ePrivacy and GPDR Cookie Consent by Cookie Consent Full planning, lawful development & prior approval: A guide

Explained: full planning, lawful development, and prior approval

5 min read
Oct '25 • by Heather

Quick summary

In the UK, most projects like extensions or conversions can be done under permitted development rights, which don’t need planning permission, but they are subject to strict rules on size, height, and impact, with some property types excluded. If your project needs extra storeys or larger extensions, you’ll likely need prior approval or full planning permission, which can take around 8 weeks and cost between £85 and £206, depending on location.

Whether you’re extending or converting, there’s one word that hangs heavy over any residential project: planning.

If you’ve never navigated UK planning policies before, the prospect can be daunting. What approval do you need? What can you accomplish without it? If these questions have you scratching your head (especially in light of the 2020 planning changes), don’t worry!

With our own team of planning agents and experts, we’ve put together this handy guide…

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