Many people think that bay windows add interest to a house and they were certainly popular during the house building booms of the 1930s and 1950s. A bay window is an area which protrudes outwards from the main body of a house and forms a bay inside a room.
When a bay is curved it is called a bow window. Many bay windows are polygonal (often with 5 panels of windows) or square or rectangular. A bay window which is supported by a bracket or a corbel is known as an oriel window. Oriel windows are often found projecting from an upstairs room, usually the small bedroom at the front of a house. Sometimes a bay window will only be found on the ground level of a house – this was a popular design for Victorian terraces – with the top of the bay having a small flat roof area or a few rows of roof tiles. However, for most 1930s and 1950s suburban semi-detached houses, the bay window encompasses both the ground floor and the first floor.
The advantage of building a house with a bay window is that it can increase the amount of natural light which comes into a room and it provides the occupants of the house with different aspects of view, more than a flat window could provide.