What is planning permission?
A planning application asks the local planning authority to assess a proposal against relevant planning considerations. The information required depends on the nature and location of the project.
What is permitted development?
Permitted development rights allow certain categories of development without a conventional planning application, provided all relevant limitations and conditions are satisfied.
Why the distinction matters to design
Designing directly to a permitted-development envelope can make sense for some projects. In others, a planning application may allow a better solution. The route should follow the project objectives and constraints rather than becoming the design objective itself.
Neither route replaces technical approval
Planning and Building Regulations deal with different matters. A project that is acceptable in planning terms still needs appropriate technical design and regulatory compliance before construction.
General guidance only. Planning, Building Regulations and project requirements vary by property and circumstances; project-specific advice should be obtained before relying on a particular route.