The sentence that causes the most expensive surprise is “we don’t need planning, so we can start on Monday.” GOV.UK is explicit: building-regulations approval is different from planning permission, and you might need both. This page is the building-control half. For what an extension usually costs per square metre, use extension costs.
GOV.UK also says you do not need to get approval yourself if you use someone registered with a competent person scheme for that work. That is a route, not a waiver you invent on site.
Building control is not the planning department
Planning asks whether the volume, the face of the house or the use is acceptable. Building control asks whether structure, fire, moisture, drainage, ventilation, electrics and heat loss meet the regulations. A rear extension that sits inside permitted development can still need full plans or a building notice. A boiler swap may need no planning and still need a competent-person notification.
Scotland and Northern Ireland run their own systems. Glasgow and Edinburgh lists on this site are phone numbers, not a warrant. Read the Scottish building-standards pages for those addresses.
Jobs GOV.UK lists as often needing approval
The GOV.UK “when you need approval” page includes constructing or extending buildings, and many alterations. Examples on that page include replacing fuse boxes and connected electrics, installing a bathroom that involves plumbing, changing electrics near a bath or shower, putting in fixed air-conditioning, replacing windows and doors, replacing roof coverings on pitched and flat roofs, installing or replacing a heating system, and adding extra radiators.
The same page says you could need approval for works not listed, and to check with a building-control body if you cannot decide. Emergency boiler repairs have their own “no advance approval, but rules you must follow” note on that page. Do not stretch that note over an extension.
- A habitable extension or loft conversion — almost always building control.
- A new covering on a roof, not a like-for-like slipped tile — often approval.
- A heating-system replacement — competent person or building control.
- A new bathroom that moves plumbing — often approval.
- Knocking through a load-bearing wall — structure, not “just an opening”.
The conservatory exemption is narrower than the sales brochure
Schedule 2, Class 7 of the Building Regulations 2010 describes a narrow exemption for some ground-level conservatories, porches, covered ways and open carports under 30m². Government circular advice adds conditions that building-control bodies still use: thermal separation from the house must stay in place, and the house heating system must not be extended into the space. Glazing still has to meet the relevant safety parts. Electrics taken from the house still have to meet Part P. Hot and cold water taken from the house still have to meet Part G.
Heat the conservatory from the house boiler, or take out the separating doors, and the exemption is the first thing you lose. That is a building-control judgement on the facts, not a discount this site can grant.
How approval is obtained
For work that is not a higher-risk building, GOV.UK says you may need approval from a building-control body: your local authority or a private registered building-control approver. Higher-risk buildings (at least 7 storeys or 18 metres, with the residential tests GOV.UK lists) go to the Building Safety Regulator. Ordinary houses on this directory are not that regime.
GOV.UK notes that from 1 October 2026, some residential building-control applications and initial notices may be subject to a Building Safety Levy. Check the live page for whether your application type is in scope. A levy is not a builder’s day rate.
GOV.UK says the person doing the work could be prosecuted and fined if they do not comply, and that you may lack the certificates a conveyancer will ask for when you sell. “We’ll sort the paperwork later” is how that starts.
What to have on the call
Have a simple description of the work, whether a wall is load-bearing, and whether anyone has already said the job is permitted development. Ask who will give notice to building control, whose name is on the completion certificate, and whether any part of the job will be signed off through a competent person scheme instead. For a number, open builders in London, Manchester or Leeds.
This site does not file an application and does not email the builder.
Questions before you treat “no planning” as “no paperwork”
Do I need building regulations if I do not need planning?
Often yes. GOV.UK says the two are different and you might need both. Most habitable extensions still need building-control approval.
Is a conservatory always exempt?
No. The Class 7 exemption is limited by size, thermal separation and not extending the house heating system. Building control decides on the facts.
Who applies?
You can apply, or a builder or designer can apply, or a competent-person installer can self-certify the part of the work their scheme covers. Ask whose name will be on the certificate.
Where do I find a builder?
Open a building city list and use the phone number on the profile. This site does not send your job or file a notice.
Need a builder’s number?
Open building and conversions and contact the business yourself. Building-control applications stay with you, the builder or a building-control body.