Why Your Pool Deco Drains Pop Up in Winter (and How to Fix It)

Why Your Pool Deck Deco Drains Pop Up When It Gets Cold

We recently got a call from a homeowner — let’s call him Mike — who had just finished a DIY upgrade around his pool. He pulled out his old deco drains, cleaned the concrete channels, and snapped in brand new ones. They looked great… for a while.

Then the cold weather rolled in. Suddenly, the ends of those new drains started popping up out of the deck. Not only did it look bad, but it also created trip hazards right where people walk around the pool. Mike called us and asked, “What do you guys do to secure it down in the ground?”

If this sounds familiar, you’re not alone. Let’s walk through why this happens, what went wrong, and how to install deco drains so they stay put — even when the temperature swings.

What’s Going On: Why Deco Drains Lift in Cold Weather

In Mike’s case, he had one-piece plastic deco drain that was about 1 3/4 inches wide and roughly 4 inches tall, designed to snap into an existing concrete channel. On paper, he did the right things: pulled the old drain out, cleaned the dirt and debris, and pushed the new sections down into place.

So why did it start popping up once it got cold?

• Thermal movement: Plastic expands in the heat and contracts in the cold. Long, uninterrupted runs of drain can push and pull against the concrete, and if there’s nothing holding them down, the ends can work their way up.
• Loose fit in the channel: Over time, concrete channels can chip, widen, or get slightly out of square. If the new drain isn’t a snug fit, it can rock or lift when temperatures change.
• Trapped debris or high spots: Even a little leftover concrete, dirt, or a small stone under the drain can create a pressure point. As the plastic moves with temperature, it tends to rise at the weakest or highest spots — often the ends.

One key point from our call with Mike: he assumed the drain was meant to just “snap in” with no fasteners or adhesive at all. That’s true for some products, but not all — and not always in older or imperfect channels.

Different Types of Deco Drain Attach Differently

When Mike called, he said, “It’s deco drain, just like most people have.” The challenge for us is that there are actually several common styles:

• Two-piece, 3-inch drains: These usually have a removable top. Underneath, there’s a base that can be screwed into the concrete or set in mortar. The top then snaps back on. These are easier to clean and maintain.
• One-piece, snap-in drains: This is what Mike had — a single molded piece that’s pushed into a formed concrete channel. These rely more on friction fit, and sometimes a little adhesive, to stay in place.
• Narrow, low-profile channels: Some 3/4-inch or 2-inch decorative drains are used near coping or tight spaces. Many of these are meant to be set into fresh concrete or bedded in a thin layer of mortar or construction adhesive.

This is why we often ask customers to send us a photo. The way we secure a 3-inch, two-piece drain with screws is completely different from a 1 3/4-inch snap-in style. Getting the attachment method right is half the battle.

How to Install One-Piece Deco Drains So They Stay Put

If you’re working with a one-piece deco drain like Mike’s, here’s how we recommend installing it so it doesn’t pop up every winter.

1. Prep the Channel Thoroughly

Mike did a nice job cleaning out “dirt and junk,” but for long-term performance you want the channel as clean and smooth as possible.

• Remove all old drain pieces and any broken plastic.
• Use a small chisel, screwdriver, or oscillating tool to knock off any ridges of concrete.
• Vacuum out the channel to remove fine dust and grit.
• Check for high spots by setting a short piece of the new drain in place and seeing if it rocks.

Any bump underneath will become a lift point when the plastic expands and contracts.

2. Dry-Fit Everything Before You Commit

Before you reach for any adhesive, snap all the pieces together and lay them in dry:

• Make sure the sections aren’t too long for the channel. If necessary, trim them per the manufacturer’s instructions.
• Pay extra attention to the ends and around corners — these are the areas that usually pop first.
• Check that the top of the drain sits just slightly below or flush with the surrounding deck, not above it.

If they’re already tight and solid with no wobble, you may not need much extra help beyond a few strategic spots.

3. Use the Right Adhesive (and Not Too Much)

During Mike’s call, he told us he’d “never heard of anybody putting adhesive on this stuff.” We understand where that comes from — but in older decks or loose channels, a good adhesive can make the difference between drains that stay put and drains that become a seasonal headache.

Here’s how we typically approach it for one-piece plastic deco drains:

• Use a construction adhesive rated for plastic and concrete (often polyurethane-based). Avoid silicone caulk — it’s too flexible and doesn’t bond as strongly for this use.
• Apply small dabs or short beads every 12–24 inches, focusing on the ends and any spots that felt a little loose during dry-fit.
• Do not fully “bed” the entire drain in a continuous thick line of adhesive — that can trap water and make future replacement tougher.
• Press the drain firmly into place and wipe away any squeeze-out immediately, especially on the visible top edge.

The goal is to give the channel a few solid anchor points while still allowing the plastic to move a bit with temperature changes.

Seasonal Maintenance & Common DIY Mistakes

Once the drains are in, a little seasonal attention goes a long way toward keeping them flat and functioning properly.

Simple Seasonal Checks

• Fall: After leaves start dropping, check the drains for clogs. Debris-filled channels hold water, and repeated wet–freeze–thaw cycles put more stress on the plastic.
• Winter: After the first hard freeze, walk the deck and check for any new lifting at joints or ends. Catching a small lift early lets you re-seat or re-adhere a short section before it becomes a big problem.
• Spring: Hose out the channels to clear sand and fine grit. Grit can work its way under the drain and act like little jacks as plastic moves.

For two-piece drains with removable tops, pop the top off once or twice a year and fully clean the interior. Keeping the drain flowing reduces water pressure against the sides and the plastic itself.

DIY Mistakes We See All the Time

• Skipping the dry-fit: Cutting and gluing as you go can leave you with a last piece that’s under pressure and wants to pop out when the temperature changes.
• Not leaving any movement room: Pushing long runs tightly against a wall or column with no expansion gap encourages buckling or lifting at the weakest point.
• Using the wrong adhesive: Regular caulk or indoor-only adhesive won’t hold up to UV, water, and temperature swings on a pool deck.
• Ignoring a slightly lifted section: Once a corner or joint lifts, water and debris get underneath and make the problem worse. A quick fix early is much easier than a full replacement later.

Why Proper Drain Installation Protects Your Pool Deck

Deco drains do more than just look nice. When they’re installed correctly, they help:

• Move water away from the pool and house foundation.
• Reduce standing water that can lead to algae, staining, and slippery surfaces.
• Limit freeze–thaw damage at the deck edge by keeping runoff moving.

When they’re loose or popping up, you not only have a trip hazard, but also a path for water to get where it shouldn’t — under the deck, into voids, or against structures.

If your deco drains are starting to lift like Mike’s, we’re happy to take a look, help you identify the exact product you have, and either walk you through a solid DIY approach or handle the repair for you. A little attention now can keep your pool deck safer, better-looking, and in good shape through many more winters.