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Why Does My Laminate Floor Feel Spongy?


Laminate flooring is a popular and affordable alternative to hardwood for homeowners who want natural wood’s premium look and feel without the high cost.

Not only can laminate flooring have the same aesthetic appeal as hardwood, but it can also be easier to clean and maintain while being available in various colors to suit almost any taste or style of décor.

However, a common issue in laminate flooring is a spongy feeling to the floor or having what feels like soft spots in the floor that feel bouncy as you walk over them.

In this article, we’ll discuss some of the most common reasons why a laminate floor feels spongy and how you can go about fixing this issue.

There are six potential reasons why a laminate floor feels spongy. Reasons include damage to the laminate floor from water or termites, various installation issues including an uneven subfloor, insufficient expansion gap or underlay problems, and, finally, specific subfloor structural issues.

Read on to find out if the spongy feeling in your laminate floor is due to something minor that you can fix quickly and easily or whether you’re looking at a more intensive and potentially more costly fix.

Six Common Causes of Spongy Laminate Flooring

From a subfloor that’s uneven or has structural issues to water damage, here are six potential problems that could cause your laminate floor to feel spongy:

The Laminate Floor Is Water Damaged

While laminate flooring is renowned for its durability, one of the biggest culprits of laminate floor damage is water. Because of this, it’s one of the potential causes of a spongy floor that we recommend diagnosing or ruling out first.

It’s important to note that you can get both water-resistant and waterproof laminate floors, and here’s the difference:

Water-Resistant Laminate Floors

These usually feature an aluminum oxide ‘wear’ layer on top, which provides a good level of moisture resistance for minor spills, and this gives you a bit of time to clean it up before it soaks into the laminate board. Long-term exposure to moisture will damage a water-resistant laminate floor.

Waterproof Laminate Floors

As they’re fully waterproof, these laminate floors prevent water from being absorbed into the board no matter how long you leave it on the surface.

If your laminate floor is the water-resistant variety, extended exposure to moisture that ends up getting absorbed into the boards’ core can cause them to swell and warp.

Because of this, it’s essential to keep an eye out for leaks from radiators or leaking windows, for example, and to ensure you dry these up as a priority.

why does my laminate floor feel spongy article image - image showing water on a laminate floor

©mariakraynova/123RF.COM

Some laminate manufacturers even go as far as recommending that you don’t use a steam cleaner or mop on your floor, as regular exposure to moisture from either of these can cause issues.

For example:

Do not use steam cleaners or wet mops, which may cause irreparable damage to your floor.

Shaw Floors

It’s also worth mentioning that in most cases, manufacturers recommend additional sealing of laminate floors in commercial applications and for particularly wet household applications, such as laminate floors in entrance halls and laundry rooms.

We’ve written an article discussing the need for sealing laminate floors, but to summarise, sealing the edges of a laminate floor with a silicone sealant around the floor’s expansion gap and between the joints of the various boards is recommended for particularly wet applications.

When water damage occurs, the laminate boards will typically swell or warp, which can cause the floor to rise at specific points creating gaps or voids underneath. As you walk across these areas, the laminate will dip under your weight, ultimately springing back as you remove your weight to give the floor a springy or spongy feeling.

In most cases, you won’t be able to fix a water-damaged laminate floor, and so the only option is to replace the affected boards.

You should always address the causes of the moisture issue before replacing your laminate floor to prevent a repeat of the spongy or soft spot issue in the new floor.

We’d also recommend checking the subfloor, for example, the underlying floor joists and the subfloor covering, to ensure that the excess moisture issue has not damaged these.

Persistent moisture can lead to rot and deterioration of the subfloor structure, leading to structural problems, so it’s worth assessing the damage here and getting professional guidance if necessary.

