When Outdoor Air is Bad

The biannual reunion for my wife's family was in Kelowna, B.C. this past August and happened to be at the same time as effects from nearby forest fires created, what the news outlets reported as "smoke so thick, it has now led to an air quality index of 10 plus with 10 being the worst it can be". It occurred to me that I have spent much of my 35-year career helping clients find ways of avoiding compromised air quality and now we had intentionally flown in 35 people from ages 5 months to 85 years old to breathe such bad air. My in-laws were interested to hear my take on how best to cope with this type of situation; should we stay indoors and avoid running any ventilation systems to discourage any air entry? The easy answer, of course, would have been to stay away from British Columbia when it was on fire. However, that wouldn't have been an appropriate answer to the millions of British Columbians who had no choice but to stay. The hazy Kelowna sky, pictured here, did spark some healthy conversations about air quality, both indoor and outdoor and prompts me to remind all of us in the HVAC business to educate our clients accurately on the risks and opportunities with respect to proper ventilation.

First, be reminded that since the introduction of important environmental regulations in about the mid-1970's, outdoor air quality in and around major North American cities has improved dramatically. For example, the average number of "smog alert" days has been reduced by as much as 80%. In this way, notwithstanding dramatic events such as this summer's wildfires affecting many places in Canada, outdoor air is usually better than indoor air. Even on those "bad days" your indoor is often worse than the outdoor air. Think about it, the air that is currently in your home came from outside and then you cooked in it, showered in it, breathed in it and so on. Certainly, we can suggest trying to filter the indoor air, but a more comprehensive strategy, that includes the introduction of outside air, is available to you and your clients.

Next, this isn't about tight houses or loose houses, old houses or new houses. In Kelowna this summer all houses, all buildings and all people were affected. Certainly, some more than others - the young, the elderly, the health compromised - but it was noticeable to anyone with a nose, including pets. It was a reminder that control of the quality of air we breathe is important to everyone. That's the key word in this article, control. When the air outside is bad or less desirable, close the windows and stay indoors. But we can't do that forever. Ultimately, we still need some amount of outdoor air and we need to get rid of pollutants that we have created inside. We can't rely on natural leakage through holes in our walls or attics. We can't control direction, or the volume of that natural air movement, and we can't control the quality of that air as it comes through building assemblies.

The indoor air quality professionals reading this article will know the ultimate answer: Build well air-sealed homes, or when renovating older homes be sure to include air-sealing measures. At the same time, include a properly sized mechanical ventilation system that can bring in just the right amount of fresh air and take out the stale air that the occupants create. As that fresh air is being introduced we can condition it, heat it, cool it, manage its moisture content and even filter it. Imagine how nice it would have been for the few people in Kelowna who have an R-2000 home, or an ENERGY STAR home or a Passive home. These would be verifiable tight homes with properly sized heat or energy recovery ventilation systems. Even better off would be those people whose professional HVAC contractor was thoughtful enough to have sold them the top of the line, high efficiency Venmar AVS X-Series ERV with the HEPA filter option.

The Kelowna air problem this summer should also give you a clue as to what to do for your clients who live in old leaky homes anywhere in Canada. It would not have been appropriate for anyone to say, "leave your windows closed for the next 4 weeks in Kelowna". In the same way, it is not appropriate for anyone to live in a building anywhere, at any time without regular introduction of fresh, ventilation air. If your clients don't use windows daily to provide some measure of air quality control, then it is up to you to provide them with an opportunity for controlling the air they breathe. All houses new or old, tight or loose need ventilation; windows can work, but most people don't open them often enough. Mechanical ventilation is a more reliable option. Thus, on your next sales call, at the home shows, or on your website ask your customers if they keep their windows open whenever they are at home. If, like most modern homeowners, they are worried about the noise, dust or energy costs related to open windows, step up and give them back control by installing a properly sized ERV with an efficient filtration option.

This article was written by Gord Cooke, President at Building Knowledge Canada and originally appeared in the Venmar newsletter in 2018.