Concrete Pool Deck Cracks: Causes, Types, Repair Methods
You don’t have to spend a ton of money to have a beautiful deck around your swimming pool.
Concrete pool decks are affordable, relatively easy to maintain, and easy to customize. They can also be comparable in aesthetics to more expensive pool decking materials.
While concrete has a reputation for being strong and durable, it’s also prone to cracking. By that, we mean it’s almost inevitable that your concrete pool deck will crack at some point in time.
As fiberglass pool manufacturers with years of installation experience, we can confirm that cracking concrete is a common issue in pool decks. Because it’s such a widespread problem for everyone who has concrete on their property (we’re guessing 99.9% of all homeowners), we’re going to explain how concrete cracks, why it cracks, and what you can do to repair it.
Why does concrete crack?
Concrete usually cracks for at least one of the following reasons:
- Structural settling
- Ground movement
- Poorly placed control or expansion joints
- Improperly mixed concrete
- Fluctuations in temperature
Cracks in a concrete deck can be the first sign of structural settling or ground movement. If the cracks are still active, you need to hire an engineer to find out the cause and get to the root of the problem before you try to patch the cracks in your pool deck. This is especially important for cracks close to the pool because it can mean bigger and more expensive problems for your swimming pool in the future if you don’t act fast.
Poorly placed control or expansion joints can also cause your concrete pool deck to crack. Concrete has a tendency to crack every 10-12 feet, so we create intentional breaks to allow the cracks to form there. If the breaks are spaced too far apart, new cracks will appear.
If your concrete was mixed with too much water, this could lead to excessive shrinking during the curing process and, you guessed it, cracks in the deck.
Does concrete crack under heat?
Yes, concrete expands and contracts when heating and cooling, also referred to as thermal expansion. If expansion joints aren’t spaced properly, there’s a chance your pool deck can form cracks as the temperature changes. In addition, hot weather can crack concrete as it cools down if the surface of the concrete is different from the concrete’s interior temperature.
Why does concrete crack in cold weather?
Your concrete pool deck can crack in cold weather due to freezing and thawing cycles, which have similar effects as expansion and contraction in hot weather. When water molecules within the concrete freeze, they can over-expand, causing the concrete to break or crack.
How to Repair Concrete Pool Deck Cracks
Now that you know why your concrete pool deck can crack, you probably want to know how to fix it.
Cracked concrete repair usually means filling the crack with an appropriate material, like epoxy or grout. Let’s break down some of the most popular options.
Concrete Crack Filling
There are several ways to fill a concrete deck crack, including:
- Concrete patch mix
- Polymer-based filler
- Grout or cement
Concrete Patch Mix
The material that you use to fill the concrete crack will depend on the characteristics of the crack. Your first impulse might be to use a concrete patch mix, but these are best applied to cracks wider than ¼ inch. The good thing about a concrete patch is that you can use it to match the texture of the surrounding concrete, but the color will more than likely be off.
Epoxy fillers are resin-based and work well for cracks that are up to ¼ inch wide. It is not recommended to try to fill wide, structural, or active cracks with an epoxy filler.
Polymer fillers are also resin-based and can be used for smaller or narrower concrete deck cracks. Polymer fillers are comparable to epoxy fillers, but epoxy fillers are a little stronger, and they take longer to cure.
Unlike most of the caulk-like concrete crack repair products, vinyl concrete crack filler works great for small hairline cracks and wider cracks. You can buy a dry mix or pre-mixed product and apply it over the crack with a trowel.
Wider cracks in concrete can also be repaired using portland cement grout. This won’t form a structural bond with the concrete, but it can fill in the gaps and improve the appearance of your pool deck.
A dry mortar can be packed into the concrete deck crack as an alternative solution. This method is both durable and less prone to shrinkage, but it’s not suitable for shallow cracks.
Pro tip: deep, narrow cracks or cracks wider than ¼ inch may need to be stuffed with foam backer rod before the crack filler is applied.
Mending Bigger Concrete Cracks
Sometimes, applying a filler isn’t enough to fix concrete cracks. Your contractor may decide to staple or “stitch” the crack closed if the damage is more extensive. This can also help to prevent the crack from opening up again.
We recommend hiring a professional if you’re unsure about which method you will need to use to repair the cracks in your concrete. Of course, if you feel comfortable enough repairing it yourself, you can DIY the job.
Note: Unfortunately, cracks aren’t the only issues that appear in concrete pool decks, but they are the most common. Check out our article below on pool deck and patio materials to explore your other options:
Concrete Deck Repair Problems
If you splurged and went all out on multi-colored stamped concrete, you might be more than a little disappointed to see cracks forming on your beautiful poolside deck. We can take measures to prevent concrete cracks, but there’s no way to guarantee that cracks won’t appear.
Repairing concrete deck cracks is often simple, but there are a few problems that you can expect to encounter:
Matching the texture and pattern to the surrounding concrete is doable, depending on the material that you use to patch the crack, but it won’t always be an exact match. Your pool deck crack might still be visible even after repair, but it will be a visible filled crack instead of a mini canyon.
Unfortunately, matching the new concrete patch color is even harder than matching the texture to the surrounding concrete. Unless you paint your concrete deck with a suitable outdoor paint, the repair will remain visible.
And you know what, that’s okay. Take a deep breath and remember that everyone’s concrete cracks.
Have other questions or concerns about concrete pool decks? Ask away in the comments, and we will get back to you as soon as possible.
At River Pools, we’re fans of concrete around inground swimming pools thanks to its low cost and attractive look. However, we think that it’s up to you to choose the decking material that best reflects your tastes and suits your budget.
If you would like to reach out to us for pricing on a fiberglass swimming pool, click the button below and we will get in touch with you soon.