Building Regulations vs Planning Permission: the UK distinction homeowners confuse

The most expensive sentence in UK home improvement is "the council said it's fine" — because there are two councils-that-say, and they answer different questions. Planning permission asks whether you may build it at all: land use, size, appearance, neighbours, the street. Building Regulations ask whether it's built properly: structure, fire, ventilation, energy, electrics, drainage. A project can need neither, either, or both — and assuming one answer covers both questions is the confusion this page exists to fix.

Planning permission: the whether-and-where

Decided by your local planning authority, planning concerns the principle of development: is a new building or extension allowed here, how big, what it looks like, what it's used for. Much ordinary home improvement falls under permitted development — rights to build certain limits of extension, loft conversion or outbuilding without a planning application — with the rules tightening for listed buildings, conservation areas and homes that have already used their allowances. What planning does not do is check a single technical detail of construction.

Building Regulations: the how

Building Regs apply to most "building work" — the legal definition (Regulation 3) reaches further than people expect: extensions, structural alterations (removing a wall), most window and door replacements (through FENSA/CERTASS-style certification), new or rewired electrics (Part P — its own guide), new boilers and heating work, bathrooms moved or newly created, drainage. Compliance is checked by building control — your council's team or a private approved inspector — with inspections at stages and a completion certificate at the end. Cosmetic work — paint, wallpaper, like-for-like kitchen units, floor coverings — sits outside both systems.

The four combinations, with examples

Both: a large extension beyond permitted-development limits — planning for size and appearance, Building Regs for construction. Building Regs only: the classic — a rear extension within permitted development needs no planning application and still needs full Building Regs approval; so do a structural wall removal (no planning at all, and the completion certificate is essential) and most electrical work. Planning only: rare for householders, mostly land-use changes. Neither: decoration and like-for-like repairs. The everyday trap is the second row: the homeowner who checked planning, found permitted development, and never heard of building control until a buyer's solicitor asked for the certificate a decade later (that conversation has its own guide).

Why the distinction bites

The enforcement teeth differ: unauthorised planning breaches face enforcement notices with time limits; non-compliant Building Regs work is enforceable through the courts as a criminal matter, with powers to require work to be opened up or fixed — and either way, the missing paperwork is found by every surveyor, solicitor and lender a property passes through. The healthy habit is two parallel checklists for any project beyond decoration: do I need planning (or am I within permitted development)? and does this is building work that needs Building Regs sign-off — and which parts need a registered installer? Your council's planning and building control teams answer the first and second respectively — asking each team its own question is half the battle.

Sources: GOV.UK planning portal and Building Regulations guidance; local-authority building control explanations (Regulation 3 "building work"); Approved Document P for electrical notification. Reviewed September 2026 · general information, not legal advice — permitted-development limits and guidance differ across England, Scotland, Wales and NI.