Can You Have an Above-Ground Fiberglass Pool?

close up of fiberglass pool

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An above-ground fiberglass pool, which is a pool shell reinforced by fiberglass, might seem like a great option for elongating the lifespan of an above-ground swimming oasis, but you'll need to think twice before committing to this plan.

Fiberglass pools are a unique alternative to the standard metal above-ground pool. They offer many more options for customizations for shapes and have a unique smooth texture that other types of finishes and pools can’t replicate while offering a long lasting surface than its liner counterparts. With proper planning and consideration to the fiberglass it can be a wonderful alternative to your standard edition above or semi-above ground pool.

Here's what you need to know about the possibility of having an above-ground fiberglass pool.

What Is Fiberglass?

Fiberglass is exactly what it sounds like — very small fibers of glass. The most common use of fiberglass is to add strength to an object. Usually fiberglass fibers are arranged in a pattern similar to a woven basket and laid on top of a backing, then coated with a polymer to adhere the two materials, making for one very strong, lightweight structure. Fiberglass is also an excellent choice if you need to reinforce an irregular shaped object or pool that would either be hard to form with a more traditional material. Fiberglass also doesn’t wear as easily as traditional pool coatings making it a unique and beneficial choice for pool construction.

Why Fiberglass Pools Can’t Be Above Ground

While fiberglass is incredibly strong, over time the weight of the water in the pool will make the fiberglass flex and crack. A pool has people constantly jumping in and climbing on the sides, moving the water and creating pressure on the side walls that the fiberglass shell will have to endure. Due to the nature of fiberglass, once it cracks the strength is gone, and there is no “patch” for fiberglass like liner or other hard surface pool types.

Additionally, this added movement that happens in a pool allows the fiberglass to separate from its backing. Once this happens there is no way to properly repair it. It is for this reason that no matter what application a fiberglass pool is used for, it must be reinforced with backfill to limit flexing. Fiberglass pools are more susceptible to irreparable damage due to the nature of fiberglass itself. Because of the inflexibility of the sides and inability to be patched, fiberglass pools should not be installed completely above ground.

Alternate Types of Above Ground Pools

Besides fiberglass there are a number of alternate types of pools, all with certain pros and cons depending upon your specific circumstances. For instance, if you want to try pool ownership and don't want the huge upfront cost that comes with most types, an inflatable pool might fit the bill. Inflatable pools have come a long way from the times of the small kiddie pools in the back yards. Larger sizes now come with their own cartridge filters, pumps, and PVC frames to mimic their bigger aquatic siblings. This is the perfect “starter pool” to see if pool ownership is right for you, but it leaves you with little options to customize.

If you are looking for a more standard option, then the traditional metal or hybrid pool would be perfect. Traditionally, above-ground pools have been constructed of a rolled steel pool wall with top and bottom tracks and aluminum supports and outriggers. In recent years, the aluminum supports have been replaced with plastic, partly because plastic resists corrosion better than metal. Both of these pool types use a traditional liner that is available in many styles and designs but have a hefty upfront cost due to materials and necessary groundwork. There is also such a thing as a precast concrete pool but this requires heavy machinery to install and deliver. Also, if made of more than one section, the expansion joints usually fail over time (chlorine attacks the joint material). As a long term investment these types of pools are incredibly tough to repair because of the possibility of cracking the entire concrete casting.

Installing a Fiberglass Pool Partially Above Ground

If you are set on your pool being an irregular shape, want a pool that does not need to be resurfaced every 10 years, or want a pool built into a hillside, you can still have a partially above-ground fiberglass pool. This is installed the same as any other partially above-ground pool, but it must be backfilled and framed into a box to hold the backfill. This box will stop the flexing of the fiberglass and add to the already strong profile of the pool.

As with any pool it is important to make sure the selected location is acceptable for the pool install. Do all groundwork first to make sure that the pool will stay level for its life expectancy. Remember, with fiberglass it is very important to limit flexing as much as possible.

Once the groundwork is completed and leveled, it’s time to drop the pool in. Fiberglass pools are pre-formed in a factory and shipped in one solid piece. They arrive onsite with a trailer and get lifted with a crane into place just like a modular house. After the pool is set in place, holes are cut (if not already present) for skimmers, returns, drains and any accessories and installed around the pool. When the plumbing is completed, the final step is to backfill very carefully and evenly as to not put excessive pressure on the pool walls.