What is a Rubber Roof? Your Ultimate Guide to Rubber Roofing

rubber roof types

Rubber roofing has multiple applications—the most common being low-sloped and flat roofs.

Traditional shingles work well to repel moisture on steep roofs, with the help of gravity. But shingles don’t create the type of watertight seal needed to protect a low-pitched or flat roof from water.

On low-sloped or flat roofs, roofers often use specially-manufactured roofing materials made of rubber or PVC plastic. This type of roofing is known as rubber roofing. 



 

Benefits of Rubber Roofing

rubber roofing energy savings

Single-ply rubber roofing is the ideal material for flat and low-sloped roofs because of its durability and water resistance.

Each type of rubber roofing material—whether it contains synthetic rubber polymers or plastic polymers—was specifically designed to protect low-sloped roofs from water damage.

Rubber roofing has many benefits, including the following:

• Long lifespan of 20-25 years on average and up to 50 years in some instances.
• Easy cleaning and maintenance.
• Energy savings.
• Improved curb appeal.
• Relatively short installation time.

Rubber Roofing Applications

Rubber roofing has numerous applications and uses. Below, we’ll go over the three most typical applications for rubber roofs.

Flat and Low-Sloped Roofs

The intended application for rubber roofing is on flat and low-sloped roofs, where shingled roofing isn’t the best option.

Shingled roofing is the perfect choice for steep-pitched roofs, but it isn’t ideal for low-sloped roofs.

This is because shingled roofing uses a stacked formation (one on top of the other with overlapping ends) to repel water as it travels downwards off the roof.

On low-sloped or flat roofs, water can drift in different directions and seep in between the shingles, causing leaks.

For roofs where shingles aren't the ideal choice, rubber roofing is often the most practical solution. Rubberized roofing materials repel moisture and protect the structure underneath from pooling water.

 

On Top of Your Shingled Roof

Rubber roofing isn’t only relegated to the field of flat roofs. It can also be used on pitched roofs, as a way to extend the lifespan of the existing roof structure and add value to the home.

On sloped roofs, rubber roofing is typically applied over the top of the existing shingles. A roofer can apply a layer of insulation onto the shingles, followed by the rubber membrane.

This option can save you money in the long run since rubber roofs tend to last longer than other types of roof replacement.

As an added benefit, installing a rubber roof on top of your shingled roof can dramatically lower your energy costs by insulating and deflecting heat away from the home.

 

Fixing a Metal Roof

Metal roofing is another popular low-sloped roofing option. Metal roofing can last many years, but when it becomes rusted, leaky or damaged, it can be difficult and costly to replace.

If you have a damaged metal roof, a rubber roof may be a better solution. Rather than going through the process of tearing off the existing metal roof, you can install a rubber roof over the top.

Similarly to installing a rubber roof over the top of a shingled roof, topping a metal roof with a rubber roof can improve curb appeal and reduce energy costs significantly.

 

Types of Rubber Roofing

types of rubber roofing

 

Nearly all modern flat roofs are topped with one type of rubber roofing membrane or another.

But as mentioned above, not all rubber roofs are actually made of rubber, and not all are created equally. Each type of rubber roof material and system has its own pros and cons.

Below are the rubber roof options for installing or replacing a roof.

1. EPDM

Ethylene propylene diene terpolymer, or EPDM, is one of the most popular materials for flat roofs.

 

Pros of EPDM Roofing:

 

  • Long lifespan. EPDM has one of the longest lifespans of all rubber roofing materials.

 

  • Original rubber roof. EPDM is the original rubber roof product, which means it’s stood the test of time.

 

  • Lower cost. EPDM is one of the lower-cost options when it comes to rubber roofs.

 

Cons of EPDM Roofing:

 

  • Absorbs heat. EPDM is naturally black, so it offers less heat protection than rubber roof materials that are lighter in color. EPDM can be ordered in grey or white for an additional cost.

 

  • Potential weak seams. EPDM seams are sealed with adhesive or tape, which leaves them more prone to leaking than hot air-welded seams.

 

2. TPO

Thermoplastic polyolefin, or TPO, is a single-ply roofing material that is similar to EPDM but different in several key ways. First, TPO is a relatively new product in the roofing industry, which means it’s not as time-tested as EPDM and PVC roofing.

