How To Fix A Crack In Your Pool Lining

How To Fix A Crack In Your Pool Lining

Fibreglass pools undoubtedly have the upper hand in terms of flexibility  when compared to concrete or cement-based products.

Fibreglass is also extremely durable and easy to maintain, but its appearance looks artificial and like plastic. Since the need for chemicals and scrubbing is much less, fibreglass is also, hands down, the more cost-effective option.

Even though small fibreglass factory-made splash pools are popular, occasional cracks and bulges are not uncommon. Here is what to do when you need to repair a crack in your fibreglass swimming pool. The same fibreglass materials are used during installation of a fibreglass lining inside a handpacked concrete or gunite pool shell.  

The Fibreglass Pool DIY Repair Kit

You will need the following suggested products to successfully repair a fibreglass factory-made pool or fibreglass lining: 

Drain And Inspect the Fibreglass Pool Lining

The first step would be to drain your pool of water to allow you complete access to the crack and the surrounding surface area for you to do an inspection. There are different ways to address the issue, depending on the severity, size and depth of the crack. Some cracks, like spider cracks, would not be something to lose sleep over. Contrastingly, structural cracks can cause more substantial problems if they are not addressed as soon as possible.

Minor Cracks

If you encounter minor cracks, sand the area and simply cover them with fibreglass paint and you are good to go. 

Severe Cracks

Unfortunately, if you discover that the crack is severe, the crack and surrounding area may need to be sanded down with a sanding disc. Using sandpaper as an alternative will not give you sufficient results and is thus not preferable. All loose particles will be required to be removed and the entire defective section will need to be replaced. Use a dry rag to thoroughly remove any sanding dust. It is strongly advised to include a swimming pool professional to complete the previously mentioned process. This will ensure that the crack is properly dealt with.

Apply The Bond Coat

The next step is to acquire a repair kit and mix the bond coat according to its instructions. Then apply the mixture to the crack using a putty knife to fill the gap. The aim is to ensure that it is in line with the pool surface. Now you have to wait for it to set (It should have a tacky consistency).

Note: If the crack is leaking water, first apply hydraulic cement before applying the bond coat.

Apply Polyester Putty 

Catalyse the polyester putty so that it can cause a chemical reaction. The higher the ratio of catalyst to putty, the quicker and the harder the putty will dry. Be careful to prepare the putty from the fibreglass repair kit according to the manufacturer’s instructions. With the bonding cement still slightly tacky, use the putty knife to cover the entire damaged area with an even coat of putty. You then need to allow the putty to dry completely. Once it has dried, use the sanding disc to smooth the area and use acetone to remove any residual dust.

Apply The Top Coat And Fibreglass Mat 

Paint a layer of the top coat from the fibreglass repair kit over the patch with a small paint roller. Cut pieces of masking tape, also from the fibreglass repair kit to a size approximately 6cm larger than the repaired spot. This has to be expanded in every direction. Carefully press the tape into the wet coat and immediately cover it with another layer of coating. Roll the patch thoroughly with the paint roller to press out air bubbles or other imperfections. Allow the coat to dry thoroughly before refilling your pool.

People also ask:

How often do fibreglass pools crack?

Not often. Most fibreglass pools do not even need repair work within the first 20 years. 

What is the best product to resurface a fibreglass pool?

If you are a fibreglass pool homeowner, the best product to resurface your pool is fibreglass, which is a polymer that is complemented by polyester resin. 

How many years does a fibreglass pool lining last?

Fibreglass pools are extremely durable and can last over 15 years. The top coat or lining colour will fade however over time and a re-coat is recommended after 10 years and to ensure the fibre mat is protected from water penetration.


Recommended products for minor cracks in marblite.

Cemcrete Under Water Pool Patch

Note that for small cracks in your concrete pool you do not need to drain the water. You can use this pool patch underwater or above water. Furthermore, it sets within 5 minutes.

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