Floor Discoloration and Mats - What is the Cause?

Every now and then, customers ask why mats cause discoloration on the floors beneath them. This has happened to both carpet and hard-surface flooring, such as vinyl or tile, and the discoloration is usually a yellow or brown color. The primary cause for this is moisture. There are several potential ways that moisture can cause discoloration:

1. Moisture from the ground comes up through the floor until it reaches the floor surface. This moisture normally evaporates and goes unnoticed. Placement of a mat on the floor prevents the evaporation, trapping the moisture and causing the discoloration. This is most common at entrances where cold or warm air enters buildings frequently, causing condensation, or sweating, around the entrance.

2. Placing mats on freshly cleaned and still-damp carpet will make this happen. This prevents carpet and the floors from fully drying, causing discoloration.

3. Moisture from the back of mats can get trapped between the mat and the floor. If not properly dried, the back of mats can be damp, causing even more moisture to discolor the floors underneath.

4. There can also be a chemical reaction between the mat backing and the floors or floor finishes used on hard surfaces. The right kind of rubber backing may prevent this.

5. Lack of exposure to sunlight. It is common to see floors change color when they are covered by counters, file cabinets, and other furniture. This is caused by both lack of exposure to sunlight and restricted airflow along the floors.

In most instances where floor discoloration occurs, the customer is faced with a difficult decision. Remove the mat and the floor doesn't discolor, but will inevitably be damaged by soil, moisture, and dirt. The best compromise is to use a mat and protect the floor with resulting discoloration in the area underneath the mat. The bulk of our customers prefer the potential of discoloration over scratching, dirt, and safety hazards in their establishment.

Corrective actions: Discoloration can usually be removed by stripping and re-waxing. In the case of carpet, professional carpet cleaning is usually required. Our WaterHog series is easy to clean and dry, helping to reduce the risk of discoloration. As always, keep your mats clean and dry, and this will reduce discoloration significantly.