Discolored Bathroom Grout (Mildew)

Are you seeing a grey or sometimes white discoloration begin to form on the tile grout (the substance that fills the space between individual tiles) or bathtub caulk in your bathroom? Perhaps you see a light dusting on the ceiling or the wall of your bathroom or kitchen? You may think this is mold, but it's not. It's a fungus called Mildew, and it's fairly harmless.

Mildew vs Mold

How do you tell the difference between mildew and mold? Mold generally looks slimy or fuzzy, tends to have a raised texture, and can come in a rainbow of colors, including deep green and black. Mildew is powdery, looks white or gray, always appears flat, and grows on surfaces. A lot of molds smell like dirt. How do you know it's not black mold? It would be extraordinary to find black mold in your bathroom because it cannot grow where there is light. Also, black mold looks very fuzzy, whereas the mildew in your bathroom is powdery.

What Causes Mildew?

Mildew only grows in areas that are damp. It cannot grow in well-lit, well-ventilated areas. The bathroom, especially around the tub is the primary area for finding mildew. Grout is softer than tile and surprisingly porous. Think of it as a hard, dry sponge. Sponges suck in and retain moisture. In a bathroom with mildew, there is no moving air or ventilation steam and water to cause evaporation. Because of that, the tile grout stays wet longer, and this creates ideal conditions for mildew to grow.

How Do I Prevent Mildew?

Turn on the bathroom fan prior to showering, and leave it on for 15-30 minutes after your shower is finished or the bathroom humidity is gone. You can also open the window in the bathroom and leave it open for 15-30 minutes after your shower is complete. Sometimes keeping the bathroom door open during your shower reduces accumulated steam.

Is Mildew Dangerous?

Mildew is not dangerous in the same way that some funguses are, such as black mold. But if you are already allergic to fungus and mold, mildew may experience mild allergy symptoms, such as sneezing and coughing. Most molds are harmless as well, also causing mild coughing and sneezing for those who have allergies. Black mold is dangerous and can cause serious respiratory issues, but again, it is not found in places with exposure to natural light.

Responsibility

If you have mildew in your apartment, removal is your responsibility. We cannot make you turn on the fan or open the window, after all. When you move out of your apartment, you are expected to return it in the same condition as you left it, which includes cleaning the grout. Failure to clean discolored grout can result in a cleaning charge. But don't worry - grout is fairly easy to clean.

How to Clean Mildew

Mildew can be cleaned in three easy steps:

1. Simply mix one part bleach to four parts water.
2. Using a scouring sponge and damp cloth, gently scrub and wipe the mildew until it is gone.
3. Once finished, dry the area well with a soft cloth.

There are also chemicals sold at the supermarket and hardware store that are specially made for cleaning molds and mildews in bathrooms. They typically have bleach in them.

Sometimes the caulk (rubbery sealant where the tub and tile meet) can't be completely cleaned. In that case, we will replace the caulk when we are preparing the apartment for the next resident, at no cost to you.