber Roofing
EPDM has been around for decades. It’s a synthetic rubber membrane that stays flexible through a wide range of temperatures and accommodates a good amount of movement. Because EPDM stays flexible through temperature changes, it has a long history of use in colder climates and on large roofs where the membrane sees a lot of expansion and contraction.
Installation is a little different from TPO and PVC. EPDM is a thermoset material, so the seams aren't heat-welded; they're joined with adhesive or seam tape. Factory-applied seam tape is available on some membranes and can save quite a bit of labor in the field.
Johns Manville offers black and white EPDM, with reinforced and nonreinforced options available depending on the system. JM also extrudes its EPDM membrane rather than calendaring it, which produces a uniform membrane surface and thickness, making seam and flashing preparation easier in the field.
EPDM can also be used in ballasted systems, something you can't do with JM TPO or PVC.
Best Suited For: Large commercial and industrial roofs, northern climates, and projects where you want flexibility and durability.
Keep in Mind: Black EPDM absorbs more solar heat than white EPDM. Also, EPDM isn't ideal where rooftop exhaust contains oils (they affect the rubber chemistry).
At a Glance: Side-by-Side Comparison
TPO | PVC | EPDM | |
Material | Thermoplastic | Thermoplastic | Synthetic rubber / thermoset |
Installation Methods |
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Colors Available through JM |
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*Energy Savings membranes Not all colors are available as standard stocked items in all size configurations. |
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Ideal Applications | Warehouses, big box stores, strip malls | Airports, restaurants, manufacturing plants | Large footprints, northern climates |
One thing to remember: you're choosing a roof system, not just a membrane.
Two roofs using the same membrane can have completely different systems. The insulation, cover board, attachment method, deck, flashing details, installation quality, and maintenance will all affect how your roof performs.
So, which one is right for your project?
For a large, straightforward commercial roof with no unusual chemical exposure, TPO is often a good place to start.
If there are kitchens, grease, oils, fuels, or industrial pollutants, take a look at PVC.
And if you're looking at a large roof where flexibility or a ballasted installation is important, EPDM may make sense.
Of course, those are just starting points. There are plenty of exceptions. Roof geometry, wind design, deck type, attachment method, existing conditions, warranty requirements, and budget can all change the recommendation.
Need help deciding?
BRT represents Johns Manville's full commercial roofing lineup, including TPO, PVC, EPDM, modified bitumen (SBS and APP), built-up roofing (BUR), and liquid-applied roofing (PMMA).
If you're working through a spec or trying to narrow down the right system for a building, give us a call and we'll help you find the right fit.
