Improve bathroom ventilation to control humidity

Run the exhaust fan during every shower or bath and keep it on for 20-30 minutes afterward to flush out humid air. If no exhaust fan is installed, open a window. On persistently humid days, a portable dehumidifier helps keep moisture below the 50% threshold where mold thrives.

Why It Works

Mold requires sustained moisture, warmth, and organic material to colonize. Removing humid air quickly after bathing eliminates the primary condition mold depends on, making it far harder for spores to take hold on grout, caulk, and other surfaces.

Tips

• Clean the exhaust fan cover and blades every few months to maintain strong airflow
• Verify the ductwork vents outdoors, not into the attic, where it would simply relocate the moisture problem
• Replace an underperforming fan with one rated for your bathroom's square footage (1 CFM per square foot is the standard minimum)