Pool Plaster Repair: How to Repair In 6 Easy Steps



No one knows how it happened. Maybe it was the overzealous game of pool volleyball last week or maybe it was the Tonka truck your kid brought into the pool against your wishes. Either way, now there’s a crack or gouge in your pool plaster that needs to be fixed.

It’s important to address damage to your pool as soon as possible because what begins as a small plaster crack could soon become a more extensive (and expensive) leak. But before you panic and call a professional, take a deep breath. Depending on the size and depth of the damage, you may actually be able to repair it yourself pretty easily. 

How to Repair Plaster in Your Pool

If you’ve ever spackled some holes in the drywall before moving out of an apartment (to try to save your deposit, right?) you already have the skills necessary to repair the plaster in your pool. 

But even if you’ve never had to patch drywall holes, you’ve come to the right place. We’ll walk you through it step by step.

Let’s start by gathering all the materials and equipment you’ll need to get the job done. If you don’t have some of these items, make sure to grab them before you start the project.

Materials You’ll Need

  • A submersible pump and drainage hose (to drain your pool)
  • A hammer
  • A masonry chisel
  • A pair of large pliers
  • A pool trowel or putty knife
  • Some grouting sponges
  • A wire brush
  • A small, soft-bristled paintbrush
  • A spray bottle of water
  • A garden hose (that’s long enough to reach around your pool)
  • A spray nozzle for your hose
  • Some underwater sealer
  • Some pool plaster
  • Epoxy putty (for underwater use)
  • A pair of swimming goggles
  • A safety mask (so you’re not breathing fumes or plaster dust)
  • Ear protection
  • A set of safety goggles
  • Some heavy-duty work gloves
  • The proper attire (long pants, long-sleeved shirt, acid-resistant boots)
  • Some old towels or rags

Hey You! Just a quick note: if any of this sounds intimidating or you don’t feel comfortable working with these materials, it might be a smart idea to call a pro on this one. It’s better to be safe than sorry. However, if you’re a DIY master and home repairs are old hat for you, read on!

Okay, you have all of your equipment and now you’re ready to get started. You’re about to earn your merit badge in pool plaster repair.

How to Repair Plaster When Your Pool is Empty 

With a drained pool, you can easily get in there and take care of the damage. However, without the water, there are more opportunities to damage the rest of the plaster. The pool is meant to be full of water and anytime it’s not, you’ll need to be careful to protect your pool. This means not using your empty pool as a skate park or half pipe. 

Speaking of protection, whenever you’re flexing your DIY skills, you want to protect numero uno first: that’s you. Always wear eye protection, ear protection (whether they be plugs or muffs), and it’s a good idea to have a full face shield too. 

Step 1: Find the failing spots 

You can use a chisel and hammer or some rougher tools knock out the old plaster. We’re going to be replacing it, so we want to make sure we get all the loose stuff that’s no longer working out of there. Scrape it all away and knock it out.

Step 2: Cut out the broken bits

After you get the obvious spots, take a piece of wood or the wooden handle of your hammer and tap around the area of the obviously-damaged plaster. If you hear a different hollow sound, then chances are you’re going to have to dig out the plaster there too. That’s an indication that there are some air bubbles where the plaster has failed and become disconnected. 

You’re going to have to knock and chisel these areas as well. 

If your plaster looks a little worse for wear, you may have to cut out the deteriorating parts. If you have to do this, you can cut into the plaster at an angle to create a clean spot to patch. 

Step 3: Clean it out

Now that your pool is full of holes and divots, it’s time to clean them out and prep them for filling. 

Rinse out the areas you’ve just chiseled and cut, and let them dry. Once dried, you can use a dry paintbrush to get the last bits of dust out. The more foreign material in the cracks, the less effective the patch will be. 

If you have an air compressor you can also go around and give them a quick blow out to really remove all of the dust. 