Here are a few tell-tale signs that water damage could be the cause of your spongy laminate floor:

  • Localized Damage – Any damage is most visible close to potential water sources such as radiators or windows. The damage could include lifted floors caused by warping, delamination as the laminate’s layers come apart, and a spongy sensation or moist, squelching sound as you walk over the problem area.
  • Signs of Discoloration – Look out for staining or color changes, for example, dark spots on the floor, which could be mold or mildew growth from excessive moisture.
  • Odors Coming From the Floor – Get down to floor level and check for any unusual smells coming from the floor, as this could indicate that mold or mildew is present either on the laminate floor or in the subfloor.

The Laminate Is Laid on an Uneven Subfloor

Another possibility is that your laminate floor sits on top of an uneven subfloor.

You should always install laminate flooring on as flat and level a surface as possible, as failure to do so can cause gaps or voids underneath some parts of the floor.

While the floor might look flat to the eye, this could be due to the tongue and groove joints keeping certain boards elevated above any voids caused by the uneven subfloor.

As weight is applied, the floor will sink into the void, and it will spring back given the tension in the boards and because the joints in the boards pull it back into position, giving it a spongy feeling.

In terms of diagnosing this issue, it can be difficult to do so unless you installed the laminate floor from new, and you’re aware of any high or low spots on the subfloor that you didn’t level out ahead of the laminate floor’s installation.

It’s worth mentioning that some laminate underlay manufacturers claim that their underlay can help address the issue of an uneven subfloor. While this is true, it only works up to a certain point, and the underlay is unlikely to resolve any extreme unevenness.

Here are some signs that an uneven subfloor could be the cause of your spongy laminate floor:

  • Localized Damage – One sign that an uneven floor could be to blame is if the spongy area is isolated. In other words, the sponginess occurs in a particular spot on the floor which usually looks flat when no weight is applied but dips down when walked over.
    The damage could also be away from potential moisture sources, which could rule out water damage (not always the case, it could be a pipe under the subfloor that you can’t see, for example). There might also be no apparent signs of warping or delamination and no squelching or moist sounds as you walk across the floor, which again could rule out water damage.
  • No Signs of Discoloration – There are no signs of staining or color changes, for example, dark spots on the floor, indicating that mold or mildew growth is present from excessive moisture.
  • No Odors Coming From the Floor – You can further rule out water damage if you get down to floor level and can’t detect any unusual smells coming from the floor, such as a musty or earthy smell caused by the presence of mold or mildew.

There Are Issues With the Laminate Floor’s Expansion Gap

A laminate floor needs to be able to expand and contract with changes in temperature and humidity.

What makes this possible is the expansion gap that must be left around the edge of the laminate floor, and this ranges from 3/8″ to 1/2″ wide in most cases.

Without this gap, the floor would butt up directly against the wall leaving nowhere for any expansion in the laminate to go, likely causing damage and lifting at the boards’ joints when expansion does occur.

Here are a few signs that the floor’s expansion gap (or lack of) could be the cause of the spongy sensation:

  • The Sponginess or Lifting Migrates Across the Floor – One of the easiest ways to diagnose an expansion gap issue is to watch for signs that the floor is lifting as if something is pressing on the laminate from underneath.
    If you step on the crest (i.e., the high spots) where the floor has lifted, which causes the crest to travel across the floor to another laminate board, then the issue is likely due to the lack of a sufficient expansion gap. The problem will appear to move across the floor as you walk on it, almost like a wave.
  • The Expansion Gap Is Non-Existent or Too Small – You can remove a baseboard at the edge of the floor to check whether a sufficient expansion gap is present to let the floor adjust to changes in temperature and humidity. If the floor is butted up directly against the wall, there is nowhere for any expansion to go, leading to high spots and a possible spongy feeling when you walk over it.

There Are Issues With the Laminate’s Underlay

Aside from perhaps the expansion gap, the underlay is arguably the most critical part of a laminate floor.

