Most pools have an expansion joint: a narrow gap between the coping stones in your swimming pool and the surrounding deck. In order to protect this joint, it’s common to place a flexible sealant (known as pool mastic) in the gap. The purpose of the pool mastic is to absorb the movement when the ground is shifting and temperatures are changing. It’s normal for the pool shell and deck to expand and contract at different rates, and the mastic helps to bridge these gaps.
Without pool mastic sealant, water can move into the joint and get into the base of the deck. As a result, it causes damage over time to the coping, tile, and the pool shell. So, maintaining the mastic seal is a critical step to preventing long-term damage to your pool and deck.
Here in the DFW area, we have clay soil that expands and contracts, as well as extreme temperature swings. These local conditions put higher levels of stress on the expansion joint compared to other areas, which means that the mastic is working harder and wears out faster here.
How Long Does Pool Mastic Last (And What Shortens Its Life in Texas)?
As a general rule of thumb, pool mastic generally lasts between 7 and 10 years in normal conditions. But here in Northern Texas, it’s more realistic to expect a mastic lifespan of around 5 to 7 years. Our clay soil shifts seasonally as moisture levels change, which is constantly putting stress on the expansion joint.
Other factors that speed up the degradation of pool mastic include UV exposure, contact with the pool chemicals, and the freeze-thaw cycles during the colder months. Over time, the sealant becomes less flexible, and eventually it hardens…which means that it can no longer do its job. We recommend that homeowners inspect the joint every spring, especially after a hard freeze occurs.
7 Signs Pool Mastic Needs Replacing
How do you know when to replace pool mastic? Here are a few essential signs that you might need pool mastic repair or replacement:
- There are visible gaps or cracks in the sealant, which are areas where the water can work its way under the decking.
- You can see a separation between the coping and the deck. If you can see a gap that is wider than a credit card, then it’s an indication that the mastic has lost its bond on one or both sides.
- The pool deck is starting to crack or lift, which could be a sign that water has been eroding the base.
- Pool tiles start falling off the wall. If the expansion joint fails, then the pressure that is normally absorbed by the pool mastic starts to affect the tile bonds.
- Near the pool edge, the deck is starting to heave. Soil movement that would have been handled by the pool mastic is now affecting the hardscape.
- Coping stones start to loosen because of water that seeps in under the coping. As a result, the mortar bed is dissolved over time, causing the stones to shift.
- The joint starts to have mold, mildew, or weed growth. If there are organic materials growing in the gap, then it means that the seal has failed.
DIY vs. Professional Pool Mastic Repair
When it’s time for pool mastic replacement, does it make sense to call a professional team, or is this something that can be done with a DIY project? If it’s a straightforward joint with clean and accessible edges, then DIY might be a possibility. You’ll need to remove all of the old material first, then install a backer rod and use the correct sealant type to get the best results. Keep in mind that if you use the wrong type of pool mastic, then it can result in premature failure and preventable issues.
Always call a professional pool repair team if you can see any of these signs:
- Coping stones are loose
- Tiles are falling
- The deck is heaving
All of these issues are an indication of structural problems that need to be repaired. Simply replacing the mastic won’t be sufficient.
More often than not, it makes sense to hire an expert team to ensure that the seal replacement is done right. Improper DIY removal or a mistake in the placement of the new mastic can result in a domino effect of issues that can be much more expensive to repair in the future.
Pool Mastic Replacement Cost in DFW, Texas
The amount that you will pay for a full pool mastic replacement depends on the size and type of pool that you have. The repair team also needs to look at the joint condition to determine final costs, especially if coping or deck repairs are necessary.
The longer you wait to replace a damaged mastic, the higher the likelihood that you will have a higher bill. When water starts to infiltrate the joint, it results in many different types of damage to the mortar bed, coping, and deck substrate. Too often, these issues are already occurring before the mastic failure is detected.
FAQs
What is the difference between pool mastic and regular caulk?
Pool mastic is a heavy-duty sealant that is very flexible and engineered for specific conditions such as the movement, chemical exposure, and UV conditions faced by the swimming pool expansion joint. In comparison, standard caulk doesn’t have the same elasticity and durability to hold up in these conditions.
How do I know if I need mastic replacement vs. a full pool remodel?
The best solution is to consult with a professional team to determine if a mastic replacement is sufficient or if a pool remodel is necessary. If the coping is still solid, then mastic replacement alone is often good enough. We’ll help you determine if deeper repairs are necessary.
Does pool mastic replacement require a permit in Texas?
In most areas, mastic replacement is considered routine maintenance, so it doesn’t require a permit. But if any additional structural repairs are needed for the coping or deck, then there might be permit requirements.
Expert Pool Installation and Quality Services
If you are thinking about pool installation in your yard, then contact our experienced team at Mid City Custom Pools. We offer personalized support to create the backyard oasis that you’ve always dreamed about. Contact Mid City Custom Pools to schedule a no-obligation consultation and learn more about available services.