For air quality I’m using the arcus neo which can do co2, Voc, humidity and temperature. But they are damn expensive. Unfortunately all the other KNX ones I lo

For air quality I’m using the arcus neo which can do co2, Voc, humidity and temperature. But they are damn expensive. Unfortunately all the other KNX ones I looked at were super ugly/huge. The more ugly ones also had better features like particulate matter as well. These are a super discrete and small brushed aluminium circle on the ceiling. Other than that I have PIR sensors in every room that I mentioned in a sibling comment with presence, temp, light level. One sensor I’m super happy with is the infrasonic water level sensor for the water tank, so I always know how much water I have left. I also have a weather station connected in with a pile of measurements for outdoor stuff like light, humidity, temp, pressure.