5 Best Flat Roofing Materials (Compared)

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5 Best Flat Roofing Materials (Compared) 2

There are many advantages to having a flat roof. Not only are these roofs considered the more modern option, but they’re more cost-effective to install and maintain. However, when it comes down to flat roofs, you might be wondering about the best materials to use.

In terms of single-ply flat roofing materials, PVC (polyvinyl chloride), TPO (thermoplastic polyolefin), EPDM (ethylene propylene diene terpolymer), and MB (modified bitumen) are the best choices. Built-up roofs (BUR) use a layered approach and combine different layers of material with asphalt.

In this article, we’ll break down the advantages of having a flat roof, the best materials to use for flat roofing, how the cost of these materials compare, and tips to maintain a flat roof. Let’s get started!

Top 5 Best Flat Roofing Materials

As discussed above, there are lower costs associated with the construction of flat roofs. Keep reading as we break down the best materials for flat roofs!

1. PVC Roofing

PVC Roofing ProsPVC Roofing Cons
One of the most popular flat roofing materialsThere are many sustainability concerns
Low maintenanceIt is one of the more expensive options
Very durable and has a multi-decade lifespan
Water-resistant and not prone to leaking

Polyvinyl chloride, or PVC, is widely considered one of the absolute best materials for flat roofs. PVC roofing material is made from processed petroleum and can be bought in large, single-ply rolls. In terms of single-ply roofing options, PVC is perhaps the most popular choice of material.

There are many advantages to PVC roofing. PVC roofs are highly durable and don’t require much maintenance. Flat roofs constructed with PVC are known to last as long as thirty years. This roofing material is watertight, fire-resistant has great wind resistance, and is resistant to pollutants.

However, many designers are outspoken about the threat PVC poses to the environment regarding sustainable materials. This is due to the toxic chemicals that are released when this roofing material is manufactured. Luckily, PVC is not your only option when it comes down to flat roofing materials.

2. TPO Roofing

TPO Roofing ProsTPO Roofing Cons
Fairly popular and gaining widespread usageInsufficient data regarding long-term performance
Extremely lightweightYou may have trouble sourcing this material
Very durable
Non-pollutant and won’t contaminate rainwater

Thermoplastic polyolefin, or TPO roofing, is another great single-ply roofing material option for you to consider. TPO as a roofing material is gaining much popularity in the roofing industry. There are plenty of good reasons for this!

For one, TPO is a highly durable material that can protect your roof from threats like UV and chemical exposure. Furthermore, this material will not pollute the rainwater that runs off your rooftop. This material is also a lightweight roofing option that doesn’t require much maintenance.

Given that TPO’s popularity is still on the rise, there hasn’t been sufficient time to observe how different TPO offerings perform in the long term. This means that TPO could be a riskier material choice, especially when finding a reputable vendor due to its novelty.

3. BUR Roofing

BUR Roofing ProsBUR Roofing Cons
Great expected lifespanHard and long installation process
Extremely durableVery heavy material that needs adequate support
Perfect for roofs where people will often hang outRepairs can be difficult
Non-flammable

Built-up roofs, or BUR roofing, are constructed out of multiple layers of various materials. These materials–including ply sheet, cover board, and insulation–are bonded together on your rooftop with asphalt.

This layered approach to flat roofing is great for longevity, with each layer of material extending the built-up roof lifespan by an approximated five years. The layer of stones and gravel used to complete a built-up roof is great protection against debris that could harm other roofs.

This is a great option for those who plan to utilize the exterior rooftop space and expect more foot traffic on top of their flat roof. The chances of your built-up roof catching on fire are also unlikely due to the layers of materials used.

Unlike other material options, this layered flat roof can be pretty heavy and takes longer to install. Care will need to be taken to ensure the underlying structure can adequately support a built-up roof. Due to the layered nature, repairing a leak can also be more challenging than with single-ply flat roofing options.

4. EPDM Roofing

EPDM Roofing ProsEPDM Roofing Cons
Extremely customizable and versatileIt can be difficult to install
Very durable and has an exceptionally long lifespanProne to leaking if improperly installed
Easy to repair
Affordable
Works well in nearly any climate

Ethylene propylene diene terpolymer, also abbreviated as EPDM, is a durable rubber roofing material that you can use to construct a flat roof. There are a few different ways this roofing can be installed, making it a more versatile roofing option. There are also plenty of advantages!

