Some blocks have tiers when used to construct a room. The tiers of the blocks used to construct a room determine the room's overall tier level, which affects what crafting stations can operate in it: for instance, the Anvil requires an overrall room tier of 1 before it will function. The overall tier of a room also determines the maximum skill points that can be gained from furniture placed in it.
(and other natural blocks, such as Iron Ore, Copper Ore, and Gold Ore)
|Hewn Log Door||1|
|Large Lumber Door||2|
|Large Windowed Lumber Door||2|
|Large Corrugated Steel Door||3|
|Framed Glass Door||4|