This house is superinsulated with airtight construction methods. I was delighted at the opportunity to look inside the walls but depressed at the reason why.
You can control the bath fan and the light from the switch, automate with motion and sensor controls, or you can mix and match methods. You can even tinker at the switch
It's easy to air seal the middle of the wall where there are no gaps, cracks, or joints. The edges are a different story, especially when one edge is wood and the other is concrete.