My Rubber Roof Dilemma
Many seams were splitting or seemed ready to split.
I own a 6600 square foot commercial building, which houses Saturn and one other tenant. The roof is a 20-year-old black EPDM rubber which had puddles in five places. The roof had leaked for a few years during which time we paid a local roofer to search out and patch leaks. I procrastinated looking at the roof myself until a few months ago when water was running out of a light fixture in the upstairs hall. I went up there and realized that there were many weak spots that needed patching and that the roof had aged significantly since we bought the building 3 years ago. There are asbestos-containing materials under the rubber roof, making a tear-off out of the question. A new welded-PVC roof, installed over the 3300 square-foot existing roof, would cost around $30,000. Instead, I opted for white liquid EPDM from http://www.epdmcoatings.com/
The Prep Work
We spread the rubber roof coating with squeegies and smoothed it with rollers.
I bought an EPDM patch kit that included self-adhesive patches, cleaner, and EPDM primer. I hand-cleaned the worst areas and the obvious leaks and patched them, solving the leakage problem. However, many seams and low spots on the roof looked like they were evolving toward leaks. So, my friend Bob and I hauled a pressure washer up there and pressure washed the 3300-square-foot roof, scrubbing it with push brooms, for about 6 hours. We couldn’t believe how much dirt kept coming off in the water. We started with a medium spray but quickly realized we needed to go full bore if we were ever going to get finished. I was glad that I did a careful job of patching because there were no leaks from the pressure washing.
I cut the patch material into thin strips to cover seams. Here is the finished seam patch covered with the liquid rubber.
Spreading the Liquid EPDM
Lou at EPDM Coatings explained how to apply the coating and saved me from ordering too much. The material came in 17 5-gallon buckets, costing something like $280 each. Five of us showed up to spread it on the newly cleaned roof. Each bucket covers 210 square feet, and if you spread it right that number is accurate. We estimated the 210 square-foot area and dumped the bucket as evenly as we could on that area. Then we spread it with large squeegies and rolled it with paint rollers to smooth it out and remove the bubbles. The job took five of us about 5 hours.
In the next post I’ll tell you more about how the roof turned out.