Door
From UnReal World Wiki
Doors can be constructed through the Wooden Building submenu within the Building menu (Alt + b). They allow the player and NPCs to enter a building without having to leave one wall unconstructed. They can be made from 8 boards and must be built between two existing structures, e.g. between two walls or fences.
Doors can be [o]pened and [c]losed with their respective commands.
Doors must be closed before they can be deconstructed.
A bug (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. This bug is still active as of version 3.32.