MDF stands for Medium Density Fiberboard and it is a common practice to use MDF for baseboards throughout the house. MDF has one extremely big flaw in that it is essentially a compressed cardboard type of material. When the MDF gets wet it will swell up and expand like a balloon. When the MDF expands the paint will chip off of the MDF and the MDF will look bloated and ugly. After the MDF expands and then dries it will not regain its original shape and it will become permanently bloated, deformed and basically ruined. Sometimes people try to sand down the MDF and paint it but the baseboards will never look as flat and evenly shaped as they were when they were first installed.
The possibility of ruining their baseboards when cleaning a tile floor creates a dilemma for people who want to clean their tile and grout but do not want to ruin their baseboards. Water and cleaning chemicals must be used to effectively clean any dirty surface and cleaning tile and grout is no exception. Some people will attempt to put blue painters tape on their MDF to protect it from water getting through the MDF. Blue painters tape will absorb water and the water will soak into the MDF relatively easily. Also when you remove the blue painters tape after cleaning the tile and grout the blue painters tape can pull off the paint making the MDF baseboards look ugly. Using a waterproof tape such as duct tape will provide better protection from water getting on the surface of the baseboards when cleaning the tile and grout. The problem with using duct tape is that water can still get under the MDF baseboards and make them swell up and deform. Also duct tape will definitely pull away all the paint that was applied to the MDF.
Taping off MDF baseboards before cleaning a tile floor is not an adequate solution to protecting the MDF baseboards when trying to clean the tile and grout. One solution to protecting MDF baseboards when cleaning the tile floor is to apply silicone caulk between the MDF baseboards and the tile and grout. The silicone caulk will prevent any water from getting under the baseboards and causing them to swell up and get ruined. Caulking the bottom of the MDF baseboard will not prevent water from getting on the surface of the MDF but most of the water damage to MDF baseboards is done when water gets under the MDF baseboard. The bottom of MDF baseboards is not painted and there is nothing there to protect them from absorbing water.
Caulking the bottom of MDF baseboards before you clean the tile and grout may be an adequate solution but it requires a lot of time and effort to caulk the MDF and also you must wait 24 hours for the caulk to dry before cleaning the tile and grout. Caulking a tile floor and waiting 24 hours for the caulk to dry may not be an acceptable way to protect the MDF when cleaning the tile and grout. Another solution is to carefully control the water and cleaning chemicals when cleaning the tile and grout.
You can carefully clean a tile floor with MDF baseboards by being extremely careful with the water and cleaning chemicals. You should use a scrub pad when applying the cleaning products to the edge of the tiles where they meet the baseboards. It is important to only use a small amount of cleaning solution and you should use paper towels or a cotton towel to wipe away any excess water and cleaning solution before they get under the MDF baseboards. Being extremely careful in this way takes a lot more time to clean the tile floor but it will prevent you from ruining your baseboards while cleaning your tile and grout.