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Bathroom Fans to Control Moisture
Bathroom fans are critical in moving moist air out of a house. If moisture builds up, especially in the warm weather, it creates a potential for mold growth within the space and beyond. If there is laundry in the bathroom or if it is connected directly to a bedroom, it will create a higher potential for mold growth. This risk occurs as the dust and debris of clothes provide the food source and home for mold, with the high moisture content in the air being absorbed by the clothing.
Ideally, bathroom fans are hardwired into the switch to operate at all times and cannot be turned off. Alternatively, fans that have moisture or motion settings are also great options. It is important to get a quiet fan so that no notice is taken when it is running. Fans are rated in "sones" for noise, and the quieter the fan, the better. You can also find some that have external motors, which can be installed in the attic to reduce noise in the bathroom.
According to Canada Mortgage and Housing Corporation, bathroom fans should hold a piece of paper with the draw. This test indicates that the fan has the capability of removing the moisture in an average-sized small bathroom. The fan housing should also be airtight to the drywall, meaning the metal box should be sealed to the drywall with tape or spray foam. Otherwise, the fan could be drawing air from the attic into the bathroom. If this occurs, the efficiency of the unit is compromised, and air quality will be impacted. Consider an Energy Star rated bathroom exhaust fan to ensure you consume the least amount of energy during operation.
The final detail is to ensure that your bathroom exhaust fan exhausts outside and not into an attic or wall cavity. If you skip this step, it can lead to excessive moisture in your attic and mold growth. The ductwork needs to be insulated, tight, ideally solid, not flex duct, and taped at both ends and any elbows or joints. If exhausting through the roof, use an insulated duct. If exhausting out the soffit, make sure the ductwork is below the insulation.
Why not just natural ventilation? Many people will only open a window and consider that to be enough to control moisture. That might work if the window faces the house's downwind side, meaning it will draw the air out. My bathroom window faces west, towards our prevailing winds, so it just blows air in, not out, and doesn't offer much moisture exhaust. Ensure your "natural solution" is, in fact, a solution.
Plants to Control Moisture
Plants are a great addition to any bathroom, especially if you want to make the room a peaceful oasis. Typically, there is enough moisture in the air for many water-loving plants to thrive. They also can improve air quality in a home (as long as they are not overwatered, thereby creating mold).
Try some bamboo pieces in a large floor vase if you can't grow plants. Bamboo is a hygroscopic material, meaning that it will absorb or expel water or moisture from its surrounding environment.
Finishes to Control Moisture
Healthy bathrooms can be beautiful, with elements that resist moisture and rot. Tiles are a great example. When properly installed, tiles should last generations with their beauty and durability. However, durability is only guaranteed when installed on a solid secure tile/cement board. Many, unfortunately, skip this step and install it on drywall or with a simple plastic barrier. Both can lead to water damage behind the tiles and should be avoided. Good quality, low-VOC adhesive, low-VOC moisture-resistant grout, and a low-VOC sealer over your grout will maximize the health of your installation.
Solid wood cabinetry is a better choice than particleboard. It can handle water spills better than pressed sawdust materials.
Clay paints and plasters can help reduce and even out the moisture in your bathroom. They can safely store water from the air when it is damp and release it when it is drier. And - they can add stunning texture and color to the room.
In the winter, hot water radiators help warm tiled surfaces, making the whole space comfortable. Even bathroom towel bars are radiators, delivering warm towels to you simultaneously.
Water Conservation
Water efficiency is a constant issue, as the planet's health needs to be considered, even in your spa. You can save water by purchasing more water-efficient toilets such as dual flush or very low flush toilets such as 4.8L/1.3 gallon-per-flush toilets. Your showerhead, a virtual oasis some days, can also be reduced to even 5.7 Litres per minute or 1.5 gallons per minute. Even at these efficient rates, it will still deliver similar pressure, so you don't have to sacrifice. Keeping the sink tap off while brushing your teeth and getting an inexpensive faucet aerator will reduce your costs and help you do your part to save water. Refer to our rebates page for water-saving rebates in your area.
Bottom Line
I focus on helping homeowners ensure their home remains a healthy place to live in my work. Maintaining a healthy home is one of the primary tenets of a more sustainable home—and the bathroom is a great place to start.
Editor's note: this is a republish of the first in our Healthy Home Series by our expert contributor Stephen Collette. Stephen is a Building Biologist, Building Science Consultant, LEED Accredited Professional, and a Heritage Professional. Stephen is the owner of Your Healthy House and lives in Lakefield, ON, with his wife and two daughters.
Stephen Collette
Stephen Collette is a Building Biologist, Building Science Consultant, LEED Accredited Professional, and a Heritage Professional. Stephen is the owner of Your Healthy House and lives in Lakefield, ON with his wife and 2 daughters.