Discoloration

Discoloration of wood flooring is often caused by rugs on the floor. Rugs can cause a variety of problems. The rugs block the UV light causing uneven fading. Rugs can also bleed an oil onto, or into the wood flooring. If the rug area is oily, then it can usually be wiped off with wood floor cleaner or dish soap and water. If the oily residue is gone from the surface and the floor is still discolored, then oil has seeped into the finish and the floor will need refinishing to correct the problem.  

Discoloration can also be caused by the finish darkening with time. Some water-based products may not darken and others just darken slightly. Oil polyurethane finish darkens and gets more orange with time and exposure to UV light. The amount of color change is directly related to UV light intensity and exposure.  

The wood itself will also change color over time. A few woods like, Cherry, Pine, Tigerwood, Brazilian Teak (Cumaru), Brazilian Walnut (Ipe), and Brazilian Cherry (Jatoba) will darken with time and exposure to average UV light. Most other woods will lighten with time and UV exposure. For example, a standard red oak floor will initially be darker and more varied in color. As it's exposed to more UV light, the finish will darken slightly but the wood will bleach out and lighten. Everyday, direct sunlight will drastically lighten the floor to a point that it's pale without its original color variation. Once the finish or wood has discolored there are only two options: Wait months or years for the fading to equalize throughout the entire floor, or sand the floor and hope the wood discoloration is shallow so it can be removed. To prevent discoloration, check and move rugs more often with flooring that receives direct sunlight. The cross-grain fading line shows the most.  So make sure to move the rugs with the grain to lessen the fading line that develops across the grain. It's also recommended to completely remove the rugs for 1-2 months of the year to minimize fading lines.