How To Repair A Fiberglass Pool

Fiberglass pools are very popular because they’re durable, easy to install, and require minimal maintenance. But just like all other types of pools, fiberglass pools can get damaged. You may face leaks, cracks, or discoloration, for example.

Fiberglass pool issues vary in terms of their solution. Spider cracks may need resurfacing to restore aesthetics, while wider cracks need binders like epoxy resin. For discoloration, you’ll need refinishing. Pool leaks may require repairing the plumbing system as well. 

When it comes to the issue of repairing fiberglass pools, you may need to hire an expert for the job. After all, you don’t want a problem to get worse and cause an even bigger headache. Let’s take a look at some common issues with fiberglass pools and how you can address them.

Do Fiberglass Pools Need Repairs Over Time? 

New modern fiberglass plastic swimming pool entrance step with clean fresh refreshing blue water on bright hot summer

Fiberglass is naturally more flexible and durable than many other pool materials. That explains why they require far less maintenance compared to other pools.

Most fiberglass pools can last between 20 and 30 years without needing any repairs. A fiberglass pool doesn’t need resurfacing like concrete pools do. 

A concrete pool has to be resurfaced every 10 years. A fiberglass pool, when fitted with modern technology like gel coat and resin technology, is far more resistant to wear and tear and corrosion than a concrete pool.

However, a situation may arise that will force you to repair your fiberglass pool. In such a situation, you’ll probably have to call an experienced contractor for the job.

Common Fiberglass Pool Repairs 

Some of the issues that occur with fiberglass pools are spider cracks, wall bulging, discoloration, and leaks.

Spider Cracks

Spider cracks can be hard to notice, even if the pool is empty. This is because they are tiny cracks that occur in the gelcoat, or surface layer, on the fiberglass.

Naturally, spider cracks aren’t structural, so they won’t affect the functionality of your pool. These cracks result from pressure exerted anywhere on the pool shell that exceeds the ability of the gelcoat to flex. 

The most common causes of such pressure are improper installation, incorrect manufacturing, or incorrect shipping. In most cases, the cracks occur as a result of human error during installation, especially when the technician is attempting to level the shell.

Though these cracks don’t pose any structural threat to your pool, you can choose to repair them to improve the appearance of your pool.

Wall Bulging

Pool wall bulging is very rare, as long as proper manufacturing and installation processes are used. In most cases, the backfill material (mostly sand) is the cause of this problem.

The sand itself might not be an issue, but when it gets wet and liquifies, it can exert too much pressure on your pool wall, causing it to bulge, particularly if the pressure from the heavy liquified sand is greater than that of water in the pool.

The only solution to this is to replace your backfill material. The best material to use is gravel. The properties of gravel don’t change even if it gets saturated with water.

The pool should also be designed such that it’s strong enough to withstand excessive pressure from the water inside it and the backfill material.


Just like the spider cracks, fiberglass pool discoloration isn’t a structural problem but instead an aesthetic issue. With time, the gelcoat on the surface of the fiberglass will fade. But you can delay this by maintaining the pool properly and ensuring you balance the chemistry of the pool water.

When your fiberglass pool is discolored, it doesn’t mean you have to replace the entire pool. All that is needed is a refinishing and the pool will look brand new.


A leaking pool is an indication that there’s a problem with your plumbing system around the pool. In most cases, erosion occurs when the backfill material settles and, in the process, damages the plumbing system.

For example, if you use sand backfill, it will exert downward pressure on your plumbing pipes as it settles. This can cause damage, particularly to the joints.

The solution to this problem is to replace your sand backfill with gravel. Gravel doesn’t settle as much as sand. Therefore, it will not affect your plumbing system. The plumbing system must be repaired after the sand is removed and before the gravel is added.

Fiberglass Pool Maintenance

Swimming pool and deck

Fiberglass is a low-maintenance material, but that doesn’t mean you should neglect your fiberglass pool. Some of the maintenance practices you need to undertake include:

  • Cleaning the pool: If you notice any floating materials like bugs or leaves, you can clear them away using a skimming net (on Amazon). Also, clean the bottom surface of the pool and the wall to prevent algae growth. 
  • Check the pool chemistry: Some of the pool water chemistry parameters you should keep under check are total alkalinity, cyanuric acid level, calcium hardness, pH, and chlorine level. Always use the right chemicals to balance these parameters.
  • Run the pool filter: You need to run your pool filter once per day to keep the water clear and clean. The hours to run the filter can be calculated using the formula: hours = pool volume/filtration rate.
  • Maintain the water level: The water level in the pool should always be above the skimmer. If you have to drain the pool, call an expert; don’t do it yourself.


Fiberglass pools are among the most customizable and rewarding ways to improve your backyard. Fiberglass pools are less likely to be damaged and much more durable than other types of pools.

While they have a higher initial installation cost, their low maintenance requirements make them well worth it in the long run. A fiberglass pool is a lifetime investment and a permanent source of delight, beauty, fun, and relaxation.

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