Prevent Mold With Good Bathroom Ventilation

Bathrooms … they’re supposed to be a little wet and steamy, right? While you shower and bathe, of course! But excessive moisture that lingers in the bathroom can be an indicator of poor ventilation — and create additional problems in your home, such as mold and rot. Learn how to spot the signs of poor bathroom ventilation and how to fix the problem before it damages your home and health.

Warning signs of improper ventilation

If you have problems with the buildup of excess moisture, some warning signs have probably been gathering steam over time. Check for these red flags in your bathroom, which indicate you might have poor ventilation:

  •      Stains on the walls or ceiling
  •      Peeling paint or wallpaper
  •      Pipe condensation or corrosion
  •      Frosty windows
  •      Mold
  •      Excessive humidity

Examine your toilet and the pipes behind it, along with the plumbing beneath your bathroom sink to see if condensation has collected.  A sweaty toilet or sweaty pipes can indicate other problems — like a toilet flush valve leak or the need for some pipe insulation — but can also be a sign of poor ventilation in the room.

Video: How to fix a sweaty toilet

DIY tip: Replace your toilet flush valve and add some insulation to your toilet pipes to see if that helps your moisture problem. If issues persist, or you have multiple signs of poor ventilation, consult an expert plumber based in Maryland or Virginia.

Common reasons for poor bathroom ventilation

According to the International Association of Certified Home Inspectors, the improper termination of the ventilation system duct is often the cause of excessive retention of moisture in the bathroom. Ventilation systems should vent to the exterior of the home, but many times are improperly routed to the attic, into insulation or underneath attic vents. This could mean a buildup of mold and rot not only in your bathroom, but in your attic, behind your walls and and in areas of your home that you can’t easily see.

Your vent may also have a buildup of dust or debris, which can prevent the system from functioning properly.

DIY tip: Try cleaning the vent. If that doesn’t help your moisture problem, get an expert opinion.

Note: Older bathroom fans tend to be noisy, and one that runs quietly may not be functioning properly.


Potential problems of moisture buildup

Not only are bathroom mold and mildew just plain ugly and icky, their growth can lead to other issues and pose health risks. Inhaling mold spores proves especially dangerous for those with asthma, allergies or compromised immune systems. Some healthy people just have a sensitivity to mold as well, according to the Centers for Disease Control. Potential reactions to exposure can include:

  •      Stuffiness in the nasal passages
  •      Irritation in the throat, nasal passages or eyes
  •      Coughing or wheezing
  •      Skin problems

Mold often has an unpleasant, musty smell. If no mold is visible but you still have a musty smell in your bathroom or other areas of your home, mold is probably growing behind your walls, in your attic or somewhere else you can’t see. 

DIY tip: If a visible area of mold is smaller than 10 square feet, clean it using a regular household cleaning product or a mixture of bleach and water while wearing nonporous gloves. Cleaning is just a first step, though — you will still need to address the source of the mold.

In addition to mold, moisture buildup leads to rot. Even if rot or deterioration isn’t visible in your bathroom, improper ventilation could be causing structural damage inside your walls, especially if your bathroom ventilation system isn’t installed properly. It can damage drywall and also insulation, which can negatively affect your home’s energy efficiency.

Learn about your bathroom’s plumbing system


How to fix poor ventilation

To function properly, bathroom ventilation ducts should be as short as possible, be insulated and extend several inches from the exterior of a home. If you have an older ventilation system that doesn’t appear to work properly, you should have a pro check the ducts. If they twist and turn on their way to the exterior vent, joints could have loosened or come apart, impeding function of the system. And again, if the ducts don’t terminate out of the exterior of the home, you will need to have them properly vented.

If your bathroom doesn’t have a ventilation duct or a window that allows moisture to escape when you shower or bathe at all, you’ll likely need to have one installed. Just having a vented window is impractical in areas of the country with cold winter weather.

New bathroom ventilation and fan systems have some great advantages over their predecessors. Typically, they run more quietly than older models. Some also come with timers or humidistats that will automatically engage when the environment reaches a certain level of humidity. Talk to a professional about what will work best in your home.

DIY tip: Take shorter showers and leave doors open when bathing, if possible. Wipe any condensation on tiles, walls or other surfaces after bathing. Remove carpet, which traps moisture, from the bathroom. You can also purchase a bathroom dehumidifier to help eliminate moisture, although a ventilation system is the best and most thorough way to keep moisture in your bathroom at bay.

The residential plumbing experts at John C. Flood can help assess and repair bathroom ventilation problems you have in your home in the D.C. metro area, including D.C., Maryland and Virginia.

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