The word Maisonette has been derived from the French word which means a small house. The modern maisonette is however a large multi-storey apartment which is usually located in a big apartment building. The buildings may be connected with each other via an internal staircase. This is mainly done in the old buildings which are connected with the new buildings. The top floor is connected with the attic for the buildings in which attic conversion takes place. Pre-planned extensions of the roof of the flat for the new buildings are also done in maisonettes. The usual layout of the apartment is combined with a few other features. Combined dining room with kitchen, living space on the lower floor and the bedrooms and a bathroom on the second storey are the modifications usually made in the design.
These kind of buildings developed in the United Kingdom with the rise of the middle class in the country. More space was required and they needed to stay in London for the development of trade and other businesses. Hence maisonettes began to be developed so as to accommodate more people in a single building in the city of London.