Planning permission or Building Regulations, what's the difference?

You've been told you need planning permission. Or you've been told you don't. And now somebody has mentioned Building Regulations and you're not sure whether that's the same thing said a different way, or whether it's another hoop entirely that nobody had bothered to warn you about.

They're two completely separate approvals. Different departments, different rules, different drawings, different fees, and you can very easily need one without needing the other. Getting them mixed up is one of the more expensive mistakes we see people make, because somebody who's been told quite correctly that they don't need planning permission then reasonably assumes there's nothing standing between them and a builder. There is. There's usually rather a lot standing between them and a builder, and it's the approval that actually governs how the thing gets built.

If you're not yet sure which of them applies to your project, whether you need planning permission at all is the place to start.

Planning is about the outside, and about everybody else.

What the council is really asking is whether this thing should exist here at all, and their concerns run along fairly predictable lines. How big is it, where does it sit, does it overlook the neighbours, does it take their light, does it fit with the rest of the street, is there still somewhere to park a car, does it match the policies in the local plan and the previous decisions the council has made on similar sites nearby. That's the whole territory. Nobody in a planning department is remotely interested in how deep your foundations are or what your insulation values look like, because none of that affects anybody outside your boundary.

The department dealing with it is the local planning authority, which around here means Amber Valley Borough Council, Derby City Council, Nottingham City Council, and a handful of others depending on exactly where you are.

Building Regulations are about whether the thing is safe and properly built, and whoever reads your Building Regulations drawings genuinely does not care what the extension looks like from the pavement.

What they care about is the foundations and whether they're deep enough for the ground you're building on. The structure holding it all up and whether the beams are the right size. Whether the insulation meets current standards. Fire safety, and specifically how somebody gets out of the building if the worst happens. Drainage, above ground and below it. Ventilation, damp proofing, staircase pitch and headroom, the glass in the doors, and the electrics.

The department is Building Control, and you have a choice here that surprises people. You can use the council's own Building Control team or you can appoint a private approved inspector. Both are entirely legitimate, both work to the same national regulations, and there's no advantage in planning terms either way. We work with both and we'll talk you through which suits your particular project.

This is the part worth getting straight, because the combinations aren't obvious.

Building Regulations approval with no planning permission is far and away the most common position we deal with. Most loft conversions fall here. So does taking out a load bearing wall, and a garage conversion, and any extension built comfortably within Permitted Development. All of those need Building Regulations approval, and none of them needs a planning application at all.

Planning permission with no Building Regulations is rarer but it does happen. A large detached outbuilding that isn't habitable. Certain fences, walls and gates. A change of use where you aren't actually altering the fabric of the building.

Both approvals together covers most extensions of any real size, new houses, and anything structural that's also visible from outside.

And neither applies to genuinely minor work. Redecorating, replacing something like for like, small non structural projects.

The combination to watch is the first one, and it comes up constantly. Somebody rings us delighted that their loft conversion doesn't need planning permission, and they've already got a builder in and joists going down. They were right about the planning. They were badly wrong about the rest of it, and now there's a staircase in at a pitch that won't pass, no fire door at the bottom, and insulation that doesn't come close to Part L, all of which has to come out again and go back in properly at their expense.

Building Regulations are set out in a series of Approved Documents, and each one deals with a single subject and gets a letter. Part A is structure. Part B is fire safety. Part C covers site preparation and resistance to moisture, which is your damp proofing and, in some parts of Derbyshire, your radon protection. Part K is protection from falling, collision and impact, which is where staircases and balustrades live. Part L is conservation of fuel and power, meaning insulation and heat loss, and it's the one that's tightened most over the years. Part M is access. Part P is electrical safety.

You don't need to know any of that, it's our job. But if your Building Control officer starts talking about Part B or Part L on a site visit, at least you'll know roughly what territory you're in.

There are two ways to get Building Regulations approval and the difference between them matters more than most people realise.

Full plans means we submit detailed drawings and structural calculations, and Building Control check the whole lot and approve it before anything gets built. You get an approval notice in writing. If there's a problem with the design, you find out about it on paper at a desk, which is by far the cheapest place to find out about a problem.

Building notice means you simply give notice that you're starting, and the work gets inspected as it goes along. It's quicker to get moving because there's nothing to wait for, but there are no approved drawings, and if the inspector turns up and doesn't like what he sees then it comes out and gets done again at your cost, with your builder standing there while you have the conversation.

For anything structural we'd recommend full plans every single time, and we'd say that even where the building notice route is technically available. It's the version where you know exactly where you stand before a brick is laid, and it's also the version your builder can actually price properly, because he's pricing from a real specification rather than guessing at what he might be asked to do in eight weeks' time.

Building Control have five weeks to decide a full plans application, or eight if you agree to an extension, and that's a good deal quicker than planning. It normally runs after the planning application or alongside it rather than before it.

The approval itself lasts three years, same as planning permission.

When the work's finished and the final inspection has been done, Building Control issue a completion certificate. That's the document proving the work was inspected and signed off properly, and it's the whole point of the exercise as far as your future self is concerned.

You want it. When you come to sell, the buyer's solicitor will ask for it on any extension, loft conversion or structural alteration, because it's a standard enquiry on every conveyance. Not having one holds sales up and it knocks money off asking prices, and we have watched people discover this fifteen years after the event with no easy way of putting it right.

There is a route if work was done without approval, called a regularisation application, where Building Control assess what's already there and certify it retrospectively. It genuinely does work and we've done a fair few. It also sometimes involves opening up finished work so the inspector can see what's underneath the plaster and the floor, which is exactly as painful and as expensive as it sounds, and considerably worse if the answer turns out to be that the beam is undersized.

Usually a measured survey first, then planning if it's needed, then Building Regulations drawings, and then your builder prices from those.

Sometimes they overlap. If a project is clearly covered by Permitted Development we'll skip straight to Building Regulations drawings and save you the wait entirely, and on larger schemes we'll often get the Building Regulations work moving while the planning application is still sitting with the council, because there's no sense in doing them one after another when they can run side by side.

We'll tell you the right order for your particular project at the first visit, and that visit is free with no obligation at the end of it.

If you want the detail on the planning side there's more in how to get planning permission, and for the technical drawings themselves have a look at Building Regulation drawings.

For more information please call us on 07773 899 597 or contact us through this website.