Saving a Large Pool Deck From Mold

A look a the mold that was starting to spread on this pool deck.

Measuring the moisture in the concrete with a yellow meter.

Aquablok drain in the concrete.

When Steve Carver took a call from the lawyer representing the architect behind the recently completed $8.4 million Faucett Brothers Activity Center in suburban Tuscaloosa, Alabama, he didn’t expect good news.

He was right.

Carver runs Building Renovation Systems of Atlanta, specialists in building protection consulting, including concrete restoration work. The Faucett Brothers Activity Center is a 60,000-square-foot multi-purpose facility that opened on March 1, 2013. The county-owned center includes two indoor pools, a 6,500-square-foot pool deck, and, not so long ago, the fast-spreading stain of pool deck mold.

County officials “were panic-stricken,” according to Carver. “They were very upset. They called the architect. He didn’t know what was going on. The engineer and general contractor didn’t know what was going on. All they knew there was a problem. They just didn’t know why.”

Carver was asked to diagnose the problem. Why was mold suddenly blossoming across a nearly-new pool deck? Was it vapor drive from the underlying concrete slab? Or related to the adjacent pools? To narrow the possibilities, Carver ordered the pools drained.

“I wanted them bone dry. The only thing then would be ground moisture coming up from the concrete. I had more lawyers around me than I’ve ever seen in my life. I had to be very careful with my conclusions and remedy,” Carver observes.

Carver had Wagner RH test probes installed in a test section of the pool deck. The readings? Off the chart—99 percent. The underlying concrete slab was soaking wet when a non-permeable sealer locked-in the moisture.

“I said, ‘Well, we’ve got one shot to make this right.’ Let’s put down Miracote MiraPrime Aqua-Blok Xl and see what happens. To be honest, I didn’t think the results would be that positive,” Carver recalls.

MiraPrime Aqua-Blok XL is a clear, single-component, odorless, water-based penetrating colloidal silicate liquid primer that integrally waterproofs concrete, mortar and other cementitious materials. It penetrates deep into the structure to permanently enhance waterproof performance.

“We put the MiraPrime Aqua-Blok XL on and came back in about 36 hours to see if it had any effect,” Carver reports. “The concrete was bone-dry. This stuff really works. I said, let’s try another area. We got the same dry results. After six days the Aqua-Blok XL had reduced vapor drive from 99 percent to just 71 percent and dropping.

“That was unbelievable in so short a time,” he says. Carver had seen enough. He immediately authorized the removal of 6,500 square feet of surface material including the old sealer. Then his application contractor, Jeffco Concrete of Tuscaloosa, applied MiraPrime Aqua-Blok XL over the entire pool deck, followed by a coat of MiraFlor CQ Clear. MiraFlor CQ Clear epoxy provides long-lasting monolithic protection that is resistant to many chemicals.

The result? “The owner loves the refurbished deck,” Carver says. “I’ve been doing this kind of work for longer than I want to admit. I’ve seen products come and go. I’m very skeptical of what manufacturers say. I was skeptical the Miracote products would work, to be honest. This showed me Miracote goes beyond what even they think it could do. It goes beyond all expectations.” —Produced by Hanley Wood Strategic Marketing Services Group

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