Pool Plaster – Repair A Swimming Pool (2021)

There are two facts about swimming pools that you cannot deny.

First, swimming in a pool is fun, and a memorable moment.

Second, as a pool owner, it is extremely challenging to maintain a swimming pool.

However, the maintenance varies as per the type of in-ground swimming pool you own.

There are various kinds of in-ground pools on the market, like fiberglass pools, linear vinyl pools, and many more.

Among them, the cheapest type is concrete pools.

They are also known as gunite pools.

These swimming pools are the easiest to build, but the most difficult to maintain.

How can you build one?

The steps are simple, but they are not Do it Yourself (DIY).

Therefore, it is usually recommended to get it built by a professional.

Regarding the maintenance of this pool; it is extreme.

If you own this type of pool then you may face a large variety of problems that are damaging the pool.

Of course, there is a solution to every problem.

Similarly, there are various solutions to the problems that you may face regarding concrete pools.

However, only a few of them are effective in the long run.

Some solutions are a quick fix that will last for only a short period.

Thus, it is essential to be aware of the best solutions for pool plaster repair.

Do not worry.

Through our research, experience as well as sound knowledge, we have gathered the best solutions for the pool plaster repair.

Before we discuss the solutions, let us discuss the various types of problems that you can face with your pool.

Pool plaster – Basics

It is essential to understand the problems so that the solutions can be implemented effectively.

Usually, all gunite pools are covered by a thick layer of pool plaster.


Well, because concrete has numerous pores in it.

This increases the chances of leakage of water in the long run.

To reduce the leakage, pools are covered by a layer of pool plaster or POP.

Yes, you read that correctly.

In gunite swimming pools, the leakage of pool water cannot be stopped completely.

There will always be an amount of leakage.

However, through measures, you can control this leakage up to a certain level by maintaining the plaster in good condition.

Therefore, here is an in-depth analysis of each problem that you may face with a gunite pool.

Pool plaster repair – Crazing in the pool

Have you ever seen a cobweb?

This problem looks similar to one.

Crazing is a network of small cracks on the surface of the pool plaster.

These cracks are usually observable when the pool is dry.

Thus, there are very few chances that you could observe them when the pool is filled.

Since they are small in size, it can be difficult to identify them from afar.

They also have a darker color compared to the pool plaster.

Therefore, if you observe a dark line in the pool plaster, it is better to take a closer look.

You may face this problem almost twice a year.

Thus, it is recommended to check the pool plaster every month.

Now, do they increase the amount of leakage?

Yes, but that amount is very little.

However, it is recommended to solve this issue for the overall maintenance of the pool.

Plaster pool – Etching of the pool

Pool plaster

The large dents on the surface of the pool plaster are known as etching.

They usually occur due to a lack of calcium in the water.


Well, if the amount of calcium is low in the water, then it will absorb the calcium in the POP.

Thus, you will observe large dents in the swimming pool plaster.

There are limited ways to solve this problem.

We will discuss this in the next section.

Pool plaster patch -Spalling

This problem is also known as flaking.

In this issue, flakes of the pool plaster automatically peel off the pool wall.

The main reason behind this issue is the poor construction of the swimming pool plaster.

Thus, if the layer below the plaster is not settled properly, then it is more likely to happen.

This is the reason that we recommend only professionals should construct pools.

By doing so, you will automatically improve the durability of the pool.

This will also reduce the maintenance costs as well as effort.

Swimming pool plaster repair – Delamination

This is another problem that happens due to low construction quality.

This problem is similar to flaking.

However, it is an advanced version of it.

In this, the top layer of the pool plaster gets completely separated from the layer below.

Due to this, even a new layer of plaster gets washed away.

The washed away layer of plaster will likely be mixed with the water of the pool.

Thus, this problem can increase the chances of water contamination, by the plaster.

It can also increase the growth of bacteria as well as algae in the pool.

Therefore, this problem will give rise to a lot more problems, which will be more difficult to solve.

This problem should give you another reason to keep an eye on construction quality.

We will also discuss the solutions in the next section.

Pool plaster repair underwater – Fading

Fading means the dulling of color over a particular period.

You are most likely to see this problem in every concrete pool.

Usually, the color of the pool plaster fades away within six months.

So, is this damaging your pool?

Well, it is damaging the pool partially.

If the color of the plaster fades away, then it is likely that its cohesive properties are fading too.

Thus, over time you will start facing issues, such as flaking as well as declamation.

Therefore, it is highly recommended to solve this problem.

Now, why does this issue happens?

Well, there are various factors behind this issue.

However, it happens most likely due to a high level of chlorine in the water.

It can also happen due to direct contact with sunlight for a long time.

Plaster pool repair – Stains

There are high chances of stains on the layer of pool plaster.

