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Q&As
Can I add an extension to a house in the Green Belt that has already been enlarged?
I recently bought a small bungalow in the Green Belt that sits on a very large plot. The previous owner already extended the house quite a lot, but we have a large family and would like to make it much bigger. Our nearest neighbours are far away and the plot is spacious, so it seems like there should be plenty of room to extend. However, the council says we can’t add any more extensions because the house has already been enlarged. Is that right?
One Answer
This is quite a common situation in the Green Belt. Planning rules in these areas are particularly strict and people are often surprised to find that they apply not only to new houses but also to extensions of existing ones.
National planning policy states that home extensions in the Green Belt are unacceptable if they result in a “disproportionate” increase in size compared with the original building. Councils usually assess this by comparing the house’s current size with its size when it was first built.
If a previous owner has already doubled the size of the property through extensions, the council will likely conclude that the house has already reached – or exceeded – the acceptable limit for enlargement. In those circumstances, even small additional extensions will usually be refused be refused.
This is very frustrating for homeowners, especially where the plot is large and neighbours are far away, but Green Belt policy is applied very strictly and, when it comes to extensions, is mostly about the cumulative percentage increase in the size of the house.