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Q&As
Can I turn an outbuilding into a residential space?
I’m in process of building a large cinema room/workshop in my back garden. The project has been granted full planning permission. There is access to the new outbuilding via a side gate. So, I'm wondering if I can change its use to self-contained residential, with its own mortgage separate from my house?
One Answer
Hi Colette,
Thanks so much for your question. Although you already have planning permission for your outbuilding, you would need a new planning permission to convert it into an entirely separate dwelling.
This is because the council will want to assess some of the planning issues that can arise with a new home – whether it is large enough, has enough rear garden space, has sufficient parking and whether it causes any harm to neighbours in terms of overlooking, for example.
Local planners can be quite hostile to new houses in the gardens of existing properties – they can look out of place, and if the main home and the outbuilding are occupied by different families, there can be problems with noise and disturbance.
Rather than creating a fully separate dwelling, you should consider making it a residential annexe. As an annexe, the space would not be eligible to be occupied by anyone outside of your own family/ household. It could be utilised by those such as elderly parents or a teenager who needs their own space. You do not usually need planning permission to convert an existing outbuilding into a residential annexe, but it’s best to double check with your local authority.
Best of luck with your project,
Martin Gaine (Build It’s Planning expert)