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Why Your Flat Roof Should Be Fully Adhered (Instead of Ballasted)

Flat roofs are commonly protected with single-ply membrane systems that are great for years of leak-proof protection. These single-ply roof membranes for flat roofs are seamless and resistant to water, hail, snow, and wind. Sometimes, though, these commercial roof systems are installed using ballast to weigh them down instead of fully adhering the membrane to the roof substrate.

Let’s first look into what it means to have a ballasted roof and then we’ll explain why it’s not the best choice for commercial roof protection.

What Is A Ballasted Roof?

A ballasted roof is a protective membrane or rubber sheet, loosely applied to a flat roof, and held in place using tons of gravel.

This is an easy way to install a single-ply membrane roof system and is less expensive to install than traditional systems because it takes less time. It’s a tempting option for warehouse owners and others with buildings that are expansive and flat.

What are the Disadvantages of a Ballasted Roof?

In the long run, the cost savings of choosing a ballasted roof, single-ply installation may not be worth it.

Most worrisome is the weight that a ballasted roof adds to your building. You can expect to need about 17 pounds per square foot, although this will depend on the environment that your building endures year-round (high winds). This added weight can strain your building’s infrastructure. In wintertime, with additional snow loads, this could become quite a risk.

Maintenance on a ballasted roof, as opposed to a fully adhered single-ply roof system, is a nuisance. Leaks are much more difficult to detect through a layer of gravel. And to fully inspect a ballasted roof for leaks, we’d have to start shoveling it out of the way. This takes time; time is labor.

Also, some facility managers consider it acceptable to walk directly on a ballasted roof rather than follow designated walkways. This foot traffic is less than ideal as it can weigh down the gravel and push it into the membrane, consequently compromising the membrane’s ability to prevent leaks.

Why Choose a Fully Adhered Single-Ply Membrane?

roof membrane by keystone commercial roofing

Single-ply roofing membranes provide a seamless protective coating on a commercial building. Our rolled single-ply membrane system offers outstanding protection.

With a Class-A fire rating, single-ply membrane roofing systems drastically outperform traditional EPDM, making it the best choice for high-heat or flammable environments.

Keystone Commercial Roofing installs Conklin roof systems, which we believe are the best in the industry for superior protection and energy-efficiency. We fully adhere your new roofing system, overlapping layers to encourage water run-off. Each layer is welded and sealed for weatherproofing protection. We then use a urethane sealant to ensure a tight seal around edges and joints.

Choose the Right Commercial Roof Coating

For more than a decade, we’ve provided industrial roofing to commercial property owners in northwestern Pennsylvania, northeastern Ohio, and southwestern New York. Our roofing contractors offer superior solutions to revitalize your building’s metal roofing, EPDM, rubber, or PVC roof systems.

Learn more about our commercial roof coatings. We’re always happy to discuss which options work best for your needs and budget and will even inspect your current roof system for free.




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