However, TPO was created as a more economical and energy-efficient alternative to these other rubber roofing materials, making it a popular choice.

 

Pros of TPO Roofing:

 

  • Durable and flexible. TPO is highly flexible, which means it can better withstand impacts and other types of potential damage.

 

  • Environmentally friendly. TPO doesn’t contain some of the chemicals used to produce other roofing materials, including chlorine. TPO is UV resistant (and can be ENERGY STAR rated), which means you can use less energy to cool your home in the summer. TPO is 100% recyclable.

 

  • Hot air technology. TPO is hot air-welded, making the seams strong, flexible, and highly water-resistant. The seams of a TPO roof are up to four times stronger than EPDM seams, which must be sealed using adhesives.

 

  • Color range. TPO is available in white, but it can also be manufactured in grey or black for aesthetic purposes.

 

Cons of TPO Roofing:

 

  • New technology. TPO was introduced to the roofing industry in the 1990s, making it a relatively new rubber roofing material as compared to the others.

 

  • Inconsistent formulas. TPO manufacturers are still working out the best formulations for their businesses and for their customers. Some manufacturers produce TPO products that are less expensive but more prone to failure. When you install a TPO roof, it’s essential to choose a roofer who uses a high-quality TPO product.

 

3. PVC

Polyvinyl chloride, or PVC, is similar to TPO in that it’s made of thermoplastic materials. It offers similar benefits in terms of flexibility and water-resistance, with similarly hot air-weldable seams.

However, PVC contains plasticizers and chlorine salts, giving it different benefits and drawbacks from TPO.

 

Pros of PVC Roofing:

 

  • Even more flexible. The plasticizers and other chemical components of PVC rubber roofing make it even more flexible than TPO. This makes it resilient and resistant to building-settling.

 

  • Time-tested product. Roofers have been using PVC for over 50 years. As a long-time industry favorite, it’s easier to find a roofing contractor who specializes in PVC roofing than in a newer product like TPO.

 

  • Energy efficient. Like TPO, PVC is energy efficient and can help reduce your cooling bills during the warm summer months.

Cons of PVC Roofing:

 

  • Chemical breakdown. The plasticizers and chemical components of PVC rubber roofing usually cause it to break down faster than TPO or EPDM.

 

  • Contains chlorine. PVC rubber roofing contains the chemical chlorine, making it a less environmentally-friendly option than TPO.

 

How Long Do Rubber Roofs Last?

how long does a rubber roof last

 

Rubber roofing, when installed professionally, can last 25 years or more. TPO and EPDM roof systems have similar lifespans of 20 to 25 years.

High-quality TPO roofing that is reinforced with fiberglass can last even longer.
Modified bitumen roofs last an average of 10 to 12 years, and built-up roofs (BUR) last between 15 and 20 years.

Compare these lifespans to the life expectancies of other common roofing materials.

 

Cost to Install a Rubber Roof

Many homeowners make the mistake of assuming that flat roof installation and work is less expensive than pitched roof work. After all, flat roofs are much less complicated to access, and it’s a lot easier to move around on a flat surface than on a sloped one.

However, many roofers will attest to the fact that working on flat roofs is more physically taxing than working on steep ones. Flat roof work may not call for a harness and brace system, but it does involve more stooping, bending, and lifting than pitched roof work.

Additionally, flat roofs require more elaborate installation processes that involve the handling of adhesives and the use of sophisticated application techniques.

For these reasons, installation and labor costs for a flat roof can be as high as—or higher than—those of a pitched roof.

Rubber roofing materials are typically more expensive than traditional composite shingles, as well. However, a rubber roof will last longer and offer more benefits than asphalt shingles or asphalt roll roofing.

 

Maintaining a Rubber Roof

maintaining rubber roofing

 

If you have a rubber roof, or you’re considering installing one, it’s important to know how to maintain rubber roofing correctly.

 

1. Regular inspection.

Inspect your sloped rubber roof regularly from the ground, if you can. If you can’t see the top of your low-sloped or flat roof, use a ladder to climb up onto the roof safely and cautiously. (If you don’t feel safe doing so, always call a professional roofer instead.)

Inspect the roof for debris, as well as any areas that look damaged or appear to be crumbling or cracking.

