Wood Floor Discoloring
Most of the damage done to wood floors, will be in high
traffic areas, like hallways, bathrooms, kitchens, stairs and of course
entryways. Damage could be accelerated if these areas are subject to
moisture. Bathrooms, kitchens and entryways can suffer from staining if
they are not maintained or taken care of.
Make sure that you have something to step out of the shower or bath tub onto to prevent moisture from contacting the wood flooring directly. There are plenty of decorative carpeting is to choose from.
The heavy staining that you're looking at in the picture above is coming out of the entryway, where people remove their wet shoes and clothes before walking through the rest of the home, during damp weather conditions. If you live in areas where it rains or snows often, you could have problems with your wood floors, if they are not maintained properly.
Over time the moisture has stained the wood floor enough that it will probably need to be replaced. Most of the time, you can't sand the stains out of the wood flooring, when they become this bad.
Home Repair Tip - I would remove the wood floor in the entryway and replace it with tile or linoleum. (Do not use smooth tiles or linoleum, these could be slippery when wet) If you like wood floors, I would suggest placing something on top of the floor that would take the brunt of the traffic over time, like a rug with a rubber backing. The rubber backing will prevent the rug from sliding on the smooth wood floor.
Make sure that you check underneath your protective flooring every once in a while, to make sure that there isn't any moisture.