Consider all the options when choosing a pool finish.
By Christina DeMartinoDeciding which surface materials to use for a new pool is a lesson in compromise: you want a top-of-the-line finish, but there's a budget to think about. You want a finish that installs quickly but is durable enough to stand up to the punishment of a heavy-use facility. The choice you and your contractor make will be influenced by several factors: initial cost, ease of application, required downtime, regular maintenance, frequency of replacement, cost over the lifetime of the pool, aesthetics, effectiveness at creating a watertight shell, and the finish's resistance to water and chemicals. The real fun begins when you start comparing the different characteristics of each finish medium. Common surface options include plaster (marcite), fiberglass, sprayed liquid vinyl, exposed aggregate, tile and coatings paint). 'Every type of pool finish ever used has ultimately shown its own individual signs of wear and reaction to water and weather conditions," says Alison Osinski, owner of Aquatics Consulting Services, San Diego, CA.
Tile - Old, but Proven
Though most experts agree that tile is the best pool finish in the long run, it has its drawbacks. Compared to other methods, tile is initially very expensive to install. Kent Williams, owner of Kent Williams Consulting, Newcastle, CA, says it can be difficult to look at long-term cost factors when planning the installation of a pool. Tile is so much more expensive than other pool finishes that cost alone tends to keep people from considering it as an option. But, when you consider the life of a pool surface and how many times during the years a pool will demand major investment, tile becomes less expensive. "Tile runs approximately twice as much as just about any other finish being used today,' Williams says. 'But other than rerouting when needed, there is no telling how long it will last. I think we'll have to wait another 100 years or so to see if the file pools that are around now are still in working order.' Tom Griffiths, director of aquatics and safety officer for intercollegiate athletics at Pennsylvania State University, operates five pools - four indoor and one outdoor. 'All of our indoor pools are totally tiled,' he says. They are now more than 30 years old, and we haven't had any problems at all with them. With the exception of cleaning, they are maintenance-free.' One of Penn State's outdoor pools is concrete over steel. Griffiths reports that the outdoor pool has to be refinished or painted about every four years. Richard Fricker, president of Specialty Pool and Spa, Alpharetta, GA, warns against being "misled by the lasting benefits of tile.''It still must be cleaned and regrouted when necessary,' he says. 'It's just as important to have good water balance with tile as with other finishes.' The period of time between regrouting will depend greatly on the water condition, he says. 'Tile is great, but it, too, must be maintained, just like any other finish."
The Fiberglass Challenge
'Fiberglass is longer lasting than plaster, Fricker says. 'It is also easier to clean.' He warns, however, that fiberglass can be tricky to apply. If applied in- correctly, the fiberglass might not adhere to the pool's subsurface. Osinski agrees that proper application is extremely important when using fiberglass. The surface has to be properly prepared for the fiberglass to bond correctly. John Works of Pebble Technology, Inc., Scottsdale, AZ, grades fiberglass highest in aesthetics because of its bright, white finish, but agrees that it is much too early to know how it will hold up in the long-term. Severe weather can play an important role in fiberglass performance over time. Repeated freezing and thawing cycles can cause delamination. However, Osinski says that when properly applied, fiberglass is easily patched or recoated and is generally easy to clean. Fiberglass is also inexpensive compared to the alternatives, which adds to its popularity, she says.
So Why Plaster?
Although plaster finishes are maintenance-intensive, there are many still in service today. For almost 30 years this inexpensive pool finish was one of the few on the market; most other finishes simply hadn't been developed yet. Only in the past 10 years have newer products became popular enough for contractors to begin offering them. The lifespan of a plaster pool finish depends on how well it is taken care of, the condition of the water and the chemical balance used over an extended period of time. Fricker says a plaster pool can last from two to 20 years, depending on the chemical balance and the water conditions. Osiski notes that original plaster applications tend to last much longer than replaster jobs because the gunite, shotcrete or poured concrete pool surface is rough and porous, and forms a better bond with the plaster. White cement used to make plaster is non-porous, brittle and lacks strength. Crushed white limestone or marble aggregate are commonly added to the cement to make it stronger. Williams says he wouldn't recommend plaster for a refinishing job. 'Older gunite or concrete must be jack-hammered off in order for it to render an acceptably adhesive surface," he says. 'Cementatious mixtures must be precise in order for them to adhere to even a properly prepared surface. It's a very risky task.' Williams offers an additional warning about contractors offering lower-than-expected bids for resurfacing jobs: 'Skimping on proper preparation is the primary way contractors can make money. There are far more detailed specifications for preparation [of plaster finishes] than for the actual application."