EPDM is perhaps one of the most durable options for the various materials to construct flat roofs. These roofs are known to last up to fifty years! This material is also single-ply and is easier to install than some other flat roofing materials.

The longevity of this rooftop is due primarily to the natural elasticity of EPDM, which allows your rooftop to adapt to the climate. Furthermore, this material is not only affordable and straightforward to repair but is naturally fire-resistant, too.

When a flat roof constructed out of EPDM is not installed correctly, you could be more prone to developing leaks. Therefore, hiring a skilled contractor with experience working with EPDM is essential if you decide to use this material.

5. MB Roofing

MB Roofing ProsMB Roofing Cons
Similar to BUR roofing, but easier to repairConsidered somewhat fragile
Very easy to installSignificantly shorter lifespan than similar materials
Extremely water-resistant and not prone to leaking
Energy-efficient and good thermal performance

Modified Bitumen roofing, also referred to as MB roofing, is an asphalt-based option that is remarkably similar to built-up roofing, which we discussed earlier. Unlike layered BUR roofs, modified bitumen is a single-ply roofing material that is easy to install on flat roofs.

Not only is this type of roofing material easy to install due to the self-adhesive rolls that are readily available, but these are great waterproof options. MB roofing is a great material due to its water resistance and tight seal that help protect you from unwanted leaks.

This material is known to be fragile. This is not the best flat roofing option for those who want to utilize their exterior rooftop space. Furthermore, when compared to flat roofs constructed of other materials, MB roofing has a shorter lifespan.

A modified bitumen roof will likely need to be replaced somewhere between the ten- and twenty-year mark. For those looking for a flat roof that is durable with a long lifespan, they’ll be better suited to one of the options discussed above, such as PVC or TPO.

Flat Roofing Materials Cost Comparison

Now that we’ve examined the advantages and disadvantages of different materials that you can use to construct your flat roof, you’ll have a better understanding of the options available to you. Now it’s time to consider the cost of these options.

We’ve broken down the pricing of these materials by the average cost per square foot needed. This will allow you to better estimate how much your chosen roofing material will cost you. We’ve ordered them from the cheapest roof materials to the most expensive. Let’s take a look!

Flat Roofing MaterialsAverage Cost Per Square Foot
EPDM (Ethylene Propylene Diene Terpolymer)$1-$4
TPO (Thermoplastic Polyolefin)$2-$5
BUR (Built-Up Roof)$3-$6
MB (Modified Bitumen)$4-$6
PVC (polyvinyl chloride)$6-$12

What Makes Flat Roofs So Desirable?

There are many great benefits of choosing this type of roofing when it comes down to flat roofs. When you decide to get a flat roof, you’ll be able to begin reaping the benefits of a flat roof before it’s even constructed. Let us explain why–along with four other advantages of this type of roofing.

Flat Roofs are Cheaper to Construct

The slope of your home’s roof–and how shallow or steep it is–plays an important role in the amount of material needed for construction. Due to this, there are lower construction fees for flat roofs. You won’t even need to paint your rooftop.

Not only are flat roofs cheaper to construct, but they’re cheap to repair when needed. This means that your flat roof will save you money from the moment construction starts and well into the future. A flat roof is a smart, cost-efficient financial investment!

Flat Roofs are the Modern Choice

Not only are flat roofs inexpensive to construct, but they’re the more modern roofing option. Many people associate steep, pitched roofs with antiquated architectural styles. On the contrary, the flat roof is a popular trend for modern, contemporary buildings.

If you’re striving towards a more modern aesthetic with your home, then the type of roof you choose plays a vital role in achieving the desired look. For this reason, the kind of roof you choose is an important aesthetic consideration.

Flat Roofs Improve Energy Efficiency

Homes with steep, pitched rooftops have a lot of room for air to fill the house. This means that heating and cooling homes with these antiquated roofs are often costly. On the other hand, a flat roof means your home does not have unnecessary overhead space.

Depending on the materials used to construct your roof–which we’re about to break down–you can reduce your flat roof’s surface temperature by up to forty percent. In turn, this lowered rooftop surface temperature means that heat transfer is limited. If you’re striving towards efficient energy in your home, a flat roof is a step in the right direction.