Check the seams for lifting—even what may seem like minor pealing—as well as the areas around flashing and roof fixtures.

 

2. Gentle cleaning.

Several times per year, you should clean your flat rubber roof to remove built-up debris. Use a soft broom to gently brush leaves and other small debris off of the roof. Use a mild detergent and wet mop to lightly scrub stubborn spots.

 

3. Gutter care.

An essential part of maintaining any roof system is making sure your gutter system is working correctly. Each year, gently clean debris out of the gutters and check for damage. If the gutter is cracked, sagging or leaking, call a professional to make repairs.

 

4. Professional maintenance.

If you notice any level of damage to your rubber roof, or if your roof has been impacted by a large tree limb or other large debris, call a professional roofer for a thorough inspection.

 

Alternatives to Rubber Roofs

rubber roofing alternatives

If you need to replace your low-sloped or flat roof, you have a few different flat roof options. The following are the most popular alternatives to rubber roofing.

 

Asphalt Roll Roof Systems

The most common rubber roof alternative for flat and low-sloped roofs is asphalt-roll roofing. Asphalt roll roofing is applied in sheets in a fairly easy installation process.

For this reason, asphalt roll roofing is popular for sheds and small buildings, as well as for do-it-yourself projects.

However, asphalt roll is only a temporary roofing solution, as it has a very short lifespan.

 

Modified Bitumen and Built-Up Roofing

Modified bitumen is also known as roofing tar, and it’s a popular choice for flat and low-sloped roofs.

Modified bitumen systems can be applied as a self-adhering compound or using torch-down application. It is also used in built-up roofing (BUR) systems.

Modified bitumen and BUR roofs tend to have a shorter lifespan than rubber roofs, and they don’t offer the same energy-saving benefits.

 

Composite Shingles

Shingles aren’t the ideal roofing material for flat roofs, as discussed above. But it is still possible to use conventional composition shingles on a low-sloped roof.

To do so, the roofing materials need to be installed differently than you would do with a sloped roof.

Although shingled roofs can be less expensive than rubber roofs, this intricate application process will raise the price, and the roof won’t last as long as a rubber roof would.

 

Sealing a Metal Roof

If you’re considering sealing a leaking metal roof with a rubber roof, an alternative option is to top your existing metal roof with a one.

This would involve covering the existing roof with a layer of insulation, followed by the new metal roofing. Depending on your roof, however, installing a rubber roof may be the more affordable option.

Another option if your metal roof is leaking is to reseal the roof with fiberglass webbing.

 

Hire the Right Rubber Roofer

As with any other type of roof, hiring the right rubber roofing contractor is the most important step.

When installed correctly by a skilled roofer, a rubber roof can last 20 to 25 years.

But an incorrectly installed rubber roof will need to be replaced within just a few years. More importantly, a roof that’s installed incorrectly can cause damage to the structure underneath.

If you’re in the D.C. area and in need of a rubber roof contractor, contact us at Capitol Improvements for a quote.

Our Comprehensive Guide to Flat Roofs: Materials, Application, Design and More

flat roof guide

Flat roof systems require special attention that pitched roofs do not. If you own a home with a flat roof, it’s important to understand flat roof materials and construction, maintenance requirements, and everything else involved in taking care of your roof.


  1. Flat Roof Materials & Construction (top)
  2. Maintenance
  3. Flat Roof Myths and Facts
  4. Flat Roof Financing and Warranty with Capitol Improvements

Flat Roof Materials & Construction

flat roof materials

Homeowners can choose from several different types of flat roof materials, each of which has its own application and construction process, as well as its own pros and cons. The three main types of flat roofs are:

  • Modified Bitumen Systems or MBS, including:
    • Torch-down systems
    • Self-adhering systems
  • Thermoplastic polyolefin or TPO
  • Ethylene propylene diene monomer or EPDM

1. Modified Bitumen Systems (MBS)

Modified Bitumen Systems (MBS)

Modified bitumen roofs are one of the most popular types of flat roof systems in commercial/industrial applications, and they're used residentially, as well. Modified bitumen systems (MBS) have become a popular alternative to built-up roofs (BUR) because MBS is lighter and more durable.

