The Door is a simple opening and closing mechanism in Terraria’s sandbox. It is a basic building structure that is used in almost every building ranging from houses to dungeons. Compared to a regular block, the placement of a Door in Terraria can be a bit tricky to get used to.
This is mainly due to the placement prerequisites that are needed to be fulfilled in order to place a successful door. Therefore, the main reason you can’t place a door in Terraria is due to obstructions being present in its building path.
A door won’t open, let alone be placed if it is blocked by some other placeable Terraria block. It needs a 3 x 1 space in order to be placed. However, there are times when even this won’t be enough. Placing these doors is the basic requirement to build a house in order to call in NPCs.
How to Place a Door in Terraria
In order to place a Door, you will need an available building space of 3 x 1 blocks. There also needs to be a block just above the placing location of the Door. In simpler terms, there should be a block in both the vertical top and bottom so the door can be placed in the 3-block vertical empty space in between. The placed door can then be right-clicked to open and close.
You also need to make sure that the blocks you are working with are solid and whole. This means that the placed blocks shouldn’t be half-mined. If you feel like the block is to blame for this issue then by all means, consider changing it. Mining it and placing it again should also do the trick if you run out of blocks.
How to Use Doors Properly
Doors open left or right in Terraria. However, they can be stopped from opening in a certain direction by having obstacles placed in their opening direction. Generally, it is advisable to not have anything (excluding background walls) in a 3 x 1 radius of a door in both directions.
This includes putting platforms or furniture as well so make sure to have the coast clear. Another key thing to note is that the enemies can open doors in the Blood Moon event. Thus, you should not consider a door to protect you against enemies. Doors can be opened automatically when a player approaches them so they are not that hard to use.
All in all, placing a door is a basic mechanic of the game and should not take much time to get used to. There are several kinds of craftable doors present in Terraria. There are also some non-craftable ones that have high collectible value. The general purpose of the door remains the same no matter what you place.