For the Commonwealth Assisted Living at Abingdon, Virginia, just north of the Tennessee border, things seemed hopeless. Residents and employees alike had been dealing with a leaky roof for years, and there was no solution in sight.
The wood joist and 26-gauge R-panel metal roof was 34,000 square feet (3158.7 m²). An engineer hired by the general contractor (GC) had investigated several waterproofing options, including metal on metal or flute-filled with a singly ply, and they had included structural and load bearing tests for the various solutions. It appeared that the only viable option was a complete roof replacement, which wasn’t really possible with the nature of the facility since the building was constantly occupied. Nothing seemed to fit the bill — until Applied Coating Solutions (ACS) dropped by.
“It had kind of been put on the side for that general contractor, and then we went in and pitched that GC in general about silicone. And he said, ‘hey, we’ve got a project for you. They’ve been looking for us to help them with something for a while,'” explained ACS’s President Andrew Wilson.
Not only could the silicone solution meet the weight limit required by the engineer’s findings, but it would also fix those pesky leaks. After years of waiting for the right solution, the client was finally going to get its new roof! It time for the coatings crew to get cracking.
Prep Time
Despite the building only being one story tall, the roof had a 4:12 pitch and required that the crew wear proper fall protection throughout the project. They used butterfly clip harnesses and perimeter lines, along with other personal protective equipment (PPE) when necessary.
To start the prep, the three-person crew used 4,000 psi (27.6 MPa) pressure washers with Honda engines. Then, they replaced all failing pipe boots and fasteners. The fasteners that didn’t need to be replaced were tightened using Bosch impact drivers. And, all seams and fasteners were sealed using GE’s Enduris Liquid Flashing, applied with an 80-ounce (2.3 kg) Bulk Caulk gun from Albion Engineering and a Spot-Pro Extension Nozzle attachment. According to Wilson, that tool helps them cut down on prep time.
“Every one of those fastener heads gets encapsulated with that silicone as well as any pipes or horizontal lap seams. Typically, on a metal roof like this you’ll spend as much if not more time on detail work than actually spraying the roof if you do it right,” Wilson explained.
The crew used the same material over all horizontal laps. That was applied in a 2- to 4-inch (5.1–10.2 cm) bead, again using the caulk gun and also a brush to ensure coverage.
Wintry Conditions
With the prep completed, it was time for the crew to move on to the coating, GE’s Enduris 3500 silicone. Part of the draw for this solution in particular was that it didn’t require a primer. “A lot of manufacturers require two-coat application so that cut costs and made it more competitive as a solution,” Wilson explained. And, GE also offers the silicone in custom colors.
According to Wilson, GE is one of the only companies that can match any color to the coating. In this case, Commonwealth Assisted Living at Abingdon chose the high-solids 100-percent silicone to match the shingles, trim, and other accessories. The color was “cobble brown.”
The crew used a Graco Gas Hydraulic 933 Big Rig, an airless sprayer. They also narrowed their fan tip around the edges of the building to help control and avoid overcoating. Wind speed was a factor in that area, too, so other precautions were employed: “We did use a guard whenever we got near the rake edge to keep overspray from going over the rake,” Wilson said. “And we would ask them to move the cars when we were spraying on that slope facing the parking lot.” Once the cars were moved, the crew set up cones to keep the areas blocked off.
The crew applied the coatings at an average rate of 2 gallons (7.6 L) per 100 square feet (9.3 m²). Unfortunately, the silicone didn’t arrive on site until January when Virginia was already dealing with winter’s chilly temperatures. Although silicones can be applied below freezing, the cold weather did cause other conditions that the crew had to work around. That included frost on the metal roof, which then turned to ice — not great when coating. “Basically, the window we could install the silicone was shortened because we had to wait for the roof to be completely dry,” Wilson explained. They “had to wait for the ice to melt and then backpack blow that moisture off.” The crew’s window of work time shrunk to about five hours on those days (12–4 p.m.).
The crew prevailed. As Wilson said, “The crew’s great. They’re the best.”
Leak Free!
The project took eight days to complete over the course of about a month and a half. It was a winner for Commonwealth Assisted Living at Abingdon, who, according to Wilson, paid about half of what they would have for a complete roof replacement. “The client saved tens of thousands of dollars on this solution compared to removing and replacing the metal, which was the only other viable option based on the weight restrictions,” Wilson explained.
The project was also a winner for CoatingsPro’s 2018 Contractor Awards Program. ACS won third place in the Commercial Roofing category.
And, most importantly, the silicone solution is working! “They’ve been very happy with it,” Wilson said. “We haven’t had a single leak call on that project — knock on wood — since we finished it, so all good things.”