Modified bitumen is a type of bitumen (tar or asphalt) combined with a modifying compound, thus improving its performance. The two most common compounds used to modify roofing bitumen are: atactic polypropylene (APP) and SBS (styrene-butadiene-styrene).

The two common methods for applying modified bitumen flat roof systems are:

  • Torch-Down Application (Torch Application)

Torch-down roof application is the process of adhering levels of modified bitumen (APP type) through the application of high heat.

  • Self-Adhering or Mop Application

SBS modified bitumen can be applied “cold” or without the use of high heat because of the addition of the styrene-butadiene-styrene compound. This process consists of applying self-adhering sheets or mopping the bitumen onto the roof platform.

Lifespan

10-12 years when properly applied in appropriate settings.

Benefits

  • It comes in a variety of different types/applications to suit each home and homeowner.
  • It is less complicated and requires less labor time to install than built-up flat roofs.
  • Less complicated installation also means there is a smaller possibility of errors during installation.
  • It is relatively low-cost.
  • Modified bitumen is more flexible than built-up roofs, making it more elastic and durable against freezing temperatures.
  • It can be recycled at the end of its lifespan.

Drawbacks

  • Torch application requires an open flame to apply, which requires special safety considerations.
  • Extra attention must be paid to overlapping joints and pieces to avoid leaks.

 

2. Thermoplastic Polyolefin (TPO)

TPO roofing is a type of synthetic “rubber roof”, consisting of a single-ply layer or membrane of thermoplastic polyolefin material. TPO is a popular material used in residential flat roofing applications because it is light-weight, highly reflective, and weather-resistant.

It comes in a standard white color, which helps prevent the absorption of heat. TPO roofing is also a popular choice for homes and buildings which have low-pitched (as opposed to flat) roofs because it can improve curb appeal with a unique appearance and is highly energy-efficient.

Lifespan

The average lifespan of TPO roofing is 20 years with proper installation and maintenance.

Benefits

  • It has superior water resistance and leak protection.
  • It is resistant to heat and UV rays.
  • It is relatively cost-effective.
  • TPO is relatively low-maintenance and easy to repair.
  • TPO roofing is 100% recyclable.
  • It offers reduced energy costs, especially in cooling costs.
  • Relatively resistant to tearing and scratching.
  • TPO is very lightweight, so roof decks and joints do not need reinforcement.

Drawbacks

  • TPO will age faster in regions with hotter temperatures.
  • It’s important to make sure your TPO roofing product is high-quality and installed by a qualified professional, since many poor-quality TPO roofing products exist in the market.

 

3. Ethylene Propylene Diene Monomer (EPDM)

Ethylene Propylene Diene Monomer (EPDM)

 

EPDM, or ethylene propylene diene monomer, is another type of synthetic rubber roofing material. Like TPO, EPDM is commonly used as a single-ply membrane. However, EPDM differs from TPO in several ways.

EPDM is an older roofing technology than TPO, so it is considered more time-tested and trusted. However, EPDM does not offer the same heat-resistance and energy-saving technology as TPO roofing.

Over the years, EPDM roofing has evolved and is now available in peel-and-stick membranes, making for quick application.

Lifespan

The average lifespan of an EPDM rubber roof is 25 years when properly applied in appropriate settings

Benefits

  • EPDM rubber roofing is waterproof (leaks are rare) and highly durable -- EPDM roofing doesn’t scratch easily.
  • Repairs are relatively simple.
  • EPDM is lightweight, so the roof deck typically doesn’t require reinforcement.
  • EPDM roofing has a longer lifespan on average than either TPO or MBS.

Drawbacks

  • Exterior pipes, HVAC systems, chimneys, etc. can cause leaks unless properly flashed.
  • It can be damaged by branches and storm damage.
  • It is more prone to damage from foot traffic during and after installation.
  • EPDM does not reflect heat like TPO.

 

Maintenance

flat roof maintenance

One of the biggest reasons homeowners avoid flat roofs is because they require more maintenance than pitched roofs. However, if you know how to properly maintain a flat roof, you can mitigate this issue and enjoy the benefits of your flat roof without worry.

The following are the most important considerations when it comes to maintaining your flat roof.

