How to Treat Hardwood Floors That are Turning Gray

Take out all furniture and other removable items and ventilate the room. Cover light fixtures and outlets. Put on safety gloves and a construction mask to cover your nose and mouth.

Sand the floor to remove the previous finish. Use a belt or drum sander with a 36-grit abrasive. Sand in the direction of the flooring, next at an angle and finally across the boards.

Sand the edges of the room with an edger. This machine is smaller and fits into spots the belt or drum sander doesn't. Use a 36-grit abrasive.

Vacuum the floor thoroughly, and repeat the sanding with the belt or drum sander and the edger, this time using a slightly finer 50-grit abrasive.

Vacuum the floor. Repeat the sanding, edging and vacuuming one more time with an 80-grit abrasive.

End the sanding by buffing the floor using a 100-grit abrasive to further refine the surface. Vacuum well.

Apply the sealer or stain with a roller applicator. Use a paintbrush for edges and hard-to-reach areas. Let the sealer or stain dry completely. The length of drying time varies with the chosen finishing product.

Sand the dried finish with 150-grit abrasive, then vacuum. Repeat the application of sealer or stain and let it dry. Sand and vacuum again. Apply a third and final coat, and let it dry completely before moving the furniture back in.