Belfast·SPG004 Residential Extensions and Alterations·Page 25·RD2
Permitted Development for Rear Extensions
Rear extensions to dwellings, including single and two storey extensions, may be permitted development if they comply with dimensional and boundary proximity requirements. Conservatories attached to a house are treated as extensions for this purpose.
What is allowed without planning permission applies largely to the dimensions of the proposed extension and its proximity to plot boundaries. A conservatory attached to the house will be treated as an extension.
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