Surface marks can appear in the plaster coating of a pool anywhere, but it isn’t necessarily a reason to worry. While leaking may occur in the pool, flaking plaster doesn’t mean that’s what’s taking place. First, let’s know what that plaster coating is. The plaster coat on a pool or spa is approximately 3/8 to 5/8 of an inch thick and is typically troweled over a 6 inch (or more) thick concrete shell of the pool when it is first built. Over time, the plaster is likely to fade, or even develop cracks, flaking or other visual differences. While generally, plaster problems are considered to be a maintenance issue; some would say that it is just part of owning a pool.

When leaks occur, they are often related to cracking in the pool shell itself. They are referred to as structural cracks. Plaster, however, is not a structural component of a pool or spa, meaning, it doesn’t make the pool or spa stronger. What is does do is it helps protect and preserve the structural part of the pool, i.e. – the shell.

flaking plaster

Many in-ground pool and spa shells are constructed out of concrete gunite or shotcrete, and a few out of masonry block or poured in-place concrete. These shells are solid, but not water proof. Though small, concrete is porous and water will slowly migrate or seep through the shells, it’s absolutely normal. To reduce that seeping water loss, a plaster coating is troweled over the shell to protect it from moisture seeping out of the pool.

If the concrete shell is not protected by plaster, the water migrating through the shell will cause deterioration of the concrete and that is when we see bigger problems, like structural cracking, for instance. It can be said that the plaster is protecting the concrete shell, much like how paint would be protecting wood from deterioration.

So does the flaking mean I’m leaking and seeping water out of the pool?

Not necessarily, but putting a microphone in the pool and listening at those areas of flaking and delamination, you can check yourself to see if the pool is losing water. If a pool is riddled with flaking and has happily survived for a decade or more, a complete resurfacing of the pool might be in order, replastering will definitely make the appearance of your pool more pleasant, but it isn’t a fix for leaks. In the short term, however, as small areas of plaster show their wear, you can make DIY repairs with some pool patch, follow the manufacturers directions.

The Aquafone LD is the homeowners leak detection kit providing DIY leak detection at your fingertips. If you called a leak detection company every time you suspected a pool leak, you be tens of thousands of dollars in the hole annually. With the powerful listening power of the Aquafone Underwater Microphone and hand-held amplifier, you can simply dangle the microphone into the pool and listen for water loss in any area in question. This includes those flaking areas in the plaster, as well as in the skimmer, at fittings and drains, suctions and along tile lines. Know your pool intimately and make repairs before small issues become big problems.

The Aquafone LD Kit comes with the Aquafone Underwater Microphone, the hand-held amplifier and headphones, two part concrete repair epoxy and a vinyl patch kit to stop the leaks you find and to enjoy your pool worry free.