The Causes of Bathroom Mold and Mildew
Mold and mildew in the bathroom can be caused by a variety of factors. The main causes are excess moisture, lack of ventilation, condensation, leaks, and high humidity.
Moisture is the number one cause of mold growth. When surfaces like shower walls, ceilings, windows, and tile grout remain wet for prolonged periods, mold spores are able to germinate and grow. Common moisture sources include steam from showers, baths, dishwashers, washing machines, as well as leaks from plumbing or roofs.
Lack of ventilation also encourages mold growth. Bathrooms need proper air circulation to remove humid air and prevent condensation buildup. Insufficient exhaust fans, small windows, and poor airflow allow humid conditions to persist.
Condensation on cold surfaces like windows and mirrors provides the perfect damp environment for mold to thrive. This often results from steam, humid air, and poor ventilation.
Leaks from showers, sinks, tubs, and roofs can soak into walls, floors, cabinets, and ceiling surfaces leading to mold growth. Any water intrusion needs to be stopped and dried completely.
High humidity levels above 55% also promote mold growth. Bathrooms tend to have higher humidity than other rooms due to their frequent use and all the moisture generating activities occurring. Controlling household moisture and humidity is key for prevention.
How To Get Rid of Existing Mold
If you already have bathroom mold, getting rid of it completely requires killing the mold, removing the stained surfaces, fixing the moisture source, and taking preventative steps. Here is a step-by-step process:
Step 1: Put On Protective Gear
- Wear gloves, goggles, and an N95 mask to protect yourself from mold spores and harsh cleaning chemicals. Limit exposure when cleaning.
Step 2: Kill and Remove Mold
- Kill mold by spraying affected areas with an EPA registered mold and mildew cleaner or bleach solution.
- Scrub surfaces with a stiff brush or scouring pad to remove stains and mold residues.
- Completely dry areas to remove all moisture after disinfecting.
Step 3: Identify and Fix Moisture Sources
- Find and repair all leaks causing dampness.
- Improve ventilation and air circulation with exhaust fans and opening windows.
- Insulate cold surfaces prone to condensation like pipes and windows.
Step 4: Replace Porous Materials
- Remove and replace any porous moldy surfaces like wallboard, insulation, carpet, and ceiling tiles.
- Mold can spread and grow inside these materials even after cleaning.
Step 5: Apply Mold Inhibiting Paints
- Use mold resistant paints containing zinc oxide or other additives on cleaned areas to help prevent regrowth.
- Primer with microbial properties can also be applied before painting.
Step 6: Disinfect the Whole Area
- Disinfect counters, floors, walls, and other bathroom surfaces with diluted bleach. This kills lingering mold spores.
- Wash towels, mats, and shower curtains in hot water to eliminate mold and mildew.
Prevention Tips and Solutions
Preventing the recurrence of bathroom mold involves controlling moisture and limiting mold growth conditions.
-
Install exhaust fans that actively vent humidity out. Run them during and after showering for 20-30 minutes.
-
Keep bathroom doors closed and run fans when showering or bathing to contain steam.
-
Open windows to improve airflow and ventilation when possible.
-
Use mold resistant paints and caulks which contain fungicides. Apply to moist areas prone to mold like shower walls.
-
Clean bathrooms regularly with disinfectants containing bleach to kill mold spores and inhibit regrowth.
-
Dehumidifiers help maintain optimal humidity levels below 55% throughout the home.
-
Clean seals and grout with bathroom mold cleaners or diluted bleach regularly. These are common mold sites.
-
Fix leaks and drips right away and dry out any soaked materials. Eliminate moisture sources.
-
Insulate pipes and windows with insulation wraps and film to reduce condensation.
Stay vigilant in moisture control and immediately clean any new mold growth. With diligent prevention habits, you can successfully conquer recurring bathroom mold.
