Why Engineered Vinyl Click (LSPC) Swells & How to Fix It
- William
- Jul 14
- 8 min read
Updated: Aug 11
Key Takeaways
Root cause: Most swelling and buckling in Engineered Vinyl Click (LSPC) floors stems from installation errors, not product defects
Top triggers: Insufficient expansion gaps, excess subfloor moisture, uneven subfloors and trapped debris in lock joints
DIY scope: Minor edge swelling can be fixed at home; widespread buckling usually requires professional attention
Product difference: Gluedown Engineered Vinyl Plank (LVP) rarely suffers from full-plank swelling issues
Prevention rule: Proper subfloor prep, acclimation and correct gap sizing prevent the vast majority of swelling issues in Dutch homes
Engineered Vinyl Click (LSPC) is loved by Dutch homeowners for its fast DIY installation, built-in sound reduction and waterproof performance. But if you notice raised edges, buckled sections or a popping feeling underfoot, you are dealing with floor swelling — one of the most common issues with floating click floors.
In almost all cases, swelling is not a product failure. It is almost always caused by installation mistakes, poor subfloor preparation or unaddressed moisture in the subfloor — especially in older Dutch canal houses, terrace homes and damp basement conversions with high seasonal humidity.
This guide breaks down the most common causes of LSPC swelling, which issues you can fix yourself, when to call a professional, and how to prevent it from happening again long-term.
Swelling Causes & Fixes Quick Reference
Cause | How to Spot It | Can You DIY Fix It? |
Insufficient expansion gaps | Buckling near walls and door frames; popping sound when stepped on | Yes – trim edges and add proper gap |
Subfloor moisture | Widespread soft raised areas; worse in damp basement rooms | Partial – fix moisture source first; may require reinstall |
Uneven subfloor | Buckling in consistent low/high spots; flexing underfoot | No – requires full re-prep and reinstall |
Debris in lock joints | Small isolated buckles along seam lines | Yes – near walls only; clean and re-click |
Sudden temperature swings | Widespread mild buckling after heating season change | Often self-resolves; add expansion gap if needed |
Wrong underlayment | Soft, bouncy feel underfoot; widespread flexing | No – requires removal and correct underlay setup |
6 Most Common Causes of Engineered Vinyl Click (LSPC) Swelling & Buckling
As a floating floor system, Engineered Vinyl Click (LSPC) expands and contracts naturally with temperature and humidity. It needs room to move and a flat, dry base to stay flat. When either condition is missing, the floor swells or buckles.
1. Insufficient Expansion Gaps
This is the single most common cause of buckling in click vinyl floors.
Like all flooring materials, Engineered Vinyl Click (LSPC) expands and shrinks with changes in temperature and humidity. If installers leave too small a gap around walls, door frames, pipes and fixed furniture, the planks have nowhere to go when they expand. They push against each other and buckle upwards in the middle of the room.
This is especially common in Dutch homes with water-based underfloor heating, where temperature changes are larger and more frequent across seasons. Per official Braag installation specifications, an 8mm expansion gap is required for all fixed obstacles.
2. Excess Moisture & Subfloor Dampness
Moisture seeping up from below is the second leading cause — and a very common issue in older Dutch basements and ground-floor rooms.
While the vinyl plank itself is 100% waterproof, excess moisture can seep into click joints and saturate the integrated IXPE underlay over time. A damp underlay swells slightly and lifts the planks, creating unevenness and tension in the lock joints.
Standing water left on the floor for multiple days can also seep through seams and cause localised edge swelling.
3. Uneven or Unprepared Subfloor
A flat subfloor is non-negotiable for click flooring.
Engineered Vinyl Click (LSPC) requires a subfloor flat to within 2mm deviation over 2 metres. High spots and low spots cause planks to flex and shift. Over time, uneven support creates tension in the locking system and leads to localised buckling.
In older Dutch homes, shifting foundations and uneven concrete slabs make this an extremely common issue that is often overlooked during quick DIY installs.
4. Debris Trapped in Locking Joints
Even tiny particles can cause problems during installation.
If sand, dust, drywall grit or small debris gets caught inside the click joints during installation, it prevents planks from seating fully flat. The trapped debris creates a small raised point that turns into a larger buckle as the floor expands and contracts with seasonal changes.
Over time, the grit also wears down the locking tabs and weakens the joint permanently.
5. Sudden Temperature & Humidity Swings
Fast changes in environment put stress on the floor.
Turning underfloor heating straight up to full heat after winter, or opening all windows during a sudden warm spring spell, causes rapid expansion. If the floor was installed during a cold, dry season and then exposed to warm humid air, it can swell faster than the joints can accommodate.
Skipping the mandatory 48-hour acclimation step before installation makes this issue much more likely to occur.
6. Wrong or Missing Underlayment
Braag Engineered Vinyl Click (LSPC) comes with pre-attached IXPE underlay engineered specifically for the product. Adding extra underlay causes predictable problems.
A second underlay adds too much cushion and lets planks flex too far underfoot. Extra thick underlay also acts as an insulator and traps moisture, raising the risk of swelling from below. Some installers skip underlay entirely on hard concrete, which leads to hard contact and uneven support across the floor.
DIY Fixes for Minor Swelling
You can fix mild, localised swelling yourself if the issue is near the edge of the room and the locking joints are still fully intact.
Fix 1: Add or widen expansion gaps
If the floor is pushing tight against walls or door frames:
Carefully remove skirting boards or quarter-round trim.
Check if the plank edges are pressed hard against the wall.
