Planning & Permissions
Do you need planning permission for a conservatory?
The general position, and why an extension is worth considering too.
Many conservatories fall under the same permitted development rules as single-storey extensions, subject to the same depth, height and position limits. Homespace Improvements doesn't build conservatories specifically, but the same rules — and often a better long-term result — apply to a single-storey rear extension.
Last updated 17 August 2026
The general permitted development position
A conservatory is treated as a single-storey extension for permitted development purposes, subject to the same depth and height limits that apply to any other single-storey rear or side extension — generally up to 4m for a detached house or 3m for other house types, before needing a planning application or the Larger Home Extension route.
The same exceptions apply too: flats don't have permitted development rights, listed buildings need full permission, and Article 4 directions can remove the rights on specific streets.
Why we'd usually point you toward an extension instead
A conservatory and a fully-built single-storey extension are governed by broadly the same planning rules, but they perform very differently — a conservatory's largely-glazed construction typically struggles more with year-round temperature control than a properly insulated extension built to current Building Regulations standards.
If what you're actually after is a genuinely useful, comfortable extra room rather than a specific conservatory aesthetic, it's worth weighing up a standard extension against the same planning backdrop.
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