Room
From Unofficial Stationeers Wiki
Purpose[edit]
A Room is a space separated from the world with a "reduced" Atmosphere exchange. If you build a single cube space enclosed with a 6 frames on each side, the game will count it as a room. Doors/portals, even not built fully, will also count as a separation with another room or the world. However a partially built frame or wall if not blocked itself with something else like the ground or another airtight structure behind will connect the room back with the adjacent cell and make your room merge with either the outside world or the room next to it.