Closed and Open Door .
Doors are a very common and useful piece of furniture. They can be made from 8 boards which need to be in the player's inventory. Doors must be built between two existing structures, e.g. between two walls or fences.
A bug in 3.11c, (confirmed in 3.13p4), allows doors to remove large rocks. By surrounding the rock with fences, then building and deconstructing a door on the rock tile, it disappears.
Doors can be [o]pened and [c]losed with their respective commands.
Doors must be closed before they can be deconstructed.