Are Sinking Pavers Around an Inground Pool a Danger in Miami?

You're skimming leaves off the pool and you notice it. The pavers around the pool are sinking along one side, there's a dip by the steps that holds water after a storm, and the joints have opened up enough to fit a finger. One homeowner described the same thing on a pool forum: "The pavers around my pool are sloping and sinking down, also coming apart." Their next question was the one you're asking now, which is whether this is just ugly or something you need to deal with.

The good news is that in most cases sinking pavers are a problem with the deck that leaves the pool alone, and a paver deck is one of the easier surfaces to put right because the pavers come up and go back down. The less comfortable part is that pavers don't sink on their own. Something underneath moved, usually water, and that's worth understanding before anyone resets a single stone.

The short answer, and what it depends on

Are sinking pavers around inground pool a danger?

Usually not to the pool itself, but they are a trip and slip hazard on a wet deck, and they tell you water is washing out the sand and base underneath. Most cases come down to a base that wasn't compacted well, joints that lost their sand, or water running under the deck. If the dip keeps growing, opens a hole, or sits next to a pool that's losing water, have it looked at soon.

The trip hazard is the part people underrate. A paver that's dropped half an inch is easy to catch with a bare toe, and around a pool everyone's barefoot, often wet, and sometimes running. Kids and older relatives are the ones who find the low spot first. A dip that holds water also stays slick and grows algae in the shade, which is its own slipping problem by the end of a Miami summer.

The pool shell is a separate structure from the deck around it, so a few sunken pavers rarely mean the pool is moving. Where it gets more serious is right at the coping. If the pavers that butt up against the coping have dropped away from it, rainwater and splash-out run straight down that gap and under the deck, which keeps the washout going.

Why pavers sink next to a pool

Pavers sit on a layer of bedding sand, which sits on a compacted base, and the whole thing is held in at the edges. When any one of those layers moves, the pavers follow it down. Around a pool, there are three usual causes.

The base wasn't compacted enough when it went in. This is the most common answer you'll hear from people in the trade, and it's often blunt. One reply to a homeowner with sinking pool pavers was that it was "a big mistake for them to install the finished surface without compacting first." Ground dug out for a pool and then backfilled is especially prone to settling if it wasn't compacted in layers, so a deck can look perfect for a year or two and then start dropping along one side.

Water is washing the sand out. "Water will wash out under your concrete and pavers, causing them to sink," as one reply put it to a homeowner three years into a new pool. In Miami that water comes from the June to October afternoon storms, from a downspout or a screen enclosure gutter that dumps onto the deck, and from splash-out at the shallow end. Once the joint sand is gone, every storm carries a little more of the bedding sand with it.

The pool is leaking. This one sounds alarming, but it's worth ruling out because it changes the fix. Someone replying to the same homeowner said it plainly: "Either they messed up the base layer, and or your pool is leaking." A slow leak from a fitting or a plumbing line under the deck keeps the ground wet in one area, and that's where the pavers drop.

Checks you can do this weekend

You can learn a lot before anyone comes out, and most of it costs nothing.

Do a bucket test on the pool. Set a bucket of pool water on the first step, mark the water level inside the bucket and on the pool wall, and leave the pump running as usual for a day or two with no rain. If the pool drops noticeably more than the bucket, you're losing water to more than evaporation, and that's a call for a pool leak specialist before the deck gets touched.

Walk the deck after a storm. Look for where the water goes. If it runs off the roof, the screen enclosure or the patio and pools in the low spot, you've found the source, and fixing the drainage matters as much as fixing the pavers.

Look at the joints. If you can see big gaps between the pavers and the sand is low or gone, the joints have been letting water straight down into the bedding layer.

Check the edges. Pavers that are "coming apart" at the outer row usually means the edge restraint has failed or was never there, and the field of pavers is slowly spreading outward.

Probe the low spot. Push a long screwdriver into the joints in the dip. If it slides in easily and goes deep, there's a void under there. A hole that keeps opening up, or ground that feels hollow, is a "stop and get it looked at" sign, because someone in a similar thread said it "sounds and looks like a sink hole. There is a lot of water moving around there somewhere." Most of the time it turns out to be washout from a leak or a downspout, but a growing void isn't something to guess at.

How it usually gets fixed

The question homeowners ask next is usually some version of "What's the least invasive way to fix these pavers??" The answer is that paver decks are forgiving. In the affected area, the crew lifts the pavers, digs out the washed-out sand, fixes or compacts the base, re-screeds the bedding sand, and sets the same pavers back down level with their neighbors. Then the joints get fresh sand, often polymeric, so they hold up better in the rain.

If it's a few blocks and everything else is solid, it's small work. One homeowner's advice on a thread about a small dip was to "pull the blocks up and fill in what you need to with sand, to a level that allows you to place the pavers back in flush." That's a reasonable DIY job for two or three pavers well away from the pool. Next to the coping, or across a large area, it's worth having someone do it, because the base has to be compacted properly and the slope has to carry water away from the pool, and a few degrees the wrong way puts the water right back under the deck.

Where the cause is a leak or a downspout, the fix comes first. Resetting pavers over a leak just means doing it again next year. A good crew will ask about the pool and the drainage before they quote, and the pavers page covers what that kind of job looks like in Miami-Dade.

If your deck is cool deck or poured concrete rather than pavers, and that's what's cracking and sinking, the pool deck resurfacing page is the better place to start.

What to ask before anyone resets them

A short list keeps the conversation on what is happening under the pavers:

• What do you think made these sink, and how will you check?
• Will you fix the base underneath, or only add sand and reset the pavers?
• How will you handle the joint at the coping so water doesn't run under it again?
• Which way will the finished deck slope, and where does the water go?
• What happens with the edge restraint on the outer row?

Get the answers and the scope in writing. Whoever does the work, the base and the water are what decide whether you're looking at the same dip next summer.

Getting it looked at

If it's a couple of pavers that dropped a little and the pool isn't losing water, it can wait for the dry season, roughly November to April, when the ground is easier to work. Mark the low spot so nobody trips on it. If the dip is growing, there's a hole, or the bucket test says the pool is leaking, don't wait for the next round of storms.

Call (786) 686-1048 and we'll connect you with a concrete contractor serving your part of Miami-Dade, someone who works on pavers around pools and can tell you what's moving under yours. Phones are answered 8am to 8pm, seven days a week. If you'd rather start online, you can request an estimate instead.

More on pavers in Miami.