Just open a window a crack. The CO2 drops rapidly.
The problem with ultra insulated homes are that C02 and moisture get trapped. So then you need filtered fresh air, and then heat recovery.
The problem with ultra insulated homes are that C02 and moisture get trapped. So then you need filtered fresh air, and then heat recovery.
There's also other reasons - for example I want to ensure the flow of air through the house concentrates and exits via the bathrooms and kitchen.
I've been tracking my home office's CO2 level for about a year and a half and obviously opening a window helps, but there are certain conditions (pressure, temperature, wind?) that require fans to normalize the levels.