The stains usually occur due to the regular use of various chemicals to treat the water.

They also happen due to dirt in the pool.

So, stains are bound to happen in a concrete pool.

However, you can control the stains in your pool.

Now, are they damaging to the pool?

Yes, they are.

Stains usually damage the strength of the plaster in the long run.

Thus, there are high chances of observing effects like fading of the plaster.

Do not worry; we will discuss an effective solution in the next section.

Chances of algae in the pool

The texture of a gunite swimming pool makes it vulnerable to algae.

What do we mean by that?

Well, the pool is most likely to become a new home to algae quickly.


The surface of the pool contains small pores.

Algae remain in these pores and keep on increasing.

Thus, there are high chances that even after treating the water; some algae remain in the pool.

These pools are also prone to the advanced version of algae that is known as mustard algae.

Underwater pool plaster patch – Techniques/Tips

Now, you are well aware of various problems that you will most probably face.

However, this does not mean that other problems could not occur.

The problems discussed are the most commonly faced ones.

Let us discuss the solutions to the problems discussed.

How to patch a concrete pool – How can you solve crazing in pools?

This depends on the level of crazing in your pool.

If the cracks are limited to a particular area of the concrete pool, you can try adding a little calcium to the water.

However, if the cracks are on the majority of the pool surface, then it is recommended to replaster the pool surface area.

Ensure that you plaster the pool without any contact with sunlight.

How to repair pool plaster – How to deal with etching on the pool surface area?

Etching most likely happens due to an imbalance in the water chemistry.

It is recommended to conduct a water test first.

Thus, you’ll know the level of elements in your pool.

After knowing the level, try to change the chemicals such that the water chemistry becomes balanced.

You can even brush your pool surface frequently to prevent this problem.

Ensure that you use an accurate pool testing kit.

A low-quality kit will give rise to more problems in the pool.

You must also not add salt to the pool for at least two months, to protect the pool plaster repairs.

Repair pool – How can flaking and delamination be solved?

There are limited effective solutions to these problems.

However, the most effective one is to focus on the build quality of the pool.

Ensure that the plaster, liquid cement bonder, as well the concrete, is of high-quality.

It is also important that the plaster is covered without contact with sunlight.

Plaster pools – How can you control the fading of the plaster of the pool?

The main reason behind fading is chlorine.

Thus, if you add a high amount of chemicals in the pool, it is likely to happen.

There are two solutions to this problem.

First, you can try to reduce the level of chlorine in the pool.

Most people do not prefer this method as it is time-consuming.

The second method is to drain the pool.

After, that clean the surface of the pool and re-fill it.

This is most likely to solve the problem.

However, if the problem remains, then it is recommended to carry out pool plaster repairs on the affected areas.

Plaster pool patch – How can stains as well as algae be controlled in the pool?

Have you ever wondered why stains happen even though you maintain the pool?

It is because you forget an important factor.

A gunite swimming pool is extremely sensitive to dust.

Thus, dust does not take much time to convert into a stain.

So, can a stain be removed?

Yes, it can be.

Usually, you can remove the stains by treatment with chemicals or acid wash.

If acid wash does not work, then use a stain removal kit.

What does it do?

These kits tell you the exact reason behind stains in the pool.

Thus, you will get a solution automatically.

It is always better to solve the problem before it happens.

Try to drain the pool frequently.

By frequently, we mean, at least once a month.

Of course, you can increase the frequency.

After draining, make sure to clean the pool properly.

You can even scrub the surface of the plaster.

However, it is recommended to use a soft cloth rather than a brush or steel wool.


Well, a brush can damage the plaster and can lead to delamination.

Another method to prevent stains is to cover the pool when not in use.

How will that be helpful?

That is simple; if dust does not fall into the water, then the chances of stains will significantly reduce.

These methods are even effective in dealing with algae in a concrete pool.

However, for algae, you can apply a paste of chemicals with the consistency of peanut butter on areas where algae are visible, i.e. after draining the pool.

Pool plaster problems

Here are the most commonly faced problems while doing plaster repair tasks.

Which tool to use to remove delamination?

Most people use the wrong type of tool to remove delamination.

What happens due to this?

Usually, this damages the pool more.

Repairing with the wrong tool can leave dents in the pool.

It can also increase the problem you are trying to solve.

So, which tools should you use to do a patch or other repair task?

It is highly recommended to use light tools like a putty knife.

Use tools that do not leave a mark after using them.

Usually, a light hammer and putty knife are preferred by most.

However, you can even use a medium-sized screwdriver.

Can a pool be plastered a limited number of times?

Most pool owners believe that they can patch the pool a limited number of times.

However, this is not true.

You can patch a concrete pool with new plaster as many times as you want.

However, pool plaster repair or using a plaster patch is recommended once a decade, at least.