1. Traffic Damage

This is number one our list because, to perform any type of maintenance or check on your flat roof, you’ll need to climb up and step foot on the roof. Your weight shouldn’t be enough to cause damage if the roof is properly installed. However, scuffing, scratching, or digging into roofing materials with sharp tools can damage a flat roof’s moisture-protectant layers.

2. Drains and Scuppers

Keeping the roof’s drains and scuppers clear is the second-most important step in maintaining your flat roof. Clogged drains make it impossible for water to drain off of the roof, forcing water to pool up on the roof instead.

3. Leaves and Debris

Gently sweeping the roof to prevent leaves and debris from building up can go a long way in maintaining your flat roof. Especially in the autumn months when leaves begin to fall, you’ll want to make sure you remove them from your roof before they turn to mulch.

4. Low Branches

Check the trees surrounding your house for low-hanging branches that touch--or come close to touching--your roof. These can easily begin to scrape and damage the roof before you have time to notice.

5. Caulking and Flashing

When you check your roof for damage, always check the caulking and flashing. These two parts are easy to replace, but if not maintained, can damage your entire roof system.

6. Professional Help

While some minor damage can be fixed DIY with patch kits from your local home center, larger or deeper cracks and splits require professional tools, experience, and equipment. If you’re not confident that you can seal any damage in a way that is completely watertight, call in a professional contractor for help.

 

Flat Roof Myths and Facts
flat roof myths and facts

 

Flat roofs improve energy savings.

Fact:

TPO flat roofs work to repel UV rays and prevent heat absorption, which means you can spend less money on cooling your home during the hot summer months.

 

Maintenance and repairs are easier on flat roofs.

Myth:

While it may be easier to climb up and walk around on a flat roof, they also require special equipment and knowledge to maintain and repair. Flat roofs also require much more regular maintenance than pitched roofs.

 

Flat roofs add usable space to your home.

Fact:

If you’ve ever been in the upstairs or attic space of a home with a steep-pitched roof, you know just how much space those roofs can take up. Valuable square feet can be saved by choosing a flat roof, which leaves all of the space underneath fully usable.

A flat roof also adds extra usable space to the exterior of a home, whether that means attaching the HVAC unit to the roof or installing a garden or rain buffering system atop your home.

 

Flat roofs are less expensive to install or replace.

Myth:

Because they require special training and expertise to install correctly, flat roofs are typically more expensive to install or replace than pitched roofs.

 

Flat roofs are perfectly flat, so they can’t shed water.

Myth:

Building codes usually require even “flat” roofs to have a minimum pitch of at least 1%, or ⅛” per 1’. Some building codes even require a slope of at least 2%. This minimum slope is enough to accommodate water runoff and to help prevent water damage. Flat roofs also utilize waterproof membranes to deter moisture.

 

Flat roofs don’t last as long as pitched roofs.

Fact:

Because they are more prone to moisture, debris, and heat damage over time, flat roofs must be replaced more frequently than pitched roofs. However, modern materials like TPO and EPDM have extended the lifespan a great deal in recent decades, and flat roof technology continues to improve.

Flat roofs are a bad idea in hot regions.

Myth:

While they may not last as long in areas of extreme heat, flat roofs made of materials like TPO can work well in even the hottest regions. We recommend TPO because it is white in color and works to reflect heat away from the home. Issues like cracking and blistering usually occur from improper application of roofing materials like modified bitumen and synthetic rubber.

You can replace a flat roof yourself.

Myth:

DIY sites may claim that installing new flat roof materials like TPO and EPDM is simple enough to do yourself, but doing so can result in leaks, damage, and a roof replacement that lasts no more than a few years. Correctly replacing a flat roof requires the proper equipment, as well as professional training and experience.

 

Flat Roof Financing and Warranty with Capitol Improvements
Flat Roof Financing and Warranty with Capitol Improvements

With Capitol Improvements, you can trust your new flat roof to last for years or decades to come.

 

Capitol Improvements Flat Roof Warranty

Material Warranty Period
Modified bitumen 12 years
TPO 20 years
EPDM 25 years

 

Capitol Improvements also offers easy financing for projects like flat roof replacement, with options for great and not-so-great credit.

If you live the DC area, contact us at Capitol Improvements to learn about how you can finance or get started on your flat roof project.