Floor area of the room
Approved Document O: Overheating, published by HM Government in 2021, defines floor area of the room as: ‘The area of the room, measured to the internal face of the perimeter walls. Where a room serves more than one activity, e.g. open-plan kitchen and living room, the area with the largest glazing area should be assessed and the room area calculated based on a room depth no greater than 4.5m from the glazed façade.’
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