Use a multi-tool to carefully trim the plank edges back to create an 8mm expansion gap all around.
Replace trim once complete. The tension will release and buckling will usually flatten out within a few days.
Fix 2: Clean debris from a single joint
If a small buckle runs along one seam near a wall:
Disassemble planks back to the affected joint.
Vacuum and wipe both sides of the lock joint completely clean.
Re-click the planks carefully, making sure they seat fully flat.
This only works near walls or doorways; joints in the middle of the room are too hard to reach without breaking lock tabs.
Fix 3: Reduce moisture and allow the floor to dry
If swelling appeared after a leak or period of high humidity:
Fix the source of moisture first.
Increase ventilation in the room and run a dehumidifier.
In many cases, the floor will settle back down as it dries out.
If it does not flatten within 1–2 weeks, the underlay may be permanently swollen and the affected planks will need replacing.
What not to do
Do not glue buckled planks down. This will make the problem worse and can damage the locking system permanently.
Do not place heavy weights on buckled areas to try to flatten them. This can crack the core or break lock tabs.
Do not ignore the problem. Tension in buckled floors will only get worse over time and will eventually break the joints.
When to Call a Professional
DIY only works for small, edge-located issues. Call a professional installer if:
Buckling is widespread across the middle of the room
You can feel soft or hollow spots across large areas
Locking joints are breaking or planks are separating
The subfloor is clearly uneven or has active moisture problems
The floor was installed without acclimation and is buckling everywhere
In most cases of widespread buckling, the only permanent fix is to pull up the floor, properly prepare the subfloor, fix moisture issues and reinstall with correct expansion gaps.
How to Prevent Engineered Vinyl Click (LSPC) Swelling Long-Term
Based on field service data, over 90% of swelling issues stem from avoidable installation errors. Follow these rules to keep your floor flat and stable:
Always acclimate planks for 48 hours before installation. Let the flooring reach room temperature and humidity in the actual room it will be installed in.
Leave an 8mm expansion gap around all walls, pipes, door frames and fixed furniture. Never fit planks tight against walls.
Prepare the subfloor properly. Make sure it is flat to within 2mm over 2 metres, fully dry and free of debris. Test concrete subfloors for moisture before installation, especially in ground-floor and basement spaces.
Use only the integrated IXPE underlay. Do not add extra underlayment on top of Braag Engineered Vinyl Click (LSPC) planks.
Ramp underfloor heating gradually. Never turn heating straight to full temperature. Increase by 2–3°C per day over 7 days.
Wipe up standing water promptly. While LSPC is waterproof, prolonged standing water can seep through joints over time, especially during wet autumn and winter seasons in the Netherlands.
Line-Specific Note
Swelling and buckling are almost exclusively issues with floating click floors. Engineered Vinyl Plank (LVP) installed with full-spread adhesive is far less prone to buckling, as the glue holds planks firmly in place and reduces natural movement.
If you are renovating a permanently damp basement or high-moisture ground-floor space, gluedown fooring is usually the more reliable long-term choice.
Frequently Asked Questions (FAQ)
Q: Why is my Engineered Vinyl Click (LSPC) floor swelling and buckling?
A: In almost all cases, swelling is caused by installation issues, not a product defect. The most common causes are insufficient expansion gaps, excess subfloor moisture, an uneven subfloor, debris trapped in lock joints and sudden temperature changes.
Q: Will swollen click vinyl flooring go back down on its own?
A: Sometimes. If swelling is caused by a temporary rise in humidity and there is enough expansion gap, the floor may flatten back down as conditions return to normal. If the floor is tight against walls or the underlay has absorbed water, it will not fix itself.
Q: Can you fix a buckled vinyl click floor without replacing it?
A: For small, edge-located buckles caused by tight expansion gaps, you can trim the plank edges to add more gap and release tension. Widespread buckling from an uneven subfloor or moisture damage usually requires full or partial reinstallation.
Q: Does water cause Engineered Vinyl Click (LSPC) to swell?
A: The vinyl plank itself is 100% waterproof and will not swell from water. However, prolonged standing water can seep through click joints and swell the integrated IXPE underlay underneath, which can lift the planks and cause buckling.
Q: How much expansion gap does Engineered Vinyl Click (LSPC) flooring need?
A: Braag Engineered Vinyl Click (LSPC) requires an 8mm expansion gap around all walls, pipes, door frames, columns and fixed furniture. This gives the floor room to expand and contract naturally with temperature and humidity changes.
Q: Is it normal for click vinyl floors to pop when you walk on them?
A: Occasional soft clicks are normal in the first few weeks as the floor settles. Loud popping or crunching sounds usually mean there is an underlying issue: insufficient expansion gap, uneven subfloor or debris in the joints. These issues will get worse over time if not fixed.
Final Verdict
Swelling and buckling in Engineered Vinyl Click (LSPC) floors is almost always preventable and usually fixable — as long as you catch it early and address the root cause.
For Dutch homeowners, the biggest risk factors are damp ground-floor and basement subfloors, older uneven foundations and seasonal humidity swings. With proper subfloor preparation, correct expansion gaps and gradual temperature control, your Engineered Vinyl Click (LSPC) floor will stay flat and stable for decades.
Get more guidance
👉 For more amazing events and product details, follow our Instagram https://www.instagram.com/p/Da_1l9Fiucu/?utm_source=ig_web_copy_link&igsh=MzRlODBiNWFlZA==👉 Contact our support team – get product-specific advice for your floor issue
