How clean is the air inside your home? You might want to find out.
BY CAROLYN CAMILLERI
We tend to think of pollution, airbourne allergens and contaminated air as something that happens outside. Sure, we notice indoor odours, good and bad, but unless we are varnishing woodwork or cooking something aromatic, we may not think about the air in our homes at all. Or at least, we didn’t until the pandemic.
Reader be aware: The following reality check may cause you pause, but the good news is solutions abound, and they have everything to do with the importance of hidden infrastructure — like ventilation.
Germs and allergens that affect health, as well as moisture and mould that deteriorate a home’s structure, can be lurking inside a home at significantly higher levels than you might imagine. That’s not all: dust, wood smoke, fumes from craft supplies and cleaning products, and even carbon monoxide, radon, asbestos and formaldehyde can be unexpected house guests.
“A home can have more pollution indoors than in downtown New York,” says Don Gulevich, owner of Coastal Heat Pumps.
He’s not exaggerating. According to studies by the United States Environmental Protection Agency, the air inside a home could be two to five times more polluted than outdoor air. How at-risk you are and from what depends on a number of factors, but indoor air quality is serious enough that the Government of Canada has online resources devoted to the subject. It’s an even greater worry with increased flooding, forest fires and allergens resulting from climate change.
One of the biggest sources of indoor air contaminants, however, is new and newly renovated homes.
“There’s so much in the building materials in the construction of a home, and they’re called VOCs — volatile organic compounds,” says Gulevich, listing culprits like the binders in glue for cabinets and woodwork, countertops, carpets, paints and finishes. “You know that new-home smell? That’s just all the stuff gassing off.”
Indoor air quality can be further affected by the increased emphasis on reducing energy use and preventing heat loss by sealing drafts, improving insulation and upgrading doors and windows. Yes, we absolutely want to do this — but if we aren’t partnering this with appropriate ventilation, we can run into trouble.
Go with the air flow
Ventilation is important for maintaining air quality, ensuring a comfortable temperature and managing moisture. At a basic level, it’s about moving the air.
“This is why I’m such a proponent of forced-air systems,” says Gulevich. “You can do things with the air — you can purify the air, you can filter the air, you can humidify it and just circulate the air. It’s so important for your own personal health, but also for the health of your home.”
Forced-air systems use ducts to push air throughout the home. Heat pumps, conventional furnaces and built-in air conditioners can all be considered forced-air systems.
“Some may think just from the name ‘forced air’ that it’s noisy. It isn’t,” says Gulevich. “But just that alone — having the air filtered and circulating, the temperature even — has a huge effect on air quality. It’s not sitting stagnant.”
Filter care in a forced-air system is a critical part of maintenance. Filters should be high quality and changed often — even quarterly, in some cases.
“Think about it. What would you like the filter to do? Clean the air. If it gets dirty in two or three months, then it’s doing what it’s supposed to do,” he says.
System maintenance is another regular consideration to avoiding costly problems. No matter what kind of system you have, an annual checkup by a professional is strongly recommended.
“It’s like having an oil change on a car,” says Gulevich. “A good quality heat pump system should last you 20 to 25 years, but if you don’t maintain it, you’ll have problems within 20 months.”
Getting expert help
In a perfect world, we would have all home functions like heating, ventilation and air conditioning checked regularly. In reality, we may wait until we have a problem.
These problems are often apparent — like clay in a crawl space with no moisture barrier, allergens in a home where occupants have respiratory issues or moisture that causes visible mould. Yet sometimes, Gulevich says, they go unnoticed.
In one home he visited, heat was produced primarily from electric baseboard heaters. To conserve energy, the door to one unused bedroom was closed and the room’s heat was turned off. When he looked inside, water had condensed on the windows and a band of black mould had formed where the wall met the ceiling. The room had become a health hazard and the structure of the home itself had been compromised.
When people call for guidance, assessments start with questions for homeowners.
“The first question will be about what kind of heating system they have now,” Gulevich says. “Is there duct work or not?”
If there is concern with particulates in the air, then it’s a discussion about filtration systems. If there is concern about germs and viruses, then it’s about air purification. If a homeowner is wanting to change their heating system, the discussion is about new options. If they specifically don’t want that change (or can’t because they are in a condo), the discussion is about portable air purification systems and ductless heat pumps.
A system meant to vent
Converting a home from electric baseboard heaters to a heat pump system is a daily occurrence at Coastal.
“As soon as you shut off your baseboard heaters and turn on your heat pump, you’re going to be dropping your heating bill by at least 50 per cent,” he says. “You’ll immediately start filtering the air, you’ll immediately start circulating the air and you’ll immediately be eligible for rebates.”
He notes that installing air ducts into a home that doesn’t have existing ducts is a bigger and more costly project, but is doable. In rare cases, where ducts can’t be added everywhere, a combination of ducted and ductless heat pumps is recommended specifically because of the air flow they create.
The other bonus in shifting to a forced-air system is that, despite the name, heat pumps also cool a home — something Islanders have grown to appreciate in recent years.
“If you set your thermostat for 22˚C, then forget about it, you will be absolutely amazed at how comfortable your home is,” Gulevich says.
And with a ventilation system operating year-round, you’ll have the peace of mind of knowing the air inside your home is fresher and cleaner — sometimes, even more so than the air outside.
What does it mean to have proper ventilation? Here’s a quick breakdown to showcase a few options.
Natural ventilation: This occurs when outdoor air enters through windows and doors and flows freely into your home. How well natural ventilation works depends on the ability to create a cross-breeze, when outside air comes in through one opening and pushes inside air out through another opening. The downfalls: doors slam, papers blow off tables, and there goes your heat in the winter and your AC-cooled air in the summer.
Relying on natural ventilation may mean uneven temperatures, security issues and unfiltered air from outside, which presents particular risks with allergens, forest fires and high-traffic areas.
Mechanical ventilation: This recreates natural ventilation using fans that either push old air out (exhaust fans) or bring fresh air in (supply fans). Relying on exhaust-only ventilation goes against modern building codes for very good reasons. Solely using exhaust-only fans can create negative pressure (compared to outdoor air), which can backdraft fuel-fired appliances, fireplaces and woodstoves.
Supply fans are commonly used with furnaces and deliver warmed, filtered fresh air through ducts. For this system to work best, exhaust fans, especially in bathrooms, kitchens and laundry rooms, are needed to prevent positive pressure — a condition that can cause condensation, mould and damage to the home structure. For this reason, supply-only ventilation also does not meet modern building codes.
The goal, of course, is to achieve balanced ventilation using both exhaust fans and supply fans to ensure good air flow and prevent pressurization and depressurization.
“As soon as you shut off your baseboard heaters and turn on your heat pump, you’re going to be dropping your heating bill by at least 50 per cent.”
Air Flow Quick Tips
• Open windows to create a cross breeze where possible, or create a chimney effect by opening one window on the ground floor and another on an upper floor.
• Check exhaust fans in bathrooms, the laundry room and kitchen to ensure they are clean and in good working order. Consider upgrading to automated fans.
• Clean portable fans regularly, as well as window screens.
• Keep your ventilation systems clean and well maintained, including filters and ducts.
• Check your dryer vent to make sure it is clear and able to vent to the outside.