Don’t Let Mold Ruin Your Vinyl Plank Flooring Dreams

Vinyl plank flooring is a dream come true: its waterproof, easy to install, and some are scratch resistant. Everything a homeowner is looking for. It’s important to install it properly to prevent moldy nightmares.

Although vinyl plank flooring is well-known to be waterproof, it does not mean that liquids can seep through the cracks, grooves, or edges and become trapped under the planks, allowing mold to grow underneath your floors. 

If not installed properly, mold can grow under vinyl flooring if moisture becomes trapped underneath the flooring material. Vinyl flooring is not a breathable material, which means that moisture cannot escape through the flooring. If there is moisture present on the subfloor, it can become trapped under the vinyl flooring, providing a favorable environment for mold to grow.

Vinyl flooring itself is not susceptible to mold growth since it is non-porous and does not provide a suitable food source for mold. However, mold can develop on the concrete subfloor if moisture or water vapor is present. If moisture seeps through the concrete or if there is poor ventilation, mold spores can find a conducive environment to grow.

Moisture can become trapped under vinyl flooring if the subfloor is not properly prepared or if there is a leak or flooding in the area. To prevent mold growth under vinyl flooring, it’s important to properly prepare the subfloor before installation and to ensure that there are no leaks or moisture issues in the area. This may involve installing a moisture barrier, ensuring proper ventilation, or repairing any leaks or water damage.

Although this is possible, it does not mean you cannot take the necessary precautions to ensure mold does not grow under the vinyl planks. 

How to Tell if Mold is Under Your Floor

If you suspect mold growing under the floors, then the best thing to do is check it out in these few simple yet effective ways. Remember that mold may not always be visible like we wish, but there are many ways you can tell if mildew is under your floors.

Be vigilant about where excess moisture in moist environments, such as laundry rooms, kitchen, or bathroom areas. Water damage can certainly cause the growth of mold and cause serious problems. Early detection is key to removing mold before it becomes a problem.

🔎 Watch out for a musty smell: The first step is to see if there is mold by your sense of smell. It will be very unpleasant and most likely resembles something similar to wet socks, a meaty scent, rotten wood, or anything that seems to be earthy-like. It may not be intense at times, but it should be noticeable enough to tell. One way to do this is by going by damp areas such as sinks or toilets, kneeling, and giving a quick sniff. 

🔎 Keep an eye out for visible signs: Usually, this contains a dark spot in one specific area, stains on the grout of vinyl or tile floors, velvet textures for wood surfaces, or distinctive coloring texture (dark green, black or brown, and sometimes yellow or orange.)

🔎 Watch out for any symptoms in your own body: Meaning that you may feel as if you have a sickness that won’t go away, your allergies are always acting out, any asthma you may have is getting worse, and there is no explanation, your body is itchy, or you may be constantly tired. If you experience these symptoms, you may have a mold infestation and a serious health hazard.

🔎 Check for any leaks in plumbing: Lastly, there may be a plumbing issue that you may not know. Watch the water bill to see if it mysteriously goes up, and check every pipeline that might leak somewhere, as this source may be feeding the mold and moisture under vinyl flooring.

Consider a Moisture Barrier

One of the main ways to prevent your vinyl plank flooring from growing mold is by considering a moisture barrier. Moisture barriers help reduce moisture and soundproof noisy luxury vinyl flooring.

Many contractors will tell you that vinyl flooring doesn’t need a moisture barrier. They claim it’s an extra step that isn’t needed. It is a common misconception that vinyl flooring doesn’t need a moisture barrier when installed over a concrete slab or wood subfloor.

A moisture barrier underlayment prevents moisture from the ground under the slab or inside a crawl space from collecting underneath your laminate flooring and causing mold to grow. We have seen it firsthand when vinyl flooring had moisture underneath it and had to be removed. Have your contractor conduct a moisture, calcium chloride, or RH test on your concrete, it is crucial to install a moisture barrier.

Can mold grow under a moisture barrier? A moisture barrier will certainly help prevent mold from growing under your flooring. It is still possible for mold to grow even with a moisture barrier if it is not sealed properly.

Make sure you seal everything properly during the floor installation to avoid any moisture reaching under the barrier.

How to Prevent Mold

It is important to inspect floors regularly or call a mold inspection specialist who can identify potential areas of concern.

Make sure your concrete subfloor is protected with an appropriate sealant or epoxy coating, and keep the wood subfloor or concrete subfloor dry by promptly addressing any general plumbing or water issues in the surrounding area. Properly sealing such areas will help you maintain an effective barrier between your floor and any moisture problems that could lead to mold growth.

🔎Look for Moisture Intrusion: If there are leaks or water issues in the area where the vinyl flooring is installed, moisture can penetrate the concrete slab. This moisture can create a damp environment that promotes mold growth.

⬇️Reduce High Humidity: In regions with high humidity, moisture from the air can accumulate on the concrete surface. If the moisture is not properly controlled or if there is inadequate ventilation, it can lead to mold growth. Make sure the humidity level in your home is under 60%.

💦 Be aware of Condensation: Concrete slabs can sometimes experience condensation, especially in areas with temperature fluctuations. Condensation occurs when warm air comes into contact with a cool surface, causing moisture to form. If the condensation is not effectively managed, mold growth can occur.

Is Mold Under Vinyl Flooring Dangerous?

Mold in your home is not only unpleasant, it’s also dangerous! Mold can cause many health problems, including allergic reactions, asthma attacks and lung damage! Therefore, it’s imperative to get rid of any (and all) traces of it from your home as soon as possible!

As mold spores spawn and grow, they release dangerous organic compounds into the air. These produce allergens, irritants and toxins which make it difficult to breathe and cause itchy, watery eyes, sneezing and coughing. If your home is ‘overrun’ by mold, then you’ll need to have it professionally removed.


In order to prevent mold from forming under your vinyl floor, you need to maintain it properly and keep it dry. Moisture caused by a large water leak, such as a broken pipe or a flood, can seep through the flooring and along the baseboards, resulting in mold. Even a small water leak from behind a sink or toilet can lead to mold growth over time.  If you suspect mold may be under your flooring, call the professional Bio Pro for a Mold Assessment.

Leave a Comment

Your email address will not be published. Required fields are marked *

Scroll to Top