Checklist: Moisture Problems in Bathrooms
Bathrooms generate a good deal of moisture through showers and bathing. Ventilation is important.
- Condensation on windows.
- Condensation or staining on walls or ceilings.
- Water dripping from exhaust fan grille.
- Mould between ceramic tiles.
- Rotting windowsills.
- Damaged gypsum board under windows.
- Bulging gypsum board.
- Peeling paint or wallpaper.
- Musty smells.
- Visible mould damage, staining or growth on floor or carpet.
- Curling floor tiles.
- Loose floor and wall ceramic tiles.
- Water pooling around toilet, sink or tub.
- Toilet is unstable — moves easily.
- Mould on walls or ceiling.
- Condensation on toilet tank.
- Mould under toilet tank.
- Leakage, spillage from bathtubs and shower stalls during use.
- Moisture (often referred to as “steam”) from hot baths and showers.
- No bathroom fan.
- Bathroom fan not used.
- Uninsulated exhaust fan duct — condensation forms in cold duct.
- Backdraft damper on exhaust fan housing inadequate — allows cold air in from outside when fan not operating, which cools surfaces and makes them prone to condensation.
- Leaky plumbing.
- Plumbing leaking behind walls.
- Dampness from wet bath mats, towels and drying clothes.
- Inadequate air circulation.
- Temperature kept too low/poor heat distribution to bathroom.
- Seal lost around shower stall or tub, cracks in tiles.
- Uninsulated toilet tank resulting in cold tank surface and humid weather condensation problems.
- Turn on exhaust fan when showering or taking a bath.
- Install a bathroom fan exhausted to outside (windows are not a reliable source of ventilation).
- Allow fan to run for 15 minutes or longer after the shower or bath to remove moisture.
- Squeegee or towel dry surfaces in the shower stall or bath enclosure after use.
- Close bathroom door and run bathroom fan when showering.
- Install a humidistat that turns exhaust fan on and off automatically.
- Fix leaky plumbing.
- Supply adequate heat and ventilation to the bathroom.
- Caulk joints in shower stall, tub and around sink. Repair/replace/seal grout joints in tiled floors and walls.
- Properly insulate walls and ceilings.
- Consult a professional contractor for replacement of mouldy walls.
- Have insulated exhaust fan ducts properly installed.
- Remove carpet.
- Install a 4.5-litre (1-gallon) toilet — these do not tend to “sweat” as they hold less cold water.
- Clean surfaces regularly.