Following our recent webinar on ventilation and airtightness, we received some feedback that I think is important to share.
As a listener pointed out; “Indoor air quality is almost entirely dependent on intentional ventilation, uncontrolled air leakage has virtually zero correlation to indoor air quality. So, a building being air leaky or airtight means nothing in terms of ventilation.”
They emphasised that airtightness can help to improve the effectiveness and efficiency of mechanical ventilation.
Both airtightness and true mechanical ventilation with heat recovery (MVHR) are in their infancy in New Zealand, especially when compared to other countries such as North America, Canada, the UK and most of Europe.
We want to encourage the uptake of both mechanical ventilation and airtightness, so it’s important that we get the message correct.
When discussing ventilation and airtightness with clients and colleagues, we need to be clear.
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Homes need mechanical ventilation for a reliable and consistent indoor air quality.
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Airtightness helps protect the durability of a building, the health of the occupants and the building’s energy efficiency.
Well-designed, effective ventilation and airtightness work together to provide a healthy and efficient home, but one is not dependent on the other. Effective ventilation is a requirement for a healthy building. Airtightness reduces the uncontrolled flow of moisture and energy.
For more on this topic, check out:
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This blog and this blog by Kara Rosemeier Director at Passive House Academy New Zealand - Kaiako Pūtaiao Hanganga
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This blog post by Elrond Burrell
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The Impacts of Air Leakage Paths and Airtightness Levels on Air Change Rates