Do Martial Arts Mats Expand Or Contract?

When using EVA foam interlocking martial arts mats in a studio, you may notice an expansion of the materials in warm conditions or when exposed to bright sunlight. Although not very common, the foam material may also contract when exposed to cold conditions. So yes, martial arts mats may expand or contract.

Fortunately, you can take multiple steps to reduce the possibility of having a problem with your interlocking tile layout from excessive expansion or contraction.

What a Buckled Foam Floor Looks Like

If individual tiles are expanding and bunching after you connect them in the layout, the seams on the interlocking tiles will bear the brunt of the force of the expansion.


This force may cause the seams to pop loose, meaning the edges of one or more tiles rise upward. The centers of the individual tiles may also bubble upward if the flooring has a buckle.

Steps to Take to Avoiding Buckling Foam Flooring Tiles

When installing martial arts interlocking tiles, you can follow a number of steps to reduce the chances of having a buckled floor.

Leaving a Gap at the Edges

During the installation of foam floor tiles in a wall-to-wall layout, you must leave a slight expansion gap at the edges. In other words, don’t put the exterior of the tile layout tight to the walls.

Typically, you should leave a 1/2-inch gap, which gives the foam tiles the necessary space to expand slightly without buckling. Read the installation instructions for your particular product to determine the exact size of gap to use.

Some home or studio owners dislike leaving a gap at the edge because it could collect dirt or other particles. However, it’s vital for creating a longer-lasting layout.

Using Larger Tiles

If you will be creating a layout that has more than 400 square feet of connected tiles, we recommend only using large-sized foam interlocking tiles measuring 1x1 meter.


A 2x2 foot tile is going to have a greater chance of buckling than the larger 1x1 meter tile has.

Avoiding Sunlight Exposure

Direct sunlight coming through a window of the martial arts dojo tends to increase the chances of buckling in the tile layout. When the sun hits the EVA foam material, it heats the foam quickly and can result in buckling.


If you have a room at the studio that tends to receive a lot of sunlight, you may want to avoid placing foam flooring in this room. You also could install a window shade to create limited direct sunlight exposure for the foam.

Maintaining a Consistent Temperature

If you want to avoid a buckling floor in your studio setting, only install puzzle-style foam tiles in a room or building that has air conditioning for the summer and heating for the winter.


A building that doesn’t have temperature control will expose the foam to excessive warmth and cooling, increasing the chance of expansion, contraction, and buckling.

Additionally, a building or room without air conditioning could have quite a bit of humidity in the air, leading to expansion.

Creating an Island Installation

Rather than installing the foam floor in a wall-to-wall layout, you could design an island installation. This means that the layout is in the middle of the room or only against one wall, rather than within a fraction of an inch of all four walls.


Some models of our foam tiles have border pieces that fit into the puzzle edges of the main tiles, creating a flat, finished edge that’s ideal for use in an island installation.

How to Fix a Foam Flooring Layout That’s Buckling at Your Martial Arts Studio

Cut the edges of the tiles with a utility knife to shrink the size of the layout by 1/2 of an inch on all four sides of the room so it does not touch the walls.

Why Martial Arts Mats Suffer Expansion

Several conditions can cause EVA foam tiling to expand, which may result in buckling along the seams of the connected puzzle-style edges. This causes a tripping hazard and a loss of integrity in the layout.

• Increased temperatures: If you are installing the flooring tiles in a martial arts studio that doesn’t have temperature control, the foam will expand as the temperature rises.
  
• Increased humidity: EVA foam also can expand slightly when exposed to a space where the humidity level in the air increases beyond normal levels, such as on a hot summer day.
  
• Direct sunlight: If the flooring layout receives exposure to the sun during the day, either directly or through windows, the increased heat from the sun could result in expansion.
  
• Normal Use: Foam tiles may expand slightly with regular and continued use and this is normal. In very high-traffic areas they may expand faster.