Do you need planning permission?
This article is about the Planning Permission required or not? for the Loft Conversions.
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Planning permission is not normally required. However, permission is required where you extend or alter the roof space and it exceeds specified limits and conditions.
These are specific to "the enlargement of a dwellinghouse consisting of an addition or alteration to its roof" as detailed in Schedule 2, Part 1, Class B of the The Town and Country Planning (General Permitted Development) (England) Order 2015.
A loft conversion for your house is considered to be permitted development, not requiring an application for planning permission, subject to the following limits and conditions: