Fiberglass Pools


Fiberglass pools are not new; in fact these types of pools have been around for nearly 50 years. Fiberglass pools are one piece, factory built shells made with fiberglass layers, resins, and finished with a gel coating, a non-porous surface similar to cars, boats and pool slides.

Fiberglass pools are available in a wide variety of shapes and sizes with various tile patterns, fiber optic lighting, and in-floor cleaning systems, possible. Some forms of maintenance like acid washing, resurfacing, and liner replacements don't exist with fiberglass pools, but proper weekly chemical and cleaning maintenance are still needed to protect the gelcoat finish.

Water Level

Do Not Drain Your Pool! A fiberglass pool is designed to remain full of water at all times. If the pool is drained without proper directions, water or ground pressure outside the pool could cause the structure to buckle or crack, or even pop out of the ground, partially or fully.

If it becomes necessary to drain the pool, for pool repairs or to replace the water, you can contact a builder or service company to take the risk, or take the risk on yourself. It’s not an absolute certainty that damage will occur when draining a fiberglass pool, especially for those with equipment and knowledge to get the job done safely and quickly.

For best operation, keep the water level in the center of the rectangular skimmer plate on the pool wall. Low water level may cause the circulating pump to lose prime resulting in pump damage; high water level reduces or eliminates the skimmer effectiveness.

Fiberglass Pool Surface Care

The "bathtub" ring which forms on the pool wall or tile caused by body oils, suntan lotions and air borne contaminants can easily be removed with swimming pool tile cleaner or other non-abrasive commercial tile or vinyl cleaners. Do not use abrasive cleaners, steel wool, metal scrapers, brushes or tools as these may cause permanent damage to the gel coat finish.

The gel-coat finish of your fiberglass pool can be scratched like any other gloss surface. The gelcoat is seven to eight times thicker than a normal coat of paint so it is not likely that scratches will be more than superficial.

Dull and faded gel coat at the water line may be restored with a heavy cut automotive polishing compound either power or hand applied followed by a coat of wax. If that doesn’t help, you can install perimeter pool tile to a fiberglass pool, by using silicone adhesive and silicone grout.

Fiberglass Pool Surface Cracks

Hair line cracks, also called crazing which may develop over a period of time are not uncommon. They only penetrate the gel coat and do not affect the pool's structure or result in leakage. Scratches and hair-line cracks are repairable. The surface can be prepped and re-gelcoated, or for very small or isolated cracks, an epoxy filler can be used for quick underwater repairs.

Cleaning a Fiberglass Pool

Most of the dirt and debris that sinks to the bottom of your pool can be brushed toward and into the main drain and will be trapped in the filter. Heavy amounts of dirt and debris should be vacuumed out manually or with a pool cleaner. Use a pool cleaner that is suitable for fiberglass pools.

With a fiberglass pool surface, you are best using cleaning tools that are softer, hose that are made for vinyl pools. You can use a wheeled vacuum head, but don’t use a steel bristled brush, only nylon or plastic bristles.

Stain Removal on a Fiberglass Pool

Acid washing a fiberglass pool is not recommended, nor is it very effective. Fiberglass pools are very stain resistant because of the ceramic like finish. If you experience berry stains or leaf stains, clean the pool, balance the water and shock the pool while filtering. Brush areas where the stain persists, and sprinkle some chlorine pool shock or Stain Free (ascorbic acid) over the stained area.

Most stain removal chemicals can be safely used on fiberglass pools, but be sure to read the label. Remember not to scrub hard with something that may scratch or rub off the gelcoat surface.

Pool Water Chemistry

When tests show the pH, Total Alkalinity and Calcium Hardness are in range, The pool is said to be in balance. Balanced water will be clean, clear, blue and sparkly. Eye and skin irritation will be reduced, and pool equipment and gel coat surface life will be extended. Balanced water improves sanitation effectiveness and reduces or eliminates the necessity of adding costly water chemistry supplements.

Prolonged improper water chemistry and high sanitizer levels can lead to pool equipment and gel coat damage which may not be covered by your fiberglass pool warranty. Test your water weekly and add adjustment chemicals to keep the water balanced and sanitized. This is the number one thing to protect the surface of a fiberglass pool.

Fiberglass Pool Installation Procedure:

  1. You or your dealer will mark the site for the new Fiberglass pool. You should think about sun exposure, access to a bathroom, areas for guests to gather (and to retreat from the afternoon sun), and access to the site during construction. In general, people will gather on the side closest to the house at the shallow end of the pool. Once the outline of the pool is marked with chalk or spray paint you are ready to dig the hole.
  2. The next step will be to dig the hole according to the fiberglass pool's dig specs. This step will take 3 - 6 hours and varies in complexity with the size and shape of the pool. Sport Pools with flat bottoms are the easiest to dig. Deep well pools or those with several depth levels are more difficult. The key to a good hole is to measure frequently. You will use a builder’s level (transit) to measure as you go. These laser levels can be rented, to take the guesswork out of measurement. Once the hole is complete, strings are used to set the exact grade for the pool. This string will also act as a guide when you backfill the hole with sand or gravel.
  3. The Fiberglass pool will arrive on a flatbed truck at your home, ready to install. Now is this is where the real fun begins! The pool is lifted off of the truck using a boom truck or, in the case of smaller pools, an excavator or large trac-hoe can lift it off. You or your dealer will now need to level the pool to less than an inch. This can become a little monotonous for a first time installer. Raise that end up, now this end is too low, then the sides are off. You should get this done in well under the typical 3 hour minimum for the crane. The water will seek its own level once the pool is filled. For this reason, you need to pay close attention now.
  4. Ok, it is now time to plumb the Fiberglass pool and ready it for back-filling the hole around it. You or your dealer will drill two to four 2 in. holes for the returns, and optional light or automatic cleaner. If you ever plan on installing an automatic cleaner, go ahead and plumb for it now. It can always be added later. Plumbing is as simple as gluing the PVC pipe. Connect the pool and power to the filter for both the electrical and plumbing. This can take 3 - 5 hours.
  5. You will also start filling the Fiberglass pool with water. Each pool has a level to which it can be filled with water with no backfill around it. If you use a fire hydrant or a water truck, filling is fast. The water must remain about 12" higher than the surrounding backfill. This helps maintain the shape of the pool.
  6. Rough grade is easily done with the right tools. You can either rent a small Bobcat with a landscape box, or hire someone to prepare your yard. In either case, you will want to be sure that the pool is at a local high point in the yard. Be sure that all of the ground around your Fiberglass pool slopes away from the pool. Typically you want 2" - 6" of rise at the pool edge, relative to the surrounding area. This allows rain water to drain away from the pool.
  7. There are two options for pouring the deck: standard and cantilever. In a standard deck, the concrete come up to the edge of the Fiberglass pool, leaving an exposed band of fiberglass around the pool. In the cantilever deck, the concrete is poured up to and over the edge of the pool. When combined with tile, this is a very striking finish. There are many other choices: stamped concrete, slate, rock, washed aggregate, brick pavers, cool deck, and the list goes on...
  8. One final note before we wrap up. It is often better to wait a few weeks before actually pouring the pool deck. The reason is that the area around the Fiberglass pool will settle over time. This is highly variable due to various soil conditions, rain levels, and backfill material. During that wait, your pool is completely ready to swim.

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