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Commercial Flat Roof Replacement

Reasons for roof replacement include roof failure, leakage, aged and worn out materials or a recently purchased property that requires updates. Installing an A/C unit on the roof, a plumbing stack, an exhaust vent, a skylight, or other such additions may also necessitate roof replacement. Should your roof require renewal, depending on its state and your aims, it may be advisable to replace the entire rooftop, or to explore options for partial replacement.

There exists three systems for commercial flat roof replacement. The first can be combined and patched with the second, while the third can only be combined with itself. Your objectives and your budget will determine the best option to meet your needs.

Commercial Flat Roof Replacement
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Tar and Gravel System

This is an older, tried and true system which is less common today, but most effective in protecting a flat roof from improper drainage, or ponding. A tar and gravel roof doesn’t have a manufacturer, but is made with four layers of boiled tar and felt, with a “flood coat” of tar on the top and gravel spread evenly over that. A tar and gravel roof can be submerged under water for long periods of time and still last, as there are no seams or cracks where water may seep through.

If you choose to do patchwork on a tar and gravel system, there is a good chance we will opt for a 2-ply system. The 2-ply rolls will effectively adhere to the roof’s protection board as the surrounding tar is torched to help melt the patch into place.

Modified Bitumen 2-Ply System

This system consists of three-foot rolls with a three-inch overlap at the seams and a cap sheet that may be exposed to the sun. This system is more cost-effective than the first, but leaves the building vulnerable to eventual potential leakage issues, as it cannot remain submerged underwater over a long duration due to the creases. If your flat roof has a gentle slope which aids with drainage, and you are diligent about roof maintenance, this may be the option for you. This system may only be repaired with the same system.

1-Ply System

This system consists of only the cap. While it’s the most cost-effective option, it has overlap seams, meaning it does not fare well over long periods of submersion under water.

Contact us for pricing, which varies based on your area as well as your roof’s requirements for reparations and the system you decide to choose.

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