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Modified Bitumen Roofing Systems

What Are Modified Bitumen Roofing Systems?

Is your commercial property long overdue for a new flat roof? Selecting a roofing system involves a lot more than comparing different roofs’ aesthetics and costs. Although your roof’s visual appeal and your bottom line are certainly important, you also must consider the system’s required maintenance, the installation and repair processes, and your needs as a property owner. To start, explore the pros and cons of modified bitumen roofing systems below.


What Are Modified Bitumen Roofing Systems?

Modified bitumen roofing is a specialized kind of membrane roofing. Unlike other membrane systems that only use synthetic rubbers and thermoplastics, modified bitumen incorporates layers that typically combine asphalt, solvents, and rubbers.

Manufacturers create modified bitumen roofing membranes to suit a variety of situational needs and industry specifications. For instance, some complete systems combine fire retardants with energy-efficient coatings and mineral granule surfaces that provide extra protection from the sun. Other formulations provide weather resistance and lasting durability in flat roofs and flashings.

The Pros and Cons of Modified Bitumen

Advances of Modified Bitumen

Membrane systems like modified bitumen are often preferred to flat asphalt and gravel roofing because they make it easier to create a continuous roofing surface. In other words, you’re less likely to run into problems creating roofing seals, which is certainly handy if you would prefer that your ceilings didn’t spout waterworks every time it rained.

In addition to minimizing the number of seams that roofs include, modified bitumen installations are known for being simpler to repair. Roofing experts can easily find leaks and create patches to repair them.

Your roof may seem like an unmoving building component, but it expands and contracts with changing temperatures. Exposure to sunlight also brings UV rays that break down materials like asphalt. Although no roofing can resist Mother Nature forever, manufacturers commonly choose combined membrane formulations that are made to withstand environmental wear and tear longer, so that you spend less money on maintenance.

Potential Drawbacks

Like all asphalt-bearing roofs, modified bitumen systems are black, which may increase the heat absorption of your home or office. Fortunately, it’s possible to overcome this problem by installing the correct insulation.

It is also important to choose the right thickness of roofing. Installing a one-ply system because it seems cheaper than a two- or three-ply alternative could cost you in the long run when it breaks down earlier than you expect.

Getting Started

Installation Basics

Traditionally, roofers install modified bitumen systems using heat sources like propane torches or hot mops. These processes allow the asphalt in the membrane to soften and slightly melt, so that the layers adhere to the roofing below. Some modern membranes also include self-adhesive surfaces or can be combined with adhesives for application at lower temperatures.

Of course, this is a simplification of the overall process. To install an effective built-up roof, roofers must start by inspecting and preparing the roofing substrate, whether it’s wood, concrete, metal, or insulation. During the installation, flashing surfaces must be primed to accept asphalt so that they don’t end up leaking, and base sheets may need to be nailed to the roof decking.

Modern built-up roofing incorporates complex blends of different layers and materials that work together to create durable, lasting protection for your property. Modified bitumen roofing systems have numerous advantages that make them highly popular among building owners. Thanks to these systems’ efficacy and relative ease of installation, your installer is also likely to appreciate the fact that you’ve chosen them.


Are you ready to purchase and install a modified bitumen roofing system? If you live in southern Missouri, contact Taylor-Made Roofing for help. With over 20 years of experience in residential and commercial roofing, Taylor-Made Roofing is a company that you can trust with all of your roofing needs. Our family-owned business offers quality services, a reassuring warranty, and free estimates. For more information, please give us a call at 417-326-8778 or contact us online. We look forward to hearing from you!

Fully licensed and insured, Taylor-Made Roofing is ready to take care of your roof.
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