3 Best Types of Roof Membranes for Low Slope Roofing

Do you need to replace your low slope roof? Are you trying to find the right membrane for your low slope roof replacement?

Unfortunately, this low slope roofing removes asphalt shingles out of the equation. Low slope roofing needs a waterproof material, which is why membranes are the go to.

However, there plenty of options, and not all of them are a good choice for residential roofing.

For over 35 years, Bill Ragan Roofing has helped homeowners make the best purchasing decision for their roofing needs. Because low slope roofing is so unique, I'll break down the 3 best types of membrane roof systems for residential roofing. 

By the end of this article, you'll learn:

• 3 best types of roof membranes for low slope roofing

• How much does a membrane roof cost?
• Why does a low slope roof need a membrane roof system instead of asphalt shingles?
  

3 best types of roof membranes for low slope roofing

While there are different types of membranes or low slope roofing materials, there are three that I specifically recommend for residential roofing purposes. And honestly, they're all great options. 

You just need to choose the right one for your situation.

1. TPO roofing membrane

TPO roofing (thermoplastic polyolefin) is a single-ply white membrane used in commercial and residential roofing. Because a TPO roofing membrane is white, it reflects heat instead of absorbing it. 

This makes TPO a great option for a flat roof over a bedroom because it’ll keep the room below cooler. Of course, you can still use it over a non-living space like a garage or covered patio. 

No matter where the TPO roofing membrane is installed, it’s important to consider the look of a white membrane. The white will get noticeably dirty over time, so you need to determine if seeing it from a window is a big deal. 

If you can't see the roof, you won’t have to worry about this. But it’s just something to keep in mind when making your final decision.

Just know the “dirtiness” doesn’t affect the functionality of the membrane. As long as your TPO roofing membrane is installed properly, you can expect to get around 25 years out of it. 

2. PVC roofing membrane

PVC roofing (polyvinyl chloride) is a single-ply white membrane used in both commercial and residential roofing. Like TPO, the white membrane reflects heat instead of absorbing it.

Besides their chemical makeup, a PVC roofing membrane has very similar characteristics to a TPO roofing membrane. The installation process for both is even pretty much the same. 

The only real difference is that PVC roofing is more flexible and has been around longer than TPO roofing. Just like TPO, a PVC roofing membrane is a great option for a flat roof over a living space because it’ll keep the room below cooler.

But you’ll also have to consider how dirty the white will get when seeing it from the window. Remember, it will have no impact on the functionality of the membrane roof. 

You can expect to get around 25 years out of a PVC roofing membrane as long as it’s installed properly.

3. EPDM roofing membrane

EPDM roofing (ethylene propylene diene terpolymer) is a synthetic rubber black membrane mostly used in commercial and medical facilities. However, EPDM roofing has its place in residential roofing and is becoming more popular.

Because an EPDM roofing membrane is black, it’ll absorb heat instead of reflecting it like the white membranes. For this reason, I wouldn’t recommend using it over a bedroom or living space. 

While it doesn’t have the advantage of reflecting heat like a white membrane, you don’t have to worry about it getting as dirty. So, you don’t have to necessarily worry about the aesthetic of an EPDM roofing membrane if it can be seen from a window. 

EPDM is recommended for a flat roof over a garage or a non-living space, but it can still be installed over a bedroom or living roof. Just make sure to consider the heat absorption of the black EPDM membrane roof system when making your final decision.

EPDM roofing membranes are extremely durable, and we like to say it’s like having a bulletproof rubber roof system. Because of this, you can expect to get around 25 to 30 years out of a fully adhered 0.060 thickness EPDM roof.

How much does a membrane roof cost?

Including labor and materials, a membrane roof system on a flat roof will cost around $12.00 to $17.00 per square foot in 2026. Obviously, the size of the roof determines where you'll fit in the price range. 

