How to Fix a Gap in Laminate Flooring

Gaps in laminate floors come from shifting planks, seasonal expansion, or installation errors. Three proven methods to close them — and which one to use for your specific gap.

By Chris Mendenhall

5 min read

A gap in laminate flooring shows up out of nowhere — one day your floor was tight, the next there’s a visible line between two planks. Sometimes it’s seasonal expansion. Sometimes it’s the planks having shifted. Sometimes it’s an installation defect that finally showed itself. The fix depends on the cause and the size of the gap, and most fixes are 15-minute jobs that don’t require removing planks. This guide walks through how to fix a gap in laminate flooring with three methods, so you can pick the right one for your situation.

What You’ll Need

  • A rubber mallet or hammer + a tapping block (a scrap of wood or laminate)
  • A pull bar (about $10 — designed for floating floors)
  • Wood filler matched to your floor color (for small permanent gaps)
  • A putty knife
  • Laminate seam filler (sold for this exact purpose)
  • A clean rag
  • A vacuum

Step 1: Identify Why the Gap Appeared

Different causes need different fixes.

Seasonal expansion gap

Floor planks contract slightly in dry winter air. If the gap appeared in winter and tightens up in summer, it’s seasonal — leave it alone or use a temporary filler. A humidifier in winter helps.

Planks shifted out of click-lock

The locking mechanism between planks can disengage if the floor was installed without proper expansion gap around the edges, or if heavy furniture was dragged across it. The planks need to be tapped back together.

Subfloor issue

If the gap appeared along with a high spot or low spot in the floor, the subfloor is uneven and the planks are flexing. Needs more than a quick fix.

Installation defect

The floor was installed too tightly to walls (no expansion gap) and is now buckling, creating gaps elsewhere. Needs the perimeter cut back.

Identify yours. Most gaps are #2 (shifted planks) — and that’s the easiest fix.

Method 1: Tap the Planks Back Together (For Shifted Planks)

This is the right method for the most common cause: planks that have separated at their joint.

Steps:

  1. Identify the gap and which planks shifted.
  2. Look at the end of the row — the gap usually traces back to a plank that needs to be slid back toward the wall on one end.
  3. From the wall side, use a pull bar hooked over the edge of the last plank, and tap the pull bar with a hammer. Each tap pushes the plank back into alignment with the rest of the row.
  4. If the gap is in the middle of a row, you may need to work from both ends — push one plank one direction while pulling another the other.
  5. Watch the gap close as you tap. Stop tapping the moment it’s flush.

Important: if you can’t access the end of the row without removing baseboards, take off the baseboards or quarter-round first. Trying to pull a plank without access to its edge will break the locking tab.

Method 2: Use Laminate Seam Filler (For Cosmetic Gaps)

If the gap is small and stable — not getting worse — but you can’t or don’t want to tap planks back together, a color-matched filler closes the gap cosmetically.

Steps:

  1. Vacuum the gap thoroughly.
  2. Match your filler to the floor color. Several brands make laminate-specific seam fillers (UniRepair, Konecto, color-matched putty sticks).
  3. Press filler into the gap with your finger or a putty knife.
  4. Wipe excess immediately with a damp rag.
  5. Let cure per package instructions.

This is a cosmetic fix only — it doesn’t lock the planks together. But for a small stable gap, it makes it invisible.

Method 3: Reinstall (For Severe Cases)

If multiple planks have shifted or the floor is buckling along an edge:

  1. Remove the baseboard or quarter-round along the affected wall.
  2. Check the expansion gap between the laminate and the wall — it should be 1/4 to 1/2 inch on all sides to allow seasonal movement.
  3. If the gap is too tight, use a circular saw or oscillating tool to trim the edge of the laminate back from the wall.
  4. Once expansion gaps are correct, lift the affected planks (they pop up by lifting at an angle — start from the end of a row) and re-engage them properly.
  5. Reinstall the baseboards.

This is more involved but addresses the root cause if the floor is fundamentally too tight.

Special Case: Laminate vs. LVP (Luxury Vinyl Plank)

Most of this guide applies equally to laminate and LVP, but LVP is more forgiving of shifting because the planks are slightly flexible. For LVP gaps, the tap-back method works even better.

For real hardwood that looks similar to laminate, this guide doesn’t apply — hardwood nailed to a subfloor doesn’t shift the same way.

Common Mistakes to Avoid

Tapping with a regular hammer directly on the plank. Always use a tapping block (a piece of scrap laminate or wood between the hammer and the plank) or a pull bar — never the hammer directly on the floor. You’ll damage the plank’s edge.

Filling a gap that needs the planks tapped together. Filler in a separated joint will pop out as the plank continues to shift. Address the cause, not the symptom.

Ignoring the expansion gap. If your laminate floor has no expansion gap at the walls, it will buckle as it expands. The gap is built into the design.

Working with too-soft filler. Some fillers shrink as they cure and the gap reappears. Use a filler designed for laminate seams, not generic wood filler.

Pulling on the visible side of a plank. Always pull from the end, not the long side. Pulling from the side will rip the click-lock joint.

Frequently Asked Questions

Should I run a humidifier in winter to prevent seasonal gaps? Yes, especially in homes with low winter humidity. Keep relative humidity at 35–55% year-round and laminate moves less.

My floor is gapping near a heating vent. Why? Heat from the vent dries the laminate locally, causing it to contract. Either redirect the airflow with a vent deflector or accept the gap as seasonal.

Can I just replace one plank in the middle of the room? For floating floors, yes — but you have to remove every plank between the wall and the damaged one. Cutting out a single plank is hard but possible with specialty tools and a steady hand.

The gap is too big to tap shut. That means the floor has expanded too much somewhere else (the wall sides need more expansion gap), OR a plank’s click-lock is broken. Address the cause, or that plank may need replacement.

Will fillers turn yellow over time? Quality laminate seam fillers don’t. Generic wood fillers can yellow. Buy the right product.

A Tight, Quiet Floor

Laminate gaps look alarming but are almost always fixable in 15 minutes with simple tools. The trick is identifying whether you have a shifted plank (tap-back), a stable cosmetic gap (filler), or a real installation issue (reinstall). Match the fix to the cause and your floor goes back to looking — and feeling — solid underfoot.