Pool Deck Crack Filler: Smooth, Safe Deck Repairs
Pool decks see more water than any other slab you own: splashes, wet feet, hoses, rain and sometimes salt or chlorinated water every day of the season. So when cracks show up, water goes straight into them and under the deck. A pool deck crack filler keeps that water out and gives bare feet a smooth surface, as long as you treat cracks, joints and coping differently.
For narrow, stable cracks in a concrete pool deck, a no mix concrete crack filler goes in neatly from the bottle and cures weather-resistant. The joint between the deck and the pool coping needs a flexible sealant, and anything involving the pool shell needs a pool professional.
The Short Answer
Fill narrow, stable cracks in a concrete pool deck with a ready-to-use filler after cleaning and drying them, leaving the repair flush and smooth for bare feet. Seal the joint between the deck and the coping with a flexible joint sealant, not a hard filler. Cracks in the pool shell or coping, sinking deck sections, or cracks near equipment and plumbing should be checked by a pool professional.
Why Pool Decks Crack
- Constant moisture soaking the soil underneath and causing settling
- Freeze-thaw in colder climates, especially if the deck isn't drained or covered in winter
- Shrinkage in the slab as it cured
- Heat expansion in hot sun, with a lot of movement at the coping joint
- Leaks from pool plumbing washing out the base
If cracks keep appearing in one area along with water loss from the pool, a hidden leak may be washing out the base. That's a reason to call a pool professional.
Cracks, Joints and Coping
Cracks in the deck
Irregular lines across the slab. Narrow and stable ones are a DIY fill.
The coping joint
The gap between the deck and the coping (the edge stones or concrete lip around the pool) is a joint that must flex as the deck and pool move separately. It should be sealed with a flexible joint sealant. Hard filler here can crack or even push on the coping.
The coping and pool shell
Cracked coping stones, loose coping or cracks in the pool wall itself are pool-structure repairs. Leave those to a pool contractor.
Choosing a Pool Deck Crack Filler
- Weather resistance once cured, for sun, water and seasons
- Smooth, flush finish so it doesn't scrape bare feet
- Clean application to avoid stains on a decorative or coated deck
- Compatibility with coatings, if your deck has a textured or cool-deck finish; check the coating maker's repair guidance
The Crack Repair Filler by VALYA is ready to use, water-activated, and suitable for concrete, stone, masonry and brick. For more on how these fillers work, see our guide to powder concrete crack filler. It's also our pick as the best concrete crack filler for walkways leading to the pool.
How to Fill a Pool Deck Crack
Do this when the pool area will be dry for a while, ideally outside of swim season or on a dry stretch.
- Clean the crack of dirt, algae and loose bits with a thin screwdriver and stiff brush.
- Rinse off chlorine or salt residue, then let the crack dry completely. A damp crack won't bond well.
- Blow or vacuum out the dust.
- Fill the crack with the pointed applicator.
- Level it smooth with a putty knife, feathering the edges so there's no ridge.
- Mist lightly with water and let it set.
- Keep foot traffic and splashing off until it's fully cured, following the product directions.
Sealing the coping joint
- Remove old, failed sealant from the joint.
- Clean and dry the joint.
- Insert backer rod if the joint is deep.
- Apply a flexible joint sealant rated for pool decks and tool it smooth.
Mistakes on Pool Decks
- Filling the coping joint with hard filler
- Working on a wet deck
- Leaving a rough ridge that scrapes feet
- Ignoring a possible pool leak behind repeated cracking
- Letting swimmers splash on uncured repairs
FAQ
How do I fix cracks in my concrete pool deck?
Clean and dry the crack, fill it with a concrete crack filler, smooth it flush, and keep water off until it cures.
What goes in the joint between the pool deck and coping?
A flexible joint sealant, often over backer rod. That joint has to move as the deck and pool expand and contract.
Can I fill cracks in my pool's coping?
Cracked or loose coping is usually a job for a pool contractor, since it's part of the pool structure.
Why does my pool deck keep cracking?
Often settling from water under the deck. Repeated cracks with water loss from the pool can point to a leak.
Wrapping Up
A pool deck crack filler keeps water out and the surface smooth: clean, dry, fill flush and let it cure. Use flexible sealant for the coping joint, and call a pool professional for coping, shell or leak problems.
If your pool deck has narrow, stable cracks, take a look at the Crack Repair Filler by VALYA and see if it fits your project.