After the Flood, Should I Remove the Floor Tile or Just Regrout?

After any flooding event, homeowners are faced with the daunting task of deciding what to do to recover their losses, and, more often than not, the decision is based on money instead of what might be best.   When it comes to potential health concerns, money should take the back seat.  

Did you know there is a small space between your floor tile and the concrete subfloor?   Typically, floor tile is set in a thin layer of mortar called “thin set” and this mortar is applied with a grooved trowel.   Those grooves in the mortar sometimes flatten out when the tile is installed but there also remain areas where water could pool.   Wherever water pools, mold may grow so making sure that all areas under the tile are dry before reoccupying the space is important.   Drying and treating these areas are especially important when dirty flood waters have penetrated the floor.    

The nationally recognized IICRC S-500 classifies water loss into three (3) categories to help assessors, restoration, and remediation contractors evaluate the contamination level of the water.   By categorizing the water event, a protocol for cleanup can be established that will reduce the possibility of microbial contamination which could lead to potential health issues.      

Category 1 is “clean water” from a source that poses no substantial harm to people.   The bathroom sink you were filling runs over and floods your bathroom floor.   That would be Cat 1.   Category 2 is “grey water” which poses health risks due to significant levels of contamination of bacteria, mold, and/or chemicals.   You had put a cup of bleach in that bathroom sink you were filling, so now the flood in your bathroom is considered a Cat 2 event.   Now suppose that after you used the commode, the toilet overflowed and flooded your bathroom floor.   This would be Category 3 “black water” because it contains disease-causing organisms, and toxins, and is grossly unsanitary.   You can see how knowing how to classify the water loss would lead to a more successful resolution of the problem.    

In August 2016, Louisiana experienced one of the worst floods in its history.   Prolonged rainfall from an unpredictable storm resulted in catastrophic flooding where thousands of homes and businesses were submerged.   In Denham Springs, just outside of Baton Rouge, caskets were seen floating down Main Street.   How would you categorize that water loss?   It was definitely Cat 3.  

When flooding occurs, especially as the result of a hurricane, Cat 3 water is the result.   This means that wherever the water goes, it takes microbial contamination.   To be specific, that water could seep in from multiples places: through the slab, if there is a breach in the vapor barrier, through cracks in the grout or tile itself, in the spaces between the subfloor and tile at the perimeter, or under a toilet or cabinet where the tile did not extend to the wall.   Why is this a concern?   Because any microbial contamination that remains could present future problems and potential health issues to the occupants.   So, what is the solution?  

Anything short of removing the tile is, in our opinion, asking for future problems.   Even efforts to remove the grout, dry, treat, and regrout are fraught with potential problems because of the many places where microbes can hide. Removing the tile, professionally cleaning, disinfecting, preventative treatment, and reinstalling the tile is best for the occupants.   Yes, there are many band-aid solutions, but doing it right is always best.