Why Is My Laminate Floor Lifting?

Laminate flooring lifts at the joints or edges for one of a few common reasons: moisture getting into the core, no expansion gap left around the room's perimeter, or movement in the subfloor beneath it. Laminate is a floating floor, not fixed down, so it relies on being installed correctly to stay flat — when it lifts, it's almost always an installation or moisture issue rather than a faulty product.

Moisture is the most common cause

Laminate's core is typically a compressed wood-fibre board (MDF or HDF), which swells when it absorbs moisture. A spill left too long, a leaking appliance, or damp rising from the subfloor because a proper membrane wasn't used can all cause the boards to swell at the joints, pushing them up and apart. Once a laminate board has swollen from moisture, it generally won't flatten back out even once it dries — the damage to the fibre structure is usually permanent for that section.

Missing or insufficient expansion gap

Laminate needs a small gap (commonly around 8-12mm, though this varies by product — always check the manufacturer's spec) around the entire perimeter of the room, hidden under skirting board or beading, to allow the floor to expand and contract naturally with temperature and humidity changes through the year. If that gap is missing, too tight, or has been blocked by something (furniture pushed hard against the wall, a threshold strip fitted without a gap), the floor has nowhere to expand into and can buckle or lift instead.

Subfloor movement

If the subfloor itself isn't flat, or moves slightly (common with older suspended timber floors), the laminate above it can lift at weak points as it tries to sit on an uneven surface. This is less common than moisture or expansion-gap issues but worth ruling out, particularly in older properties.

Can you fix lifted laminate?

If it's caught early and the boards haven't actually swollen, sometimes the fix is simply re-establishing the expansion gap — trimming skirting, removing an obstruction, or re-cutting a threshold strip. If the boards have swollen from moisture, the damaged boards typically need replacing; with a click-lock laminate this can sometimes be done board-by-board without lifting the whole floor, depending on the layout and how far into the room the damaged area is.

Preventing it

Wipe up spills promptly, leave the correct expansion gap on every edge, and make sure any subfloor moisture issue is dealt with before laminate goes down — see our guide to subfloor preparation. It's also worth checking how long laminate needs to acclimatise in the room before fitting — skipping this step is a common cause of movement issues in the following weeks.

How to check if boards have actually swollen

Look closely at the joint where boards meet — if you can see a visible ridge, a slightly raised seam, or the surface texture looks disturbed right at the joint, the board has likely absorbed moisture and swollen. A board that's simply lifted from a missing expansion gap, without moisture involvement, usually still looks flat and undamaged along its length, just raised or bowed as a whole rather than damaged specifically at the joints.

Repairing vs replacing damaged sections

With a click-lock laminate floor, replacing individual damaged boards is often possible without lifting the entire floor, particularly if the damage is near a wall or the room's edge, though boards in the middle of a large expanse can be more involved to access. If several boards across a wide area have swollen, or the floor was glued rather than floated, a full or partial re-lay is often more practical than trying to replace boards piecemeal. Getting a professional opinion before deciding is worthwhile if you're unsure how far the damage extends, since moisture can travel further under the surface than is visible from above.

Should you claim on a manufacturer warranty?

If you believe the laminate itself is defective rather than an installation or moisture issue, most manufacturers require photographic evidence and sometimes a sample of the affected board, along with proof of purchase and installation date. Genuine manufacturing defects are relatively uncommon compared with installation-related lifting, so it's worth ruling out expansion gap and moisture causes first, since a warranty claim is likely to be declined if either of those is found to be the actual cause.

Keeping a note of when and where you fitted laminate, along with the product and batch details, is genuinely useful if a warranty question ever arises later, since manufacturers often ask for this information and it's far easier to find at the time of fitting than several years afterwards.

Related reading: wood flooring creaking.