House



A Home (or House) is a structure built by the player that can serve as a spawn point for NPCs. NPCs require an unoccupied Home before they can appear (with the exception of the Guide and Travelling Merchant).

The Goblin Tinkerer, Mechanic and Wizard will each make their initial appearances regardless of available Homes. Once initially found, each will require a Home in order to respawn subsequently.

You can check if a Home's construction is suitable with the Housing Menu.

Requirements
A structure of home must meet numerous requirements in order for the game to recognize it as a proper home suitable for spawning NPCs.

Size
Including the floor, side walls and ceiling, a Home must have at least 30 total tiles but less than 750.

The minimum rectangular regions which count as a Home are:

Framework


A house must be fully enclosed:


 * The side walls (vertical blocks) can be made of blocks, doors or wood platforms.
 * The floor and ceiling (horizontal blocks) can be made of blocks or wood platforms.
 * The NPC needs at least one solid (non-platform) block to stand on at night. This block may not be directly adjacent to either of the walls of the house.

Empty floor space
A House requires at least four tiles of empty floor space.


 * Furniture must be placed so that at least four tiles of space exists that is clear of any furniture or blocks. This includes the Comfort and Flat Surface items (see below), which in a minimum-sized house must be placed off-center in order to make the House suitable. This space can be left between two furniture items, or between an item and the House's framework wall.
 * Some decorative items do not affect this requirement, such as Statues, which can be placed in the empty area without invalidating the house.
 * One of these empty floor tiles must be a solid (non-platform) block, which the NPC needs in order to stand at night. I love animals.

Entrance
A house must have at least one entrance, which can be a door in a wall or a wood platform in the ceiling, floor, or walls. There was a bug that when a door was opened inwards, the housing would no longer be considered a suitable housing, however this was patched in the 1.2 Update

Background Wall


A house must have a background wall in order to be suitable. Any walls crafted or mined by the player are valid, when placed.


 * Walls not placed by a player (such as naturally-occurring dirt walls) do not count, with the exception of those generated in Floating Island structures, the planked walls found in Underground Cabins, or the living wood walls in Living Tree rooms.
 * Background walls may contain holes if the holes are no taller or wider than four tiles. (e.g. 4 background tiles across or tall, so the maximum size is 4x4, 16 in total. The hole cannot exceed 4x4 or 16 tiles.).
 * Walls may have multiple holes as long as they are separated by at least a single tile of background walls.
 * Having background holes will sometimes allow monsters to spawn within the Home.

Furniture
A Home must have at least one Comfort item and one Flat Surface item.

Comfort items
At least one Comfort item must be placed in a Home. Currently the following items may function as Comfort items:


 * (any)

Flat Surface items
At least one Flat Surface item must be placed in a Home. Currently the following items may function as Flat Surface items:
 * (any)
 * (any)
 * (any)
 * (any)
 * (any)
 * (any)

Light Source
A Home must have at least one light source. A Furnace, Lamp Post, Disco Ball, Campfire, Glowstick and lava will not work for this purpose. Currently the following items may function as a Light Source:
 * (any)
 * (any)
 * Blue Light.png Red Light.png Green Light.png Christmas lights
 * (any)
 * Blue Light.png Red Light.png Green Light.png Christmas lights
 * (any)
 * Blue Light.png Red Light.png Green Light.png Christmas lights
 * (any)
 * Blue Light.png Red Light.png Green Light.png Christmas lights
 * (any)
 * (any)

Location
If a Home is located near Corruption (or Crimson), it may become uninhabitable. A Home is corrupted based on its "Corruption Rating," which calculates all tiles in a 45-block "radius" around the house; a house's Corruption Rating must be 250 or less. This is about half the blocks in the radius. Each block of ebonstone, ebonsand and corrupted vines & plants increases a Home's Corruption Rating by 1. Conversely, each sunflower reduces a Home's Corruption Rating by 5; and each block of hallowed grass, pearlsand and hallowed plants reduces the rating by 1.

Simplest valid option
Materials required:
 * 25 Dirt Block for floor, wall and ceiling.
 * 32 Dirt Wall (8 Dirt Block) for background wall.
 * Wooden Door (6 Wood). Can be replaced with one Wood Platform.
 * Wooden Chair (4 Wood).
 * Wooden Table (8 Wood).
 * Torch (1 Wood, 1 Gel, results 3).

Summary raw materials:
 * 33 Dirt Block
 * 18 Wood (if using door) or 13 Wood (if using a single wood platform)
 * 1 Gel

This works, but if you don't want house to be occupied by vines it's recommended to replace dirt by wood, stone or mud, or just clear the walls from grass. While this is the simplest option, it's very susceptible to corruption.

Wood might be considered simpler than dirt for wall, ceiling, and background wall, since many pieces are acquired from cutting down a single tree.