Corner view of a refinished high-gloss maple gym floor with black game lines and PRIDE lettering on the wall

How summer humidity affects gym floors

By John Scillieri Hours Published on

Humidity affects wood gym floors because floor boards can expand as they absorb excess moisture in the air. Summer can be a challenging time for sports facility owners because of higher humidity levels. This is because warm air retains more water vapor and can impact the integrity of your hardwood gym floor. The result can be cupping, crowning, cracking, or buckling.

Maintaining a wooden gym throughout the year is crucial for extending its lifespan. Regular maintenance involves regular dry mop cleaning, occasional deep cleaning, and keeping exposure to water to a minimum. Therefore, you can expect wood flooring in a gymnasium to last between 50 and 60 years under optimal circumstances.

However, it’s crucial to control indoor humidity levels to ensure the wood floor lasts its entire life span. In summer, relative humidity can soar to over 90 percent in some parts of the country. Then in winter, the dry, cool air can create issues because of low humidity.

What steps can you take to prevent a wooden sports floor from suffering damage due to high summer humidity levels? What are the optimal relative humidity levels to maintain a stable environment for hardwood flooring? This article answers those questions and more.

How Humidity Affects Wood Gym Floors

Wood is highly hygroscopic, meaning it absorbs moisture from the air. Therefore, the effect of high moisture levels has a negative impact on hardwood flooring in gyms and basketball courts.

The book “Wood handbook—Wood as an engineering material” says that moisture exchange between air and wood depends on three factors. These are relative humidity, air temperature, and the moisture level in the wood. The effect of seasonal or long-term high moisture loads causes changes in the wood’s structure.

Maintaining an equilibrium moisture content is vital to ensure that high humidity levels don’t affect wood gym floors. This is when the relative humidity and temperature don’t affect the hardwood flooring moisture content.

Professional sports flooring manufacturers typically take into account average humidity levels for the region. For example, summer humidity in the southeastern United States is significantly higher than in the Midwest. However, it is still crucial to prevent humidity fluctuations. 

The Effect of High Humidity on Wood Gym Floors

What does water damage on a good gym floor look like? Here are some ways that humidity affects wood gym floors.

  • Cupping — Excessive air moisture can cause the hardwood floor boards to bend along the edges, creating a “U” shape.
  • Crowning — The effect of humidity causes the floorboard edges to bend down, pushing the center of the board up.
  • Buckling — High humidity causes the boards to expand and push against each other. The wood floor pulls away from the subfloor, creating a bouncy effect when you walk on it.
  • Cracking — Floorboard expansion due to high moisture levels causes boards to expand and crack.

The Ideal Humidity Level For Wooden Gym Floors

Typically, wood flooring manufacturers say that wooden gym floors can cope with a 15 percent fluctuation in humidity levels. This means that within this range, the wood floor won’t experience any adverse problems due to humidity issues.

Therefore, regularly checking air moisture levels during the summer months is crucial. In some cases, intense sunlight and sports activities can cause relative humidity to shoot up in a short time. So, what is the proper humidity level for a wood gym floor? Most sports floor professionals advise keeping air moisture between 35 and 50 percent.

How to Prevent Changes in Air Moisture Content From Affecting Wood Gym Floors

Installing a high-quality hardwood sports floor is a significant investment of time and money. Therefore, humidity controls are crucial to prevent damage to the floor. And as usual, prevention is better than a cure.

Here are a few practical tips on preventing humidity from adversely affecting a wood gym floor:

  • Use a highly-recommended gym floor contractor to install the wood floor. They will ensure there is adequate expansion space between floorboards.
  • Use dehumidifiers and air conditioning to maintain the right temperature and relative humidity indoors.
  • Keep tacking to a minimum during humid weather to avoid excessive exposure to moisture and water issues.
  • Use a hygrometer to monitor relative air humidity and temperature.
  • Sand and refinish a gym floor every ten years to ensure the protective coating protects the maple floor from excessive humidity.

Related reading: Indoor gym floor humidity control in fall and winter.

How to Lower Humidity In Gyms With Wood Floors

Maintaining proper humidity for hardwood floors during summer is crucial to prevent cupping, crowning, cracking, or buckling. If the indoor air humidity in the gym rises significantly above 50 percent, you would need to use mechanical methods to lower humidity. Therefore, you must monitor air moisture and temperature daily to prevent wood gym floor damage caused by humidity.

Use dehumidifiers to lower gym hall air moisture levels

Sucking moisture out moisture-laden air with industrial dehumidifiers can help control humidity levels. The dehumidifying units can work with the HVAC system and come on line when moisture levels reach the critical point. If you only experience short summers, investing in portable equipment may be a cost-effective solution to the humidity issues.

Maintain the correct temperature in the gymnasium

Maintaining the optimal temperature is crucial for protecting the wood floor from expanding and contracting. Ideally, the sports hall should be between 65° and 75°F. Typically in summer, you will need a good air conditioning system to cool the gym, especially if there are windows in the gym.

Keep air filters clean

A good HVAC system that properly maintains humidity levels requires clean air filters to operate efficiently and effectively. Therefore, you should clean or change the filter per the manufacturer’s instructions.

Apart from controlling summer humidity, there is another reason for keeping HVAC filters free from debris. Dust and small particles can make a gym floor slippery and unsafe.

Use proper cleaning methods to maintain the wood gym floor

Excessive moisture from humidity or incorrect cleaning methods can cause irreparable damage to a wood floor. Therefore, you should always use a dry dust mop to clean wood gym floors and only tack the floors when necessary.

Have you noticed the effects of excessive moisture causing damage to your wood gym floor? If so, you should call J&J Gym Floors today at 973-801-7219 or contact us online to get the best advice. Or team of athletic flooring experts is here to advise on what is necessary to restore a wooden sports floor.

John Scillieri

John Scillieri is the Founder and Managing Partner of J & J Gym Floors, bringing over three decades of expertise in hardwood flooring to the sports and fitness industry. Following in the footsteps of his father, a renowned hardwood floor professional, John launched J & J Gym Floors after graduating college, combining rich family tradition with innovative approaches to gym floor installation, maintenance, and customization.

With a passion for quality craftsmanship and a commitment to customer satisfaction, John has led J & J Gym Floors to become a trusted name in the industry. His hands-on approach and deep understanding of flooring technologies ensure that every project, from local school gymnasiums to professional sports arenas, receives the highest standard of care and attention to detail. When he's not transforming gym floors, John enjoys staying active and spending time with his family, always keeping an eye out for the next big trend in sports flooring.