Repairing pools – best practices

Here are some practices that will increase the durability of your concrete pool.

  • Use a testing kit frequently, and know the water chemistry.
  • Add chemicals to the pool as per the results of the testing kit.
  • Use a skimmer basket to remove the organic debris that is responsible for algae.
  • It is important to drain the pool frequently.
  • Try to cover the pool as much as possible.
  • Do a regular assessment of the condition of the plaster.
  • Even if your plaster is all right, carry out any necessary patch work after every 7-8 years.
  • Clean the pool after draining regularly.
  • Follow the procedure properly to deal with problems regarding the plaster.
  • Always maintain the level of salt in the pool.
  • Use proper tools to deal with problems related to plaster repair.

Plaster pool patch – Tools you can use

Here are some tools that you can use for plaster repair.

  • A light hammer
  • A medium-size screwdriver
  • Pool patch
  • Chemicals as per the pool test
  • A pair of gloves

Pool patch plaster – Frequently Asked Questions

Let us discuss the most commonly asked questions regarding plaster repair.

Can pool plaster be repaired?

Yes, pool plaster repair is easy.

There are various methods to repair plaster.

We have already discussed the most effective methods.

Above all, you need to identify the problem area in the plaster first.

We have discussed the types of problems you are likely to face in the plaster surface of the pool.

Some of them occur due to natural phenomena, while others are controlled by chemicals used to treat the pool water.

Ensure that you select the pool repair solution as per the problem.

The solution for delamination will not be effective for treating the fading of an area of plaster.

It is also recommended to use high-quality tools as well as chemicals for pool plaster repair tasks.

How do you fix a crack on the surface of the pool plaster?

A crack can become challenging to deal with.

It increases the level of water loss in the pool.

There are limited solutions to a crack on the surface.

Do not worry; we will not ask you to replaster the pool.


Well, that is a lengthy process, and expensive too.

If you are a pool owner, then you must identify each crack.

They usually appear almost every month.

Thus, replastering every month is something like a bad dream.

The most effective solution to this problem is to use a pool repair patch on the area affected.

These are plaster mix solutions that are formulated specifically to fill any type of crack.

How to use them?

First of all, you need to drain the pool.

Ensure that not even a single drop is near the crack or affected area.

You can even use a blower to get rid of the remaining water droplets.

Now, use the plaster mix to create a plaster patch. The consistency should be similar to peanut butter. Then apply it over the crack.

Make sure the plaster patch reaches every corner of the crack.

Let the plaster mix patch settle for a few hours.

There you go, the crack in your pool has been repaired.

If you are facing issues with using the patch, you can always read the instructions that come with the patch kit or crack filler you bought.

Can you repair the pool plaster underwater?

Are you looking for a method to solve a crack issue without draining the pool?

Well, here is one solution for you.

Try to make a solution of putty as well as plaster.

Make sure that both are used in equal amounts.

This patch mixture can be used to fill a crack without draining the water.

The only issue with this method is that it lasts for a short time.

Within a few weeks, the crack will likely open again.

You also need to know that most pool patch kits are not effective when applied to a surface covered by water.

Thus, if you want to deal with a crack in the pool, draining it and applying the patch to the dry surface area is the best option.

Why does delamination happen in pools?

The main reason is the construction quality of the pool.

It happens when there is an air void between the layer of plaster and concrete.

This leads to cracks, flaking, and delamination.

There are many other factors too which can affect the surface of a pool.

It can also happen due to low-quality plaster or concrete used to construct the pool surface.

Thus, it is highly recommended to always get the pool surface built by professionals.

If you are undertaking the replaster as a DIY project, then ensure you do it while protecting the repair area or patch area from sunlight.

The basics remain the same.

You need to check for delamination or signs of a crack in the pool area regularly.

Are gunite pools worth it?

The answer to this question depends a lot on your requirements.

Sometimes a fiberglass pool might be a better bet.

It also depends on your expectations of a swimming pool.

There are various types of pools on the market.

But a fiberglass pool and gunite pool models are two of the most popular choices.

Each pool has both merits as well as demerits.

However, let us discuss when you should consider a gunite pool and when you should not.

The first case depends on your budget.

Maybe you are looking for a swimming pool that is extremely affordable to build?

A gunite pool is the cheapest pool on the market at present.

The construction cost is almost half compared to the second cheapest pool.

Of course, due to this, even the maintenance cost is low.

However, the frequency of maintenance is high for these pools.

Are you looking for a pool that has a smooth surface?

Well, in this condition, you should not consider a gunite swimming pool.


It is because they have a rough surface.

Usually, a fiberglass pool is better if you want a smooth surface pool.

A fiberglass pool comes from the factory where it is made, so the surface is much smoother.