The levels I have at night indeed are unhealthy, I’m still trying to find the best way to tackle this challenge..

Most wakeups are from noise (I can see it in the data) but high CO2 levels can also make me a lighter sleeper.

Not sure where you’re based but in Europe the priority is mostly on heat isolation, so air movement suffers. The US is better in that regard. There was a big thread on that topic on X the other week (Peter the indie hacker initiated it and there were some good recommendations in case you’re the owner of the flat)