However, the cost per square foot will trend towards the higher end of the price range on smaller projects. This is because roofing membranes come in rolls, so smaller roofs require more cutting, fitting, and other finer details to prevent leaks. 

With that in mind, the table below gives you a better idea of membrane roofing's cost based on the area's square footage. 

Just keep in mind that it’s impossible to give you an exact price due to all the different cost factors. The membrane you choose, roofing contractor you hire, and your area's supplier prices play a huge role in the cost, but there's much more.

Labor costs

Labor costs are factored into every line item on an estimate. So, if anything takes time and labor, it adds to the labor costs of a flat roof replacement. 

Unfortunately, there’s no set price for labor and time because it depends on the roofing contractor you hire. But the more manpower and time it takes to replace your roof, the higher the cost.

Square footage of the roof

As I've already mentioned, the square footage of the roof plays a huge role in a flat roof replacement's cost. It affects the amount of materials used, labor, and time needed to complete the job. 

I say square footage because it’s what homeowners are familiar with. However, you’ll also hear a roofing contractor say “price per roofing square” (100 square feet).

Residential or commercial project

While it plays into square footage, whether the roof is residential or commercial can affect a flat roof replacement's cost. Remember, the cost per square foot will trend towards the higher end of the price range on smaller projects. 

So, commercial roofs actually end up being cheaper per square foot than residential roofs. This doesn't mean it'll be cheaper overall, but residential roofs are more complex and require more attention to detail that usually increase labor costs.

Insulation type used

A big cost factor is the type of insulation and amount being installed under the roofing membrane. Insulation that’s thick enough to insulate the entire structure costs more than using fabric insulation and gluing the membrane to it.

The other components of a the membrane roof system

Another thing that always factors into pricing is the other components that are included with a membrane roof system. While it'll be all wrapped into one price, the specific costs of the components depends on how the membrane roof system is being installed.

Tearing off and dump fees

During the tear-off process, the old roof and other components are ripped up until there's only a clean roof deck. So, there will be a labor cost associated with tearing off the old roof. 

However, the torn off debris also must be loaded into a dump truck or trailer to be taken to a dump of the contractor’s choice. The dumpsites charge significant fees for this service, so there will also be a dump fee and labor cost for the crew member(s) doing the work. 

Roof penetrations

A roof penetration is anything that comes through your roof, like plumbing vents, gas vents, kitchen/bathroom vents, skylights, and chimneys. The more penetrations your roof has, the more it impacts the cost. 

This is especially true for flat roofing, which doesn't have enough pitch to drain. Smaller pipes or vents won’t impact much, but skylights and chimneys add more to a new roof’s cost because they take longer to flash and work around. 

Why does a low slope roof need a membrane roof system instead of asphalt shingles?

Any roof or a roof facet is considered low slope when the pitch (aka steepness) is below a 2:12 (less than 2 vertical units up for every 12 horizontal units out). Because the slope won't allow for normal water drainage, there needs to be a waterproof material. 

Because asphalt shingles aren’t meant to have sitting water on them, the shingle manufacturer’s installation instructions and building codes state you can’t install asphalt shingles on a roof with a pitch below 2:12. This is why a membrane (or metal) roof system has to be installed to prevent leaks from coming into the space below a low slope or flat roof. 

If a roofing contractor even mentions putting shingles on a low slope roof, don’t go with them.

How do you find a reputable roofer for your low slope roofing project?

After reading this article, you should have an idea which one of the low slope membranes are right for you. There are other options, like modified bitumen.

However, these are the three I recommend for low slope roofing on a residential home. However, low slope roofing is specialized and unique, so you need to hire a great roofer with the right experience. 

This is a crucial decision that you can’t take lightly, especially when it comes to waterproofing. That’s why I wrote another article with the 9 tips you need to hire a great roofing contractor for your low slope roofing project. 

Check out 9 Tips for Hiring a Great Roofing Contractor to avoid making the wrong hiring decision for your low slope roofing project.