Quartz aggregate was developed in Australia more than 20 years ago after contractors there obtained poor results with marcite and plaster products. Australian plaster had deteriorated faster than in other areas for several reasons: that nation's sand is of poor quality for mixing with concrete or bonding agents, much of the water in Australia is aggressive and acid rain is common. Quartz aggregate was discovered as an alternative. Prepared in a manner similar to terrazzo (a mixture of marble chips and cement), it is a combination of stone and cement. Its patented process was introduced to the United States just over 10 years ago. Works explains the product's advantages: 'Marble pebble is used instead of quartz. This makes a major difference with the polymer mix. Quartz is stronger than marcite but not as strong as pebble." The 'diamond" finishes now available on the market are similar and are applied with a similar technique. Whether it is patented or one of several similar products, the application process is very similar. These products can also produce different appearances with the addition of dyes to the mixture. Several color choices are available, ranging from light blues to greens to black, which produces a lagoon-like appearance when the pool is filled. Products referred to as exposed aggregate, quartz aggregate and pebble-surfaced all fall into this category. The medium mix, precise method of application and maintenance schedules will vary among products and brands, but on a long-term basis, they react similarly.
Paints and Coatings
The experts agree that paint and paint-like pool finishes require maintenance and rehabilitation. They respond negatively to chemicals, usually need re-painting every year, and - calculated over the life of the pool - can represent an unreasonably large expense. When many commercial pool owners chose these pool finishes, they didn't have the choices that are available today. Until they decide on major rehabilitation, they will need to continue to maintain the paint's surface.Osinski says new paint products available today are better than the older products. Some of these are called "coatings" rather than paint. They are more appealing from an environmental standpoint, less costly in the short-term than major rehabilitation, and are easier to work with than other paint products. The required downtime of annual painting can be a major problem. 'I recommend two coats of paint for an appealing result, Osinski says "Even though these new, faster-drying paints and coatings are designed specifically for pools, allow at least 72 hours between the coats." An additional factor to consider with paint products is that new paint may only adhere to older paint of the same type. Changing paint products midstream can be a recipe for peeling and chipping down the line. You should check with your paint supplier before switching paint products.
|Advantages and Disadvantages of Pool Finishes|
FiberglassDurability/Wear. Good. Up to 14-year guarantees offered on new applications. Long-term characteristics not yet reported.
Ease in Cleaning: New surfaces very easy to clean Stain-resistant and inhibits algae growth.
Aesthetics Stark, shiny finish produces an attractive result.
Non-slip Surface: Good to poor, depending on application. Can be extremely smooth, or 'roughed.'
Overall Advantage: Long-lasting easily patched or recoated and easy to maintain. Smooth surface retains heat and doesn't leak. Inexpensive compared to other alternatives.
Overall Disadvantages: Constant and extreme weather changes may result in delamination Color can wear off quickly, even if impregnated in the resin.
TileDurabinty/Wear: Superior to other finishes. Requires occasional re-grouting. Reported to outlast other surfaces.
Ease in Cleaning. Average when new. Superior to other finishes over the long-term. Doesn't require painting, acid treatments or other aggressive cleaning methods.
Aesthetics: As good as or better than other finishes. Overall appearance when filled depends on color of tile.
Non-slip Surface: As good as or better than other finishes. Grout at 1-inch intervals creates a superior non-slip surface.
Overall Advantages: Extremely durable with low maintenance. Stain-resistant, smooth texture while still providing non-stip advantages. Unlimited color choices. Good resistance to harsh weather and chemicals.
Overall Disadvantages: Initial cost can be prohibitive. Improper water balance can dull finish.
Durability/Wear: Poor. Most paints
require annual repainting. Chen-deals and water conditions adversely affect longevity. Ease
in Cleaning: Poor unless the paint is very new. Requires frequent, harsh chemical
Aesthetics: Good when new, deteriorates to poor as paint/coating ages.
Non-slip Surface: Poor unless non-slip granules are added to the paint
Overall Advantages: Quick inexpensive method of improving pool's appearance. Can be applied indoors or outdoors, and over wood, metal, fiberglass or concrete. Some newer coatings are environmentally friendly and more resistant to pool chemicals.
Overall Disadvantages: Commercial pools commonly need painting every year. Frequent downtime - several days - when new paint is applied. High maintenance cost over the life of the pool.
AggregatesDurabilaty/Wear: Very good. Long life expectancy compared to traditional pla& ter. Longer time span between recoatings.
Ease in Cleaning: Very good. Tight, polished stone finish prevents algae from sdeldng to surface.
Aesthetics: Excellent, with a large variety of colors available. Good for creating lagoon, ocean or other natural water body appearances.
Non-slip Surface: Excellent when applied properly Polished and tumbled stones create good, non-slip surface.
Overall Advantages: Variegated surface hides dissolved mineral stains and other cosmetic blemishes. Aggregates have a long life expectancy.
Overall Disadvantages: Application process is expensive. Quality of surface can depend on weather conditions during the application process. Improper application may result in overexposed stones falling out of the finish.
Christina DiMartino is a free-lance writer basedin Palm Beach, FL.
Reference: DiMartino, C. (1997). Aquatics International. The Right Finish Needs a Good Start. p.24-28.
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