Painting the Pool vs. Plastering the Pool

You've read of the new types of pool plaster options available, and had started looking into prices for resurfacing your plaster pool - when it hits you - what if I painted the pool? Painting pools has been an option even before pool plastering came around. Back in the day, all pools were painted; it was an annual pool opening tradition. When plaster for pools began to be used, pool owners appreciated the long lasting and durable surface and the smooth white finish. Should you paint the pool, or replaster the pool?

Longevity Factor:

Pool plaster will most certainly take this round. Pool plaster, when properly mixed, applied, cured and maintained - can last 15-20 years. Pool paint? Depending on the type of paint used, as well as application and curing factors, 2-7 years of life can be expected from a pool paint job. Round 1 goes to the scrappy young fighter's scorecard - pool plaster wins!

Durability Factor:

Paints used for pools, spas and fountains, are specifically made for underwater use, and are quite durable against poor water chemistry, temperature extremes and even rough treatment from pool equipment. Plaster however, with it's usual 1/2 inch thickness, can handle more distress than the thin layer of pool paint. Plaster wins again!

Prep Work Factor:

Both pool paint and pool plaster require that the pool be drained properly and prepared for the new surface. To paint the pool, you'll need to degrease the surface with TSP, then acid etch the plaster, followed by another washing and scrubbing with TSP. For acrylic pool paints, the pool can be painted damp, but for epoxy paints (the longest lasting pool paint), you'll need to let the pool air dry for 3-5 days before painting. Tape off the parts you don't want to paint, and you're ready to begin.

Pool plaster requires a much more industrial prep process. After draining, the "cut-n-chip" crew arrives, and with tiny saws, they cut the plaster beneath the tile and around all of the wall and floor fittings. Another crew arrives to acid etch the pool, to roughen the plaster surface, which helps the bond of the new plaster coat. Some plaster companies will make a third trip to apply a "scratch coat" - a rough, textured bond coat that adheres tightly to the old plaster surface, while giving a good surface for the new plaster coat to bond to.

Application Factor:

Once a pool is prepped and ready for paint, the pool painting process is fairly simple. Mix up your pool paint thoroughly and start rolling it on the deep end wall with a 3/8" nap roller, with a low nap. A 5-gallon bucket with a paint screen is best to move around with, as paint trays tend to spill. Using long, even strokes, apply the first coat, working from the deep end to the shallow end (don't paint yourself in!). After 4-6 hours, a second coat can be applied, which will require about half of the paint needed on the first coat. Dry time will vary, depending on the paint and outside temperature. Two to five days later, you can fill up the pool.

When pool plaster day arrives, a crew of 4-6 guys will arrive with a large plastering "rig", or a truck specifically designed for this purpose. One guy remains on the rig, and he mixes up the plaster mix; a mixture of white portland cement and marble dust. Additives for strength or color can be added to the mix at this time.

When ready, the mixer pumps the plaster mix through a thick hose, and the hose man sprays the plaster. With spiked shoes and a bullnosed trowel in each hand, they begin the process of smoothing the plaster evenly over the surface. They need to be careful not to overtrowel the mixture or to delay too long before troweling it smooth.

After 3-4 hours (these guys are fast), your pool will be plastered and a sock is wrapped around a garden hose left in the deep end of the pool. With the hose turned on, the pool begins to fill, without stopping, until the pool is full. You will be left with instructions to care for the water chemistry, and asked to brush the pool twice daily for two weeks, or until the plaster dust is eliminated.

If for no other reason than it's DIY, and pool owner friendly. Anyone can paint a pool. Pool plastering is not something that you should try at home, it is not DIY friendly.

Appearance Factor:

Both new plaster and new paint are looking good! Pool paint is shiny and reflective, and new plaster has a deep luster, like an eggshell. Of course, you can add colors and additives to plaster to create custom tones. You can do the same with paint, and could even paint a mural.

Plaster may look the best for longer, but at least initially, and for the first few years, the appearance of both is fairly equal. Plaster finishes, especially white plaster, can stain easily and look poorly after a few years. Painted pool surfaces wear-thin over time, and after 3, 4, 5 years, you can begin to see the sub-surface show through the thin spots.

Pebble plaster or plaster with quartzite flecks can help hide such stains. Colored plaster (black, grey, blue), where a tint is added, has a problem of highlighting calcium scale that deposits on the surface, which is nearly invisible on white plaster.

Cost Factor:

The cost of pool plastering starts at 4 thousand dollars, and can be much more if you choose strength additives and pebble or quartz surfaces. Price can be higher in some metro areas, and of course, for larger pools.

Pool paint is one of the most expensive paints I've seen, ranging from $50-90 per gallon. Depending on your size of pool, you may need 6-10 gallons, plus some painting supplies. If you paint the pool yourself, you will probably spend $800-900 on materials for the job.

But remember, pool plaster can last 3-4 times longer than pool paint! If paint lasts, say 5 years, and pool plaster lasts 20 years - they are almost equal in cost. In the long run, yes - but you can never be sure how long it will last.

Failure Factor:

Back when I was painting pools, we were very careful to prep pools properly and diligently. Nonetheless, about one out of ten paint jobs went bad. Soon after painting, we'd have blisters, or peeling and flaking paint. The result of a bad bond, or bad paint, or too much moisture in the air - never quite sure. But, the fact remains, not every paint job will be a success, and a few might even fail miserably.

Plaster jobs can fail too - small and big, there are lots of different problems that can occur with pool plaster. Spot etching - pits and pockmarks. Delaminations, where large sections fall off the wall, or lift up from the floor - bond failure. Depending on the mix ratios, application temperature and speed, curing, and chemical care after the plaster job - you may see variations in hue, streaking, or trowel burn. I have had almost an equal number (1 in 10) plaster jobs that have some serious defects, some to the point where we have had to re-plaster the pool, to keep the customer happy.