Specific Councils may have different rules - but in general you can buildg an extension to the rear of the house which does not increase the original floor area of the house by more than 40 square metres and is not higher than the house. The extension should not reduce the open space at the back of the house to less than 25 square metres
Building a garage at the back or side of a house so long as it does not extend out in front of the building line of the house and does not exceed four metres in height (if it has a tiled/slated pitched roof) or three metres (if it has any other roof type). This building will be exempt from planning permission once the floor area is limited to 25 square metres. Garages or sheds to the side of the house must match the finish of the house and may not be lived in, used for commercial purposes or for keeping pigs, poultry, pigeons, ponies or horses.
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