How to Repair Plaster in a Pool

Is the bottom of your pool starting to feel like sandpaper rather than a smooth surface? Maybe you’re noticing more stains or rust on your pool’s plaster. Even though plaster is a common and durable material in inground pools, there comes a time when many pool owners need to repair the plaster in their pool.

Whether you’re trying to decide if you can tackle plaster repair yourself or if you’re better off calling a pro, I’ll discuss some repair steps and your options. Not sure if the plaster in your swimming pool needs repairing? I’ll also look at some signs indicating the need for repair.

Need To Repair Pool Plaster? Look For These Signs

Some pool owners don’t worry about the plaster in their pool until they see deep cracks or pieces of plaster missing. Don’t wait for extensive damage. If you notice these common signs, it’s time to think about repairing the plaster in your pool.

Stains

Most plaster pools are lightly colored, like blue, white, or gray. Discoloration or a “bleached out” look is common due to sun exposure or areas of heavy use, like the stairs. While the discoloration doesn’t necessarily indicate an issue, it may be time to repair if you want even color.

Stains are also common, and minerals like copper, calcium, and salt can create staining on your pool’s plaster. Other factors resulting in staining include organic matter like leaves from a nearby tree.

Excessive Roughness

When the plaster on your pool becomes rough, it’s best to consider repairs sooner than later. Not only is it annoying to walk across rough patches of plaster, but some spots can become sharp and cause injuries.

Every pool owner knows the importance of well-balanced pool water chemistry, but excessive roughness is often related to an imbalance in the water.

Peeling

If your pool has a low pH or calcium level, it dissolves the plaster’s material and is more challenging to fix. Pay close attention to your chemical levels to prevent this damage. As soon as you notice peeling, it’s time to take action.

Cracks, Thinning, and Chipping

More telltale signs that your pool plaster needs repairs include cracking, thinning, or chipping of the plaster. Small cracks may seem minor, but larger cracks that sprawl out like spider webs are nearly impossible to fix or fill. In most cases of a cracked or thinning plaster, it’s better to repair the plaster to avoid leaks or more significant issues.

Hire a Professional or DIY?

You’ve noticed cracks forming or significant stains and discoloration. Do you attempt repairing the plaster yourself or hire a professional?

Repairing gunite (also called shotcrete) is often an involved process, so the decision comes down to your budget, the severity of your plaster problem, and whether or not you have the time to do the project yourself. Let’s take a look at the pros and cons of both options.

Hiring a Professional

Many pool owners won’t even think twice about hiring a professional specializing in plaster repair. It might be your best option if you have a budget for professional services.

Hiring a pro often means the job will get done right, relatively quickly, and many companies offer some warranty. The downsides include a long wait time depending on how busy they are or hiring someone who doesn’t do as good of work as they claim.

If cost isn’t a determining factor and you want to spend more time in your pool swimming than doing a DIY project, professional repair is probably your best option.

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Choosing DIY Options

Want to repair your pool’s plaster yourself? This is not an impossible job. Many pool owners do their own pool maintenance, which includes bigger tasks like repairing plaster.

Like any DIY project, you want to make sure you have a plan and all the tools you need, and fully understand the process before you jump in and start making repairs. You’re likely to cut costs if you repair the plaster yourself, but only if you do it correctly. We’ll help you figure out how to do just that.

Supplies for Repairs

If you plan to repair your pool yourself, you’ll need the proper supplies and gear.

Since plaster repairs involve chemicals, it is crucial to have goggles, gloves, and face masks to work safely with an acid wash.

While you might have some of these tools at home, you’re likely to need:

  • Shovels
  • Hammers
  • A hose
  • Buckets
  • Chisels
  • Putty Knives
  • Air compressor
  • Power trowel
  • Power sander
  • Cement or mortar mixer

You might also need a cleaning solution, plaster mix, and bond coating. If you don’t have specific tools, like a cement mixer or power sander at home, check out your local rental store to see if you can rent rather than buy.

Repairing Plaster In an Empty Pool

Plaster repairs are almost always easier in an empty pool, so if your pool is drained, you’ve already made your DIY project a little easier.

Preparing Your Pool

The first step is to drain your pool if there’s any water left in it. To ensure everything is clear, remove any loose debris in the area. This is a good time to chisel out any worn-out plaster, smooth out rough spots, and clean the area you will be repairing.

