Does Humidity Affect Hardwood Floors? Protect Your Investment

Hardwood floors can be a great addition to any home. If you live in a humid area and are considering hardwood floors, you are bound to have some questions. Does humidity affect hardwood floors?

Humidity affects hardwood floors when the relative humidity is high. Hardwood floors absorb moisture from the air, causing the flooring to swell. When hardwood floors swell, the planks put pressure against neighboring planks causing buckling, warping, or cupping.

Does Humidity Affect Hardwood Floors? Protect Your Investment
Humidity can ruin a beautiful hardwood floor.

Hardwood floors are often expensive and require some work to maintain, but the benefits of having them in your home are worth it.

Having to deal with a high relative humidity level does have its drawbacks, but there are ways you can get around this obstacle and still enjoy a beautiful hardwood floor.

Hardwood floors are elegant, but high humidity can be very harsh on an ill-prepared hardwood floor.

Not only does high humidity cause damage to the structure of the hardwood flooring, but mold thrives in porous, moisture-filled environments.

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Does Humidity Affect Hardwood Floors?

In short, high humidity levels absolutely can affect your hardwood floors.

Yet there were ways to prevent damage to a hardwood floor by taking preventative measures during your hardwood floor installation, as well as controlling the humidity levels in your home.

Wood is a natural and very porous material that reacts to changes in the environment when the temperature and humidity levels fluctuate.

Keeping a healthy humidity level in your home is not only important to your wood flooring but also to your overall health in general.

When the seasons change, our hardwood floors are affected accordingly.

Effects of High and Low Humidity on Wood

To better understand how humidity affects a hardwood floor, we need to address the effects of both high and low humidity.

Dry Season with Less Humidity

When the weather is colder outside, we use our heating systems to stay warm. Heat creates dry air, which in turn causes wood flooring to lose some of its moisture.

When a wood floor loses moisture, it shrinks. This shrinkage can cause the following dryness problems on a wood floor:


Dry wood becomes very brittle and weak, increasing the chances of splintering. A common sign is to see a split down the center of a plank in the flooring along the grain.

This cracking causes permanent damage to your wood floor, as the finish on the wood, will also be cracked.


When the humidity level is too low, wood shrinks. This shrinkage creates visible gaps between wood planks.

Gaps are normal in between the wood planks of a floor, and more so during cooler weather when we are using our heating systems more often.

During times when the humidity rises again, these gaps will fill themselves when the wood once again begins to absorb moisture from the air.

Related Article: How Does Humidity Affect the Building Structure of a House?

How to Prevent a Dryness Problem

  • Maintain a recommended humidity level year-round of between 30-50%. This can be accomplished by using either a humidifier or a dehumidifier, depending on the time of year.
  • During the colder time of year when the heat is running, be sure to regulate your in-home humidity levels between 30-50% with the use of a humidifier. This will prevent your floors from drying and becoming brittle.

Humid Season with Higher Humidity

When the weather is warmer during the summer months, the humidity levels will be higher. Hardwood floors will swell and expand to accommodate the absorbed moisture.

This expansion causes the wooden planks on a wood floor to put pressure against each other resulting in an unattractive appearance.


Buckling happens when the wood planks expand beyond the gap allowance causing the flooring to pull away from the subfloor underneath.

The appearance of a buckling wood floor resembles rolling hills in the countryside. The separation between the wooden planks and the subflooring can be as great as a few inches.


Cupping is almost the opposite in the appearance of buckling. When cupping occurs, the edges of the wood planks become higher than the center.

Along with excessively high humidity levels, cupping can also be caused by humidity moving up from a crawl space or basement, or water migrating from a pipe leak.


Crowing is similar to buckling, yet crowning refers to the center of an individual wood plank that rises higher than its edges. Otherwise known as the opposite of cupping.

If a floor has been sanded too soon after cupping, then crowning can happen.


When wood expands due to the absorption of moisture, neighboring wood planks start pressing against each other. This increasing pressure can in turn cause the boards to crack.

