HVAC & Mechanicals
The nuts and bolts of ducts and volts
Soffits should be tight boxes hidden in your ceiling.
But some buckets are more relative
New energy codes are coming (very) soon; many states are jumping straight to the most aggressive one
All clothes dryers should vent directly outside.
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