Casement windows are the most popular window style in the UK today. Around 80% of British homes account for this type of window. The name casement refers to the opening part of the window and originates from when windows used to be fixed and opening sashes were just introduced. Casement windows are typically hinged at either the side or the top and the sashes normally open outwards. An inward opening casement window is also available and is commonly known as a tilt and turn window. Top opening windows are often referred to as awning windows.