Related Article: What Causes High Humidity in a House? Your Questions Answered

How to Prevent a Moisture Problem

  • During warmer weather, leave the A/C on when leaving your home for extended periods of time.
  • When cleaning your hardwood floors, be sure to only lightly dampen a cloth with a recommended hardwood floor cleaner.
  • Use a good quality engineered hardwood floor that will hold up to the stresses of fluctuating humidity levels.
  • Leave a free expansion space around the perimeter of your floor during installation. This space is generally concealed by the use of baseboards.
  • Avoid tracking in excessive water during cold, wet climates.
  • The best way to control the humidity in your home year-round is by the use of an air conditioner or a dehumidifier. You can even try turning on your heating system periodically to dry out the air during the summer months.

High humidity levels may also cause other problems to your hardwood floors that you may not have thought of.

Hardwood Floors Are Prone to Discoloration

Excessive moisture can cause discoloration of a wood’s finish. If you notice a mismatching appearance in some areas of your wood floor, that may be a good indicator of moisture damage.

Humidity Can Cause Fungus and Mold Growth in Hardwood Flooring

Humidity is the perfect breeding ground for many types of fungi and mold. These fungi and molds can damage your hardwood floors, discoloring them and making the wood appear unsightly.

Mold is likely to be growing underneath your hardwood flooring, along with fungi; especially in climates with higher humidity.

Mold gets into the air of a home and can cause health problems such as severe asthma attacks and other allergic reactions.

Related Article: How Does Humidity Affect Furniture? Full Resource

Best Flooring Types for High Humidity

Are you planning on installing new hardwood floors in your home? Well, if you live in a humid area, the humidity could affect your hardwood floors.

Here’s what you can do to prevent humidity from affecting your floors. There are three types of hardwood floors that can stand up to humidity. These include:

  • Brazilian Walnut: This is a beautiful hardwood with light reddish hues. Because of its straight grain pattern, it does not show scratches as much as other hardwoods. This type of hardwood does not warp, expand, or contract as much and does not dent as easily.
  • Quarter Sawn White Oak: Quarter sawn white oak is a hardwood that does not warp easily or swell, even when exposed to high humidity. This type of hardwood does not need as much care or maintenance as other hardwoods, because it does not require much reseal.
  • Quarter Sawn Red Oak: Quarter sawn red oak is a hardwood floor type that does not warp or swell easily. This type of hardwood scratches, dents, and swells up more than other hardwoods but does not require much reseal.

Regardless of what floor type you ultimately decide that is humidity-friendly, it’s also important to consider purchasing an affordable yet good-quality dehumidifier to take control of the humidity levels in your home.

Related Article: If you feel you have high humidity in your home, testing your humidity levels in your home is recommended. Where to Place a Hygrometer in a House?

What is the Wood Floor Moisture Test?

There may come a time when you need to measure the moisture level in your hardwood floor. So let’s learn more. What is the wood floor moisture test?

The wood floor moisture test is a test used to measure the moisture levels in your hardwood flooring by using either a pin meter or a pinless meter that uses either electrical resistance or electromagnetic radio frequencies to measure the amount of moisture in a wood floor.

If you live in a humid environment, it’s important to know that the moisture content of your floors can change depending on the humidity in the air.

If this moisture moves into or out of your wood flooring, you might see noticeable changes in your floors.

Most wood flooring has a recommended moisture content, so it’s important to know the moisture levels of your hardwood floors.

What is the Best Humidity Level for Hardwood Floors?

Hardwood floors can be resistant to changes in humidity levels since we design them with an ideal humidity level in mind. We still need to be aware of an adequate humidity level to ensure the optimal performance of a wood floor. What is the best humidity level for hardwood floors?

The best humidity level for a hardwood floor is between 30-50% to help maintain the integrity of the hardwood floor’s structure. Higher humidity levels can cause cupping, crowning, buckling, and cracking, as well as contribute to a potential mold and fungi problem.

If humidity levels remain within optimal ranges, your hardwood flooring will live a long and healthy life. But when conditions get too high or too low, your flooring could warp, buckle, and crack.

In most cases, humidity affects hardwood floors, but only slightly since we design them with the ideal humidity level in mind.

We often prefer hardwood floors with increased resistance to humidity changes for kitchens, bathrooms, and other areas of the home that might see significant increases in humidity levels.

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Trina Greenfield, Author
SmackDown Media LLC

About the Author:
Trina Greenfield, the owner of SmackDown Media LLC, is passionate about providing information to those interested in the air quality in and around their homes. Trina writes content about things she’s passionate about, such as safe, in-home air, educational platforms for children and adults, as well as all things family-related.