Airing out 2-3 times per day for 5-10 minutes is perfectly viable, even in the dead of winter. All windows and interior doors open, get a good flow through the entire house to replace the stale air. Airing out heavily for a relatively short duration keeps the walls and furniture from cooling off, so normal indoor temperature will be restablished in just a couple of minutes, and is vastly superior to leaving a window cracked for hours.