A house addition is an extra structure or feature that can be added to a home. An ANNEX is a separate building, usually connected to the main house, that can be used for additional living space. An ELL is an extension of the main house, usually in the form of a wing. A DECK is an outdoor platform, usually made of wood, that is attached to the house and can be used for entertaining or relaxing. A breezeway is a covered walkway connecting two buildings, such as a house and a garage.