Step 4: Mix it up

Every patch and plaster will have slightly different directions, so it’s always best to follow the instructions that each manufacturer provides. 

Make sure you mix enough to fill all of the cracks and divots you have. You’re going to want to do this all in one go. You’re going to be fighting with the clock if you have to stop halfway through to mix more materials. 

When mixing, the goal is a thick paste consistency. It shouldn’t flow but it should still be easily spreadable. 

Step 5: Fill it

Dampen your surface area you’re working on, and then go ahead and start spreading it into the cracks and holes. A putty knife or trowel is going to be your best friend here. Keep everything slightly damp and make sure you squeeze out any air bubbles from the holes. 

Remember when I said you’re going to be on the clock after you mix? That’s because you’re going to need to keep everything damp while you’re filling in your cracks. If they dry out, the plaster will likely shrink and leave you with more problems. 

So move quickly and efficiently, keeping a damp towel over your plaster until you’re ready to fill the pool back up. It may seem counter-intuitive, but the patches will actually cure better underwater.

Step 6: Set it… but don’t forget it. 

Keep an eye on your handiwork as you fill up your pool. If it’s taking a while and drying up you can wander around with a spray bottle to give it a quick spritz to keep it moist while the pool is filling. 

How to Repair Plaster When Your Pool is Full

If you have a crack or hole that’s not too big (or not too deep) you might not have to drain out the entirety of your pool. 

You actually have two options for materials to use and both work just as well.

The cleaning and prep steps are going to be the same for both options. Grab a set of goggles and maybe even a snorkel. You don’t need anything fancy, dollar store brands work just fine.

You’ll want to scrape away at the crack and dig out any of the loose bits of plaster and gravel. After you’ve knocked out all the loose bits, you can take a wire brush and give it a good scrub.

Now you’re ready for your filler. 


Epoxy comes in two parts that need to be mixed together before it sets. The first is the actual putty, patching ingredient. The second is the hardener that makes it stiff. Follow the instructions on the epoxy to prep it. Most use a 1 to 1 mixture.

Wear some gloves and mix it up


Plaster works in a similar way to epoxy. Make sure you get a brand that specifically mentions that it works for use underwater. 

Follow the manufacturer’s instructions to mix. That’s it. Pretty easy, right?

Now that you have either a blob of epoxy or a blob of plaster ready to go, it’s time to actually patch the hole. If you have a crack you’ll want to make a noodle out of the plaster just like you used to do with playdough as a kid. If it’s a hole or gouge, you’ll want to make a ball that’ll fit into the hole.

Dive down and press it in so that it spreads throughout the hole or crack and try to work it into every crevice. 

The final step is to take a plastic trowel and scrape over the top. This will press the remaining epoxy/plaster into the problem spot and remove any excess.

Actually Replacing Plaster In Your Pool

If worst comes to worst and you actually have to replace significant portions of plaster in your pool, the time has come to hire a professional. Maybe you let some of those cracks sit too long before attempting to repair them or maybe your whole pool is just in need of a facelift.

Either way, if large sections of your pool plaster are damaged or a lot of plaster needs to be replaced, it’s much safer (and cheaper in the long run) to hire a professional to do the work for you. Even if you feel confident in your concrete and plaster-working skills, pools are a different beast entirely from concrete-pouring at a construction site. 

Save yourself the headache and future expense of having to hire a pro to fix your botched attempt. It will be safer for you and better for your pool in the long run.

Get Plastered!

See? That wasn’t so bad! All of the damage is repaired and your pool is freshly plastered and ready to swim in. Now you can dive in knowing that there won’t be any leaks lurking in the shadows to surprise you down the road.

After this, you can say that you’re an experienced pool repair DIYer with the know-how to patch any plaster cracks that might pop up again in the future. Your handy skills with small repairs will save you big bucks on what might become larger repairs and help to keep your pool safe, full of water, and perfectly swimmable for years to come. 

Categories: Pool Care, Pool Problems