TL;DR: For a straightforward domestic job in England, a building notice gets you on site quickly but no plans are checked, so the risk of non-compliant work sits with you until each inspection. A full plans application should be decided within five weeks, or longer if you agree in writing, and in return you get plans passed against the Building Regulations before you build. Some work cannot go on a building notice at all, and if you would rather not use the council, a registered building control approver (RBCA) is a third route.
Choosing between a building notice and full plans is one of the first decisions on any job that needs Building Regulations approval, and building notice vs full