A permission with conditions, not an exemption from planning
The General Permitted Development Order sets out development classes and the requirements attached to them. A proposal must fit an available class and satisfy its restrictions. Being small, being at the back of a house or resembling work nearby is not a substitute for that test. [1][3]
There is also a separate possibility: some work is not development for planning purposes in the first place. Internal work which does not materially affect a building's external appearance is one example identified in government guidance. “Not development” and “permitted development” are different legal explanations, even when neither requires an ordinary planning application. [2]
Rights depend on the property and the particular work
The familiar householder rights cover different types of projects, including extensions, roof alterations, porches and outbuildings. Each has its own conditions. A limit applying to a garden building is not automatically the limit for an attached extension. [4]
Check the following before using a published allowance:
- Whether the property and its authorised use qualify, including any restriction arising from its conversion history.
- Whether a planning condition or Article 4 direction removes the relevant right.
- Whether the location has additional restrictions, such as those applying on designated land.
- Whether existing additions affect the calculation for the new proposal. [3][4][1]
The right is not a fresh allowance for every successive owner. The “original house” baseline and the treatment of earlier enlargements remain relevant when a property changes hands. [4]
Some permitted development still needs an application
Prior approval is required for some classes. The council checks the matters specified for that particular right, which may include neighbouring amenity or external appearance. The procedure, information and start restrictions differ between classes. [5][2]
Other projects can proceed without prior approval if they meet all applicable requirements. A proposed Lawful Development Certificate is a separate, optional way of obtaining a formal determination of planning lawfulness. It does not excuse an omitted prior-approval application. [6][2]
For a homeowner, the useful question is therefore not just “Is this permitted development?” but “Which class applies, what does it require, and which documents establish that those requirements are met?”
Use the rules in force, not a proposal
Government consulted on wider changes to householder rights in February 2024. A consultation document is not an operative permission. Check any claimed new allowance against the legislation and its commencement provisions before changing the design. [7][1]
Keep the construction checks
Permitted development does not approve structural design or replace building regulations approval. Nor does it resolve the Party Wall Act process. Establish those requirements separately and keep the planning evidence with the project records. [8][9]