commercial roof vacuumA ballasted roofing system is popular for commercial roofs because of its durability and affordability. Ballasted roofs are a roofing system in which the roof membrane is not anchored or adhered to the decking material, and is instead kept secure by stone placed on top. The gravel also serves to protect the underlying roof layer from the elements, including uv rays, hail, and other precipitation.

When it comes time to repair these roofs, some unique equipment comes into play – including a special vacuum that removes the rocks from the roof.

Quality Roofing’s Kyle Tisdell recently demonstrated this specialized process at Abbotsford Schools, whose ballasted roof is in the process of being repaired and upgraded.

Tisdell learned how to operate the vacuum from longtime Quality Roofing team member Dave Schug, and together the two have completed this important repair step on buildings including the Wisconsin State Capitol, Aspirus Hospital in Wausau, and others.

“We’ll take the rock off, peel the rubber off, add a layer of insulation, put new rubber down and bring in new rock to put back down,” he said of this project. “The new rock is a washed river rock that is really round. Some people are going with a more light-colored rock because it reflects the sun better and can help regulate temperature.”

The vacuum sucks up the rocks, which are then moved through a large hose and deposited into a hopper. Once the hopper is full, the rocks are released into a dump truck that has been specially retrofitted to accommodate the specialized machinery. The mechanism is powered by a special diesel engine that can generate a significant amount of power.

Rock on the Abbotsford roof will travel 280 feet to the hopper. At about 12,000 square feet, Tisdell and Schug expect vacuuming to take about 20-22 hours depending on the weather.

“It’s definitely faster than using a shovel!” he said.

The furthest Tisdell has suctioned rock using the vacuum is 875 feet during a project at Aspirus Hospital in Wausau.

During any project, safety is paramount.

“Safety is really important to Quality Roofing. We tend to not like falling off roofs!” said Tisdell. “I follow the same safety procedures when vacuuming as I would when putting a new roof down.”

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