TPO and EPDM are two types of roofing that specifically suited to low slope and flat roofs. Both offer reasonably priced roofing solutions so which one is better for your roofing project. That is the question we are going to answer for you now.
After explaining what each roofing type is, let’s compare TPO and EPDM in relation to the factors that matter to you like cost, longevity, installation, the environment and your climate. Let us know any other questions you may have in the comments section below. Also be sure to read our comparison of TPO Vs PVC roofing.
WHAT IS EPDM ROOFING?
Ethylene propylene diene monomer, or EPDM, is a waterproof rubber roofing with versatile usage. It comes in thickness from 45, 60, 75, and 80 mils, but most roofing contractors won’t touch material less than 60 mils thick. EPDM roofing is available in many widths from 7.5 feet to 50 foot widths. If you need to have a seam for your large roofing project, you can use a liquid adhesive or primer with seam tape. EPDM is recommended mostly for flat roofs, but this flexible single-ply roofing is also used for dome-shaped roofs and barrel roofs.
Still confused? Get the complete breakdown on EPDM roofing.
WHAT IS TPO ROOFING?
TPO roofing is also known as thermoplastic polyolefin. It is a single-ply membrane, which means it goes down in one layer of installation. However, the membrane consists of sheets of TPO fused to a middle layer of fiberglass or polyester to reinforce strength and resistance to shrinking damage.
Most pro roofing contractors recommend TPO when toughness is a high priority, even though the initial cost is higher than for EPDM. TPO comes in a variety of thicknesses, from 45 mil and up to 90 mil. The thicker the material, the longer it will last.
TPO roofing is mostly on flat roofs, but it is gaining acceptance as a residential sloped roof option. Sure, it has a very different look than asphalt shingles, metal panels and wood shakes, but it reflects UV better than most other roofing options and is competitively priced against them. Expect to see more TPO in your neighborhood if your climate is sunny and warm.
CONSTRUCTION/INSTALLATION
The installation of TPO and EPDM roofing is very similar, and hiring a professional with a lot of experience working with the materials you choose is recommended. One major difference is that most roofs will have one or more seams when TPO is installed. Many EPDM roofs are seamless due to the wider manufactured widths.
Yes, experienced contractors will be more expensive, but the quality and the workmanship will be worth the added costs when the material holds fast to the roof and seams don’t come apart. TPO installation will take no more than a few days on most roofs. For EPDM roof installation on a similar roof, including prep work and sealing the seams, generally takes twice as long. In short, the cost of TPO roofing has more to do with advantages in the quality of the material. The price of EPDM is largely based on increased labor charges.
COST
TPO and EPDM roofing cost-effective roofing solutions. Plan on spending between $5.00 and $9.00 per square foot for an installed EPDM roof. Within the range, cost rises as material thickness increases, as you’d expect. Site factors in terms of the complexity of the roof affect cost too – true for TPO also. TPO roofing is a little more expensive to install, ranging from $6.50 to $12.00 per square foot for materials and the labor with an average of $7.50 to $9.00 per sq/ft.
What about ongoing maintenance costs? Property owners will tell you that while an EPDM roof costs a few bucks less, the maintenance costs are higher – which might push the lifetime cost of this material beyond that of TPO. If you’ve got the long-term in view, don’t decide based on initial cost alone. Read more about TPO roofing cost.
LIFESPAN/DURABILITY
The lifespan of TPO and EPDM roofing varies depending on the thickness of material and where you live. As is true with any roofing material, harsher environments cause either material to age faster, so the time for replacement comes more quickly. EPDM roofs generally have at least a 20-year warranty.
With proper upkeep and care, you can expect your EPDM roof to last up to 30 years. The upkeep mainly consists of resealing the seams and repairing cracks or punctures in the material. It should be inspected at least every quarter and after storms with large hail or wind-driven debris. These maintenance practices are what drive up the lifetime cost beyond that for TPO.
The best TPO brands have a warranty of 20 years or more. Here’s a potential concern though: TPO is a relatively new roofing product, especially the new-and-improved formulations, and there isn’t much of a track record on durability. Experienced contractors expect that the upgrades in materials – and when the roof is properly maintained – homeowners can expect a TPO roof to last between 18-25 years before a replacement will be necessary.
ENVIRONMENTAL CONSIDERATIONS
The production of TPO and EPDM are less harmful to the environment than asphalt roofing. EPDM roofing is made mostly from recycled materials, a large reason manufacturing the roofing material requires less energy than most other forms. And it is recyclable at the end of its useful life on your roof. TPO contains varying amounts of recycled material, depending on the brand, and it is recyclable.
TPO’s other claim to ecofriendliness is its reflective quality. Most TPO roofing is white or tan and has a high solar reflectance rating, which is estimated to reduce energy used directly related to heat penetration by 30% compared to asphalt roofing. Also, since EPDM roofing is usually black, it can really absorb the heat. This will cause poorly insulated buildings to warm up, which might be a bonus in winter but increases air conditioning costs in warm weather.
CLIMATE CONSIDERATIONS
TPO is a better choice in sunny climates, as noted. EPDM roofing is prone to shrinking in consistent sun exposure, and the seams can separate and material pulls away from the roof edge – and when it does rain, leaks result. TPO roofing is much better at handling prolonged sun exposure than EPDM roofing. But it isn’t perfect. TPO doesn’t respond as well to hot/cold cycles that cause the material to repeatedly expand and shrink. The cycles might eventually cause small cracks in the roofing material, and leaks will follow.
EPDM VS TPO – WHICH IS BETTER?
If you need a replacement roof, you already understand that EPDM and TPO are good options. Which is better?
Here are a couple key considerations when deciding.
TPO is a better choice in hot, sunny areas and where large hail and wind-driven debris are part of the yearly weather. It is worth paying more upfront for a material that, in a calm and cloudy climate, doesn’t last as long. Choose EPDM in an area frequented by brutal storms, and the “30-year potential lifespan” might become 12-15.
As noted, in regions with freeze/thaw cycles throughout the year, and the contraction/expansion that results, you’ll get the 20-30 years you expect from EPDM. A TPO roof might give you the low end of its range, roughly 15-18 years, and your higher upfront investment will be wasted.
And remember, an experienced roofing company will likely lead to a better installation process and a longer-lasting roof.
Jamie Sandford is the Chief Editor at RenoCompare (