Indoor air quality testing

Because a tighter house is only a better house if it is ventilated properly.

Every retrofit that reduces air leakage reduces the accidental ventilation that leakage was providing. Done well, that is the point — you replace uncontrolled infiltration with controlled, filtered, heat-recovered ventilation. Done badly, you get a house that is cheaper to heat and worse to live in.

We test for the things that actually change: carbon dioxide as a proxy for whether the ventilation rate is adequate for the number of people in the house, relative humidity and where it is condensing, particulates, and combustion safety.

Combustion safety is the one we will not skip. A naturally drafted gas or oil appliance in a house that has just been air sealed can, under the wrong conditions, spill combustion products back into the living space. A depressurisation test tells you whether that is a risk in your house before it becomes one.

Wildfire smoke has made this a live question in a way it was not five years ago, particularly in British Columbia and Alberta. Filtration and a sealed envelope are a genuinely effective defence, but only together.

For homeowners — the rest of it