Windows open at night or always shut?

Fresh air quality drops significantly at night in most places anyway. Sealed and filtered beats open and polluted.

Shut windows = lower electric bill + uninterrupted sleep. This isn't complicated.

I crack mine just enough to let air circulate but not enough for raccoons or weirdos to get ideas. Compromise wins.

Depends where you live honestly. City? Shut. Country? Open all night long.

Shut. Noise from the street, bugs, and security concerns. AC exists for a reason.

Open windows at night are non-negotiable for me. Stale indoor air makes me feel trapped and groggy in the morning.