In addition to making the laminate floor feel softer underfoot, underlay also helps minimize the effects of deviations in the subfloor, which could cause the laminate boards to fit or sit poorly.

why does my laminate floor feel spongy article image - image showing laminate floor foam underlay

©luboivanko/123RF.COM

Any of the following underlay issues could result in the floor feeling overly spongy:

  • Areas where the underlay has scrunched up, folded over on itself, or overlapped to cause excessive cushioning in certain parts of the floor.
  • Situations where new underlay has been laid directly over an old layer of underlay, resulting in more compression as you walk over the floor, causing a spongy feeling.
  • Situations where the wrong type of underlay is used, for example, a carpet underlay that is usually much thicker and compresses more than a laminate underlay.

Provided your laminate floor isn’t glued, and it’s possible to remove the baseboards, it shouldn’t be too difficult to remove one of the laminate boards at the edge of the floor. Doing so will help you access the underlay to get a better understanding of the issue.

Where the underlay is at fault, unfortunately, there isn’t much you can do other than lift and refit the entire laminate floor after properly installing the correct type of underlay.

Thankfully, it is possible and relatively straightforward to lift and relay a laminate floor (provided it isn’t glued), but it will likely be very time-consuming.

Here are a few things to look out for to diagnose a potential underlay issue with your laminate floor:

  • The Issue Occurs Across the Entire Floor – A spongy sensation across the entire floor could indicate that two layers of underlay are present, one on top of the other, or perhaps the wrong type of underlay has been used, for example, a carpet underlay instead of a laminate-specific layer.
  • The Issue Is Localized – Any localized sponginess could be a sign that the underlay has scrunched or doubled up in a specific area, causing an excessive amount of sponginess in that area.
  • No Signs of Discoloration – There are no signs of staining or color changes, for example, dark spots on the floor, indicating that mold or mildew growth is present from excessive moisture.
  • No Odors Coming From the Floor – You can also potentially rule out water damage if you get down to floor level and can’t detect any unusual smells coming from the floor, such as a musty or earthy smell caused by the presence of mold or mildew.

The Laminate Floor Is Termite Damaged

Another potential cause of a spongy laminate floor is termite damage.

Thankfully, termite damage is probably one of the least common causes on this list, but unfortunately, it can be one of the most problematic.

You see, termites have a voracious appetite, and so even minor infestations can lead to extensive damage across both the laminate floor itself and the subfloor. Without any preventive measures to stop termites in their tracks, they can cause dangerous and potentially very costly structural issues.

Here are a few tell-tale signs that termite damage could be the cause of your spongy laminate floor:

  • Distinct Insect Damage – Termite damage can lead to sagging and blistering of the laminate floor, which can resemble water damage. It will also lead to distinctive insect damage, though, such as small holes in the laminate caused by the termites eating and tunneling their way through the surface layer.
  • Hollow Sounds – Listen out for hollow sounds coming from the laminate floor, caused by the termites hollowing out the inside of the laminate boards.
  • Odors Coming From the Floor – Termite infestations can produce an odor that smells like mold or mildew from water damage.

There Are Issues With the Subfloor

Finally, a laminate floor could also feel spongy as a result of structural issues in the subfloor.

Unfortunately, this is probably the most challenging issue to diagnose. It can often be difficult to diagnose or assess any problems without removing the laminate floor and perhaps even the subfloor covering.

Because of this, we recommend ruling out each of the above issues first, and we’d always recommend getting specialist advice when it comes to assessing any potential structural problems.

Here are a few causes of potential subfloor issues that could be causing the spongy sensation in your laminate floor:

  • Areas where the floor joists or the subfloor covering is damaged.
  • Where undersized floor joists have been used that are incapable of supporting the load placed upon them.
  • Where too few joists have been used, or they are spaced too far apart.
  • Where there is insufficient cross-bracing between the joists causing excess movement.

How Do You Fix Spongy Laminate Flooring?

Once you’ve identified the cause of your spongy laminate floor, the next step is to rectify the problem.

Here’s how to do it:

1. Address Any Moisture Issues (If Applicable)

As mentioned, one of the biggest culprits of laminate floor damage is water.

From discoloration to odors and mold or mildew growth, it’s usually pretty easy to spot the signs of water damage before even lifting the floor.

