made a new friend while exploring the lush caves (i called him Zomb)

Smart vents

One thing that I never saw before in houses before moving in Holland are aeration vents in almost all rooms (see picture). One thing that worries me is that even when they are closed, during the winter, they can let cold pass, impacting the temperature inside the room. One thing that I was wondering is any one ever replaced them with some sort of sealing smart vents - something similar to the one in the toilets, but that can "properly" close and that open and make air circulate when needed (ideally when the level of CO2 or humidity are too high for example). Curious to know solutions that other found!

PsBattle: hello there

PsBattle: Mike Pence praying with Senate candidate John James of Michigan

PsBattle: Blue Jay

PsBattle: Disc golfer

PsBattle: Praying mantis

PsBattle: This baby Monarch caterpillar.

PsBattle: A tuxedo cat wearing a bow tie

PsBattle: a tired cat that yawns

PsBattle: Buzzy Bee Bike