This is a proposed garden building in quite a large garden, tucked away in the corner however, it is tall and located reasonably close to the garden boundaries and so has therefore raised objections from neighbours and the Parish Council.
The refusal does include intensification of use, but if this is purely a family annex, we would suggest approaching the planners with a proposed structure that complies with the requirements of Class E of the Permitted Development Order, which in certain circumstances allows up to 50% of the garden to be covered in a building of not more than 4m tall for incidental use to the dwelling, i.e. a swimming pool! These discussions should bring forward an acceptable option to re-submit, and with a stronger case, go to appeal if there is a subsequent refusal.