Flat Roofs Maximize Interior Space

With pitched roofs, utilizing the interior rooftop space can be awkward with all those slanted walls. On the other hand, flat roofs allow homeowners to capitalize on all interior space without the awkwardness!

From a top-floor living area to an attic with maximized storage potential, flat roofs will allow you to utilize the space below effectively. Not only that, but your rooftop can be used from the outside, too.

Flat Roofs are Highly Versatile

Unlike steeply pitched roofs, it is possible to construct a flat roof in a way where you can utilize the space on the roof. For starters, this means that having a flat roof makes the installation of an air conditioning unit that much easier. Accessing it on your rooftop will also be an easy and safe process!

However, your flat roof has far more potential than just getting an air condoning unit installed. Whether you want to craft a lush rooftop garden or a rooftop patio to kick back with loved ones, there are countless ways to utilize your rooftop space with a flat roof.

Tips for Maintaining a Flat Roof

Earlier in this article, we looked at how the material used for construction can influence the lifespan of your flat roof.  However, another important aspect that will determine the lifespan of your flat roof is how you look after it. Keep reading as we break down five essential maintenance tips for your flat roof!

Keep Your Flat Roof Clean

One of the biggest complaints people have about flat roofs is their tendency to collect debris. With pitched roofs, owners have gravity on their side, with debris simply sliding off the rooftop. With a flat roof, you’ll need to ensure that you keep your flat roof clean.

This will help prevent the collected debris from disrupting the flow of water on your rooftop, which in turn could cause a leak. By keeping your flat roof clean, you’ll be able to steer clear of these issues!

Make Sure Your Drainage System Functions Properly

As mentioned above, debris that collects on top of your flat roof can cause drainage problems. When this accumulated debris is not cleared away in time, it can wind up within your drainage system, causing a clog.

This can lead to a wide variety of other issues, such as excess rainwater pooling on your rooftop. That is why it’s crucial to routinely check that your drainage system is functioning as it should. It would be wise also to inspect your rooftop when checking your drainage system.

Regularly Inspect Your Rooftop

Often flat roofs require more effort to maintain than pitched roofs. However, with regular inspections of your rooftop, you’ll be able to make sure that your roof stays in perfect condition. Luckily, due to the nature of these rooftops, many issues can be spotted when you’re on your roof.

Maintenance checks should be done regularly, but especially following a storm. This is when your roof collects debris from the wind, and rain could pool when debris blocks the drain. Unlike pitched roofs, you’ll need to get onto your roof to survey it. Luckily, getting up there is safer due to the flatness!

Don’t Overload Your Flat Roof

This is an important aspect to keep in mind if you want to maximize the lifespan of your flat roof. It’s an even more important factor to keep in mind if you plan on utilizing your exterior rooftop space. Your flat rooftop will be able to support a certain amount of weight.

It’s important to find out exactly how much weight your flat roof can sustain so that you can keep this in mind. If you’re unsure, the designers and builders of your flat roof will be able to provide you with this information. This helps prevent the threat of your flat roof collapsing! 

Be Wary of the Surrounding Environment

As mentioned earlier, flat roofs tend to collect debris. While you should always ensure your flat rooftop is clean, there’s a way to ensure that the cleanup isn’t too time-consuming. By trimming back trees near your rooftop, especially those that hang over your roof, you can minimize the debris your roof collects.

With the above in mind, you should inspect your garden for trees that could clutter your rooftop and trim them as needed.  Not only will this make cleaning your rooftop that much easier, but it’ll prevent rogue branches from damaging your flat roof and will help keep your drainage system working properly! 

Conclusion

Flat roofs are becoming increasingly popular. Not only are flat roofs considered the modern standard for rooftops, but they boast plenty of other advantages. In this article, we looked at the benefits of these contemporary rooftops, the best materials for constructing them, and tips to maximize the lifespan of your flat roof.

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Hubert Miles

I've been conducting professional home inspections since 2002. I'm a licensed Home Inspector, Certified Professional Inspector (CPI), Certified Master Inspector (CMI), and FHA 203k Consultant. I started HomeInspectionInsider.com to help people better understand the home inspection process and answer questions about homeownership and home maintenance.
DISCLAIMER: The content published on HomeInspectionInsider.com is not professional advice. You should consult with a licensed professional and check local permit requirements before starting any project.
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