Housing is a cluster of buildings which provides housing for a Population of up to 70. Two Housing units and an accompanying Food Market housing module are pre-built for the player upon arrival to the island. As a result, Housing is one of few buildings which does not require any research.
When building additional sets of Housing, they will attempt to automatically "snap" to each other (as indicated by a lime green border during placement). Housing placed adjacent in this manner can then share the use of any housing modules. In that case of this basic variant of Housing, the only module typically utilized is the previously mentioned Food Market.
Each tier of housing provides double the capacity as the previous tier. In exchange, higher tier housing also increases the utility demands across the island. If these needs are met by way of the additional and connection of the appropriate housing module, a boost is given to the Unity growth rate. There is no penalty for not providing these modules or failing to meeting the increased demands.
If Housing buildings are not "snapped" to each other so they are perfectly adjacent along the length of any one side, each will be considered its own Settlement. Both will still be able to independently of each other, but without the ability to share housing modules.