Go ahead and skip to the next option if this isn’t applicable; otherwise, here are some tips to help you address any moisture-related issues:

  1. Identify the source of the leak and ensure it has stopped.
  2. Remove excess moisture by using a wet vacuum to suck it up, opening windows to increase airflow, or by using a dehumidifier, for example.
  3. Complete repairs and any steps required to ensure the leak won’t reoccur.
  4. Assess the extent of the damage, remembering that mold growth can impact health and so needs dealing with as a priority.
  5. Pull up the damaged laminate boards.
  6. Check for subfloor damage at this point, especially if the leak was extensive and there are also signs of mold growth or damage to the subfloor. Get professional advice where needed.

2. Address Any Installation Issues (If Applicable)

From an even subfloor to expansion and underlay issues, there are plenty of installation errors that can lead to a spongy sensation in your laminate floor.

Where an uneven subfloor is to blame, potential fixes include:

  • Using a self-leveling floor screed where the subfloor is concrete.
  • Installing plywood underlayment to even out any gaps or inconsistencies.
  • Sanding the subfloor to level it out.
  • Injecting expanding foam under a soft spot to provide support and to prevent it from dipping under load.

For expansion gap issues, we’d recommend lifting and relaying the floor to provide the required gap to allow for expansion and contraction due to changes in temperature and humidity. Unfortunately, it will likely only be possible to relay the floor provided no glue was used during the original installation.

Finally, for underlay issues, you might be able to partially remove the floor to deal with an isolated case of folded underlay, for example. However, to rectify the entire floor, you’ll probably need to remove everything and replace the underlay correctly with the right type before reinstalling the floor.

3. Address Any Other Issues (If Applicable)

Finally, before replacing your laminate flooring, you’ll want to rectify other potentially serious issues such as termite damage or structural subfloor issues.

Depending on the extent of the issue, this could involve replacing the subfloor covering. More severe damage or subfloor inadequacies could require the replacement of joists or other structural components.

Like with water damage, these issues can lead to dangerous structural problems, and so we strongly recommend getting expert guidance for these issues.

4. Replace the Affected Boards (If Applicable)

Once you’ve addressed the above issues, the final step is to replace the affected parts of your laminate floor, which could range from a few isolated boards to the entire floor.

Always follow the manufacturer’s installation instructions, but a few things to look out for are that your subfloor is both structurally sound and even, you leave a sufficient expansion gap around the perimeter of the floor, and you seal the boards as per the manufacturer’s recommendations.

Following these steps should help prevent any spongy floor issues in the future.


Final Remarks

Laminate flooring is a popular choice for many homeowners because it’s affordable and easy to maintain.

There are some common causes of spongy laminate that you should be aware of, though, so you can troubleshoot the issue right away if your floor starts feeling spongy or soft in spots.

The six most likely culprits include water damage, uneven subflooring, issues with the underlayment, the lack of an expansion gap around the edges of the laminate floor, termite damage, and structural problems with the subfloor itself.

Depending on the extent of the problem, you might be able to replace individual boards, or it might require that you reinstall the entire floor after rectifying the original issue.

It’s essential to spend enough time diagnosing and dealing with the issue before relaying the floor; otherwise, you risk the problem of the spongy floor coming back with the newly laid laminate.

We’d always recommend getting specialist advice, especially when diagnosing and rectifying potential structural issues with your floor.


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Author: Jon Maxwell
Senior Writer, ToolCrowd
Jon Maxwell writes about various topics for ToolCrowd, including tool reviews, material advice, common home problems, and general DIY advice and how-to articles. His work has been published in national publications for audiences including consumers, homeowners, and industry experts. Jon has a bachelor's degree in Building Surveying and a master's degree in a branch of Civil Engineering focusing on concrete and steel durability. When he isn't writing for ToolCrowd, Jon enjoys completing DIY tasks in his own home, as well as woodworking in his home workshop, snowboarding, and website development. Contact Jonarrow_right_alt
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