Why Your Pool and Deck Should Be Renovated Together

Chris Oswalt

President of Probuilt Renovations

September 23, 20267 min read

See how we renovate pool decks and patios

A newly finished inground pool and a matching poured concrete deck in a Kansas City backyard, both renovated as one project.

If you have ever wondered whether your pool and your deck should be two separate projects or one, the short answer is one. Renovate them together. A new pool ringed by a tired deck looks like a new pool ringed by a tired deck, and that is the smallest reason to do it. The bigger reasons are that doing both at once is cheaper and less work than doing them apart. Three things drive that: the expansion joint between your coping and your slab, the cost of opening the same ground twice, and the plumbing buried under your feet.

Looks are the smallest part of the argument, and if that were the whole case I would not bother writing this. Let me go through the other three, because each one of them costs real money when the projects get split up.

Below I will walk through what the joint between your pool and your deck actually does, why splitting the work means paying for the same setup twice, and what is sitting in the ground under the slab you are about to pour.

The Technical Part: The Expansion Joint

A gap sits between your pool coping and your deck, and it is supposed to be there. It is called an expansion joint, and it is packed with foam backer rod and a flexible sealant. The reason it exists is that the environment moves the coping and the deck differently.

Your pool shell is set in compacted soil and it basically stays put. Your deck sits on a gravel base over whatever dirt was already in your yard, and it moves constantly. Something has to give between the two, and the joint is what gives.

When the sealant in that joint dries out and fails, water gets into the gap and down into the soil under the slab. Kansas City winters take it from there. Water freezes, expands, thaws, refreezes, and the gap gets a little wider every round. That sealant has maybe five to ten years in it before it needs redoing, and when we go inspect a failed pool deck, that joint is usually where the trouble started.

Close-up of the expansion joint between pool coping and a concrete pool deck, with the flexible sealant cracked and pulling away from the edge. — This is what a joint at the end of its life looks like: the sealant split and shrunk back, dirt packed into the gap, and hairline cracking starting in the slab beside it.

So here is the argument. Renovate both at once and that joint gets cut, packed, and sealed as one piece of work, with new material on either side of it. Renovate the deck five years after the pool and you are pouring fresh concrete against coping that already has five more winters on it. Our pool deck and patio renovation work almost always goes better when the shell and the slab are handled as one system rather than two appointments.

The Money Part: Paying to Open the Same Ground Twice

Every renovation carries costs that have nothing to do with materials. Crews mobilize. Equipment comes in. The same stretch of ground gets opened, worked, and closed. Your backyard is a job site instead of a backyard.

Split the projects and you pay for all of that twice. The setup, the hassle, the disrupted peace, and the transportation of equipment all find their way into your bank account one extra time.

There is also a timing piece, and it is the reason we are publishing this in the fall. Around here, this work wants to happen before the ground freezes, and the sealed joint we just spent three paragraphs on is what carries your deck through winter. Wait until spring and you are calling everybody at once, in the same week as every other homeowner who looked at their deck in March and did not like what they saw. Book it now and you are swimming when it gets warm instead of watching a crew work.

If your deck is already cracking at the edge, one more winter is not a neutral decision. That gap gets bigger every freeze.

The Plumbing Part: What Is Sitting Under the Slab

We had a customer refinish her pool one year. She loved it. She came back the next year and tore the entire deck out.

Both jobs turned out great. But when that deck came up, her plumbing was sitting right there, so we replaced it while the trench was open. She got the backyard she wanted. It just took two seasons, two tear-ups, and two rounds of paying for it.

An open trench beside a pool where the concrete deck has been removed, exposing the buried return and skimmer plumbing lines before a new deck is poured. — With the deck out, the return line, the skimmer lines, and the main run to the equipment pad are all exposed and easy to work on. After the new slab is poured, reaching any of it means cutting concrete.

Here is what is actually down there. Your return line usually makes a full circle around the pool, under the deck. The main run out to the equipment pad sits in a trench eighteen inches down or deeper. Skimmer lines are in there too. With the deck out, all of it is exposed and it is ours to work with.

After the new deck is poured, none of it is. Getting to a leaking pipe under a slab means cutting concrete, digging, fixing, backfilling, and patching. You are not just paying for the repair, you are paying to undo and redo the deck you just bought. If you are already seeing water loss you cannot explain, read what a cracked or leaking pool actually takes to fix before you pour anything on top of it.

The pipe does not care that you just spent money on the deck. If it is thirty years old, it is thirty years old.

Key Takeaways

The short version

The gap between your coping and your deck is an expansion joint, and it is the most common failure point on a pool deck. Do both at once and it gets built and sealed as one system.
That sealant needs redoing every five to ten years no matter when you renovate.
Splitting the projects means paying twice to open the same ground, and losing your backyard to a job site twice.
Your return and skimmer lines run under the deck. While it is out, replacing them is simple. After it is poured, it means cutting concrete.
Fall is the right time to book. Spring is when everybody calls at once.

Frequently Asked Questions

Common questions answered

How do I know if the expansion joint around my pool has failed?

Go look at it. A gap that is noticeably wider than it used to be, sealant that is cracked or crumbled or straight up gone, coping that has shifted, waterline tile popping loose, or a deck edge sitting higher than the coping. Debris jammed into the gap counts too, because packed dirt locks the deck and the shell together and cancels out the whole point of the joint.

Can I maintain the expansion joint around my pool myself?

A lot of homeowners can. Rout the old sealant out, set new backer rod, and run a self-leveling sealant rated for chlorinated water. What is not a caulk job is a joint that keeps reopening, coping that is moving, or cracks running out into the deck. That is movement, and movement means something underneath needs looking at.

Can my pool deck be resurfaced instead of replaced?

Sometimes. If the slab is sound and the problem is surface level, an overlay works and costs less. If the slab has settled, heaved, or cracked through, an overlay is paint over a structural problem and it will show through. We would rather come look and tell you which one you have got.

How long should a pool deck last?

Poured concrete generally gives you a couple of decades, pavers and stone tend to go longer, and surface coatings are the shortest lived and need reapplying. All of that assumes it went in right and the joint around the pool stayed sealed. Your pool deck also takes more abuse than your driveway, since it is getting splashed with pool water and pool chemistry on top of the weather.

Do I have to renovate the pool and the deck at the same time?

No, and plenty of people do them separately for budget reasons. What it costs you is a second mobilization, a second season of your backyard being a job site, a fresh slab poured against older coping, and no access to the plumbing under the deck once it is closed back up. If the budget only reaches one this year, call us and we will tell you honestly which one is more urgent on your pool.

See how we renovate pool decks and patios