MAPIWhy Are Gaps Opening Between Laminate Floorboards?
An open laminate joint is usually a movement problem rather than missing material. The useful question is what allowed a board to shift away from its neighbor.
Pergo says fluctuations in humidity can cause laminate boards to shrink or expand slightly. That movement can loosen clicked joints and create openings between boards.
Key takeaways
- Pergo says humidity fluctuations can make laminate boards shrink or expand.
- Board movement can cause clicked joints to come loose and leave openings.
- The moved board should be identified before the joint is pushed back together.
- Repeated gaps suggest the underlying movement or installation condition still needs attention.
What it actually means
A laminate-floor gap is an opening at a joint where two previously connected boards have moved apart.
The main explanation
Pergo explains that changing humidity can alter board dimensions enough for a clicked joint to loosen and a board to move. This can leave a visible opening even when the plank itself is not broken.
Main causes and reasons
1. Humidity fluctuation
Laminate boards can shrink or expand as humidity changes.
How to recognize it
- Gaps vary by season
- Several joints change over time
- Indoor humidity has changed
Why it matters: Pergo identifies this movement as the reason some open joints form.
2. A board has shifted
Pergo advises identifying which board moved before closing the joint.
How to recognize it
- One joint opens while adjacent rows stay aligned
- Gap can be traced toward a wall
- Board appears displaced relative to neighbors
Why it matters: The gap is the result of board movement, so locating the direction of travel helps explain the opening.
How to identify your situation
Dimensional movement is likely contributing.
Next: Stabilize conditions and inspect whether the same board keeps shifting.
The clicked joint may have loosened as the board moved.
Next: Identify the direction of movement before attempting a model-approved correction.
Moisture damage may be present.
Next: Address moisture before treating the issue as a simple open joint.
What you can do
- Track whether gaps change with humidity.
- Identify which board moved and in which direction.
- Check nearby perimeter conditions for constraints or unusual movement.
- Avoid filling a moving joint with rigid material without manufacturer guidance.
- Use the flooring manufacturer's repair procedure for the exact product.
Common misconceptions
Pergo documents gaps caused by boards moving after humidity changes.
The movement pattern should be understood before choosing a repair.
When it may be a bigger problem
Get a flooring professional when gaps are widespread, boards are damaged, moisture is present, or the floor repeatedly separates after a correct repair.
Frequently asked questions
Can humidity create gaps in laminate flooring?
Yes. Pergo says humidity changes can make boards shrink or expand and open joints.
Why do laminate boards separate after installation?
Pergo explains that boards can move when humidity fluctuates, which can loosen clicked joints.
Should I fill laminate gaps with caulk?
Not as a default. The movement causing the joint to open should be identified first.
Why do laminate gaps keep returning?
Repeated gaps suggest the board is still moving or the environmental or installation condition has not been corrected.
Sources
- How can I fix open joints in my laminate flooring? — PergoOfficial
Written by Mapiance Editorial Team
The Mapiance Editorial Team researches, writes, reviews, and maintains practical guides and explainers for MAPIANCE.
Reviewed by Mapiance Editorial Team
Published Sep 20, 2026 · Updated Sep 26, 2026 · Verified Sep 17, 2026