Building regulations vs planning permission, briefly

Two separate systems, two separate approvals, and mixing them up costs real money on real jobs. Here is the working distinction every builder should be able to explain to a client in under a minute, in general terms, with the specifics always confirmed with the local authority.

Two systems, two different questions

The confusion exists because both systems involve the council, both involve drawings, and both can say no. But they are asking entirely different questions:

• Planning permission asks: should this thing exist here? It is about what the development looks like, how big it is, where it sits, and how it affects neighbours and the area.
• Building regulations ask: is this thing built safely and properly? They cover the technical standards of the work itself: structure, fire safety, insulation, ventilation, drainage, electrics and more.

The point that catches people out: they are independent. A project can need one, both, or in some cases neither. Having planning permission says nothing about building regs, and vice versa. A builder who can explain that clearly at the first meeting sounds like a professional, because they are being one.

Planning permission in one paragraph

Planning is about the development as a whole. Extensions, outbuildings, loft conversions with dormers, changes of use: whether these need a planning application generally depends on their size, height, position and the property's history and location. Many domestic projects fall under what is known as permitted development, which allows certain work within set limits without a full application, but those limits have real teeth and are affected by things like conservation areas, listed status, flats versus houses, and whether previous owners already used up the allowance. The only safe habit is to treat "it should be permitted development" as a question for the local planning authority, not an answer, and many homeowners choose to get a lawful development certificate for peace of mind.

Building regulations in one paragraph

Building regs are about how the work is done, and they apply to far more projects than planning does. Structural alterations, extensions, loft conversions, new drainage, most replacement windows, many electrical and heating jobs: all generally fall within scope, even when no planning permission is needed at all. Compliance is checked by building control, either the local authority's team or a registered private inspector, through plans and site inspections, ending in a completion certificate. That certificate matters beyond the job itself: solicitors ask for it when the house is sold, and missing certificates have a way of surfacing at the worst possible moment.

What this means at quote stage

For builders, the practical questions land in the pricing conversation, well before anyone digs:

• Ask early what approvals exist. "Do you have planning permission and building regs approval?" belongs in the first conversation, alongside the rest of the questions to ask before pricing anything.
• Price the compliance costs visibly: building control fees, structural engineer's calculations, any certification for electrics and gas. Hidden compliance costs become arguments, priced ones become professionalism.
• State in the quote whose job the approvals are. "Client to obtain planning permission; building control application by contractor" is one line that prevents a very expensive misunderstanding.
• Never start notifiable work on a nod. If the drawings are still "with the architect", the quote can be ready, but the start date cannot.

Where these items live in the document is covered in what a professional builder's quote should include.

There is a commercial angle too. Homeowners are nervous about this exact subject, because they have all heard the story of the extension that had to be altered after the fact. The builder who raises approvals unprompted, explains the difference in a minute and knows who to call is not adding friction to the sale, they are removing the client's biggest silent fear. On jobs where two quotes are otherwise close, that conversation is often the thing that decides it.

Always confirm the specifics

Everything above is general background, not legal advice, and the detail genuinely varies: by nation within the UK, by property type, by conservation status, and by what previous owners did to the house in 1987. The rules also change over time. For any specific project, the answers come from the local planning authority, building control or a suitably qualified professional, in writing, before the work is priced as final. Builders who make that phone call early look slower for a day and smarter for a decade. And where a shared wall with the neighbours is involved, there is a third system to know about entirely, covered in party wall basics every extension builder should know.

When the approvals picture is clear, the pricing should be just as clear. QS Quoter builds itemised quotes from a description or drawings at your own rates, with room for the compliance lines that separate professional quotes from hopeful ones.