Read my article on pool plaster prep for a full breakdown of all the steps.

Before You Plaster

Before adding a new plaster layer, you need to use your chemicals to remove the old plaster application. The easiest way to remove the old plaster is by brushing the areas with your acid wash.

Next, thoroughly wash the acid wash away with a hose. Make sure it dries off before proceeding to the next step. When the area is dry, apply a bond coat over the spot and wait for it to dry completely. The bond coat usually takes about eight to ten hours to dry.

Applying Your Plaster

Depending on how much of your pool you need to repair, the prepping process can take a long time and might span into a few days or a few weekends if you are a “DIY Weekend Warrior.”

Once the pool is prepped, it’s time to mix up your plaster. Use a cement or mortar mixer and follow the directions on the plaster packaging. I recommend mixing up smaller batches of plaster as you go rather than one large batch that you might not end up using.

When you’re ready to prepare your pool surface with the plaster, start working at the deeper end of the pool. Using your power trowel, apply your plaster at least three-eighth of an inch thick, and smooth it out to help it cover up all crevices. Then, let the layer of plaster dry.

Once that plaster dries, apply another layer over it with a thickness of one-fourth of an inch. Be sure to look over the area to see if all your plaster is uniform and smooth. Allow enough time for this layer to dry. Reapply if necessary.

Try working in an ideal temperature between 50 to 70 degrees Fahrenheit for the best work results. This ideal temperature ensures your plaster won’t dry too quickly and create unwanted cracks.

You can read my complete article on the pool plastering process for a more in-depth look at all the steps.

Adding the Finishing Touches

After letting your last layer of plaster dry completely, paint over the area with some pool paint to make it blend more evenly with the rest of your pool. I recommend starting with two coats of paint, letting it dry, and seeing if you need more. After the paint is dry, you should be ready to refill your pool. Don’t re-enter your pool until the water is balanced and all work areas are clear of plaster dust.

Repairing Plaster Via Patching

If you have smaller areas that may need repairing, a pool patch repair kit may be an excellent option for you. This method works similarly to traditional plastering techniques, but is suited for smaller calcium scale repairs. Patching techniques encourage tight and durable layers of plaster for cracked or brittle areas of a surface.

When patching, you’re encouraged to drain your pool below your target repair area and remove any loose cement on the surface of your pool floor. Once the plaster is mixed to your preferred density for patching, you can apply it to any cracks you might see.

If you run into air bubbles when patching, use your equipment to release them and smooth out the plaster.

Repairing Plaster in a Full Pool

Although traditional plaster repairs recommend that you work in an empty pool, some patching material for fixing small cracks and dents works well on full or partially full swimming pools.

Setup

First, you need to find your cracks and holes and assess the size of the damage. If the damage size is surface-level or not too deep, repairing in a full pool should be relatively easy. If not, you might be better off draining the pool.

Once you identify the damages, you should do your best to remove worn-out plaster and debris from the area you cleaned.

Next, mix epoxy and apply it to the cracks to patch them up and keep them in place. Plaster can also work as a patching alternative if you don’t have any epoxy. There are plenty of repair products, like Aquabond, that are specifically designed for underwater repairs.

Applying the Patching Material

Once your patching material is mixed, shape the plaster patch to fit into the crevice. If you are trying to fix cracks, mold it into a tube-like shape. Roll the plaster into a ball if you’re repairing a small hole. Once you’ve molded your plaster, press it into the cracks or holes.

After pressing down your material, take a trowel, smooth out the top of the mix, and fill in the surrounding spots of your repairs. Once you check to see if everything is secure and complete, you can let the material dry and keep your pool in good condition.

When working with plaster repairs in a full pool, this option works best if there is minimal damage to your plaster, and if it is dealt with quickly. If the damage is too deep or excessive, you may want to skip doing this set of repairs in a wet pool and consider draining it dry for the appropriate type of repairs.

Final Thoughts

If your inground pool has cracks and other damage, you want to repair it quickly to prevent water leaks, structural damage, and even injuries. Fortunately, fixing the plaster in your pool doesn’t have to be complicated. Use these tips above to determine when DIY repairs are possible and when you’re better off calling a professional.

Knowing the difference between the two types of repairs means you can quickly get your pool back in great shape so you and your family can enjoy swimming again.

Have questions? Feel free to shoot me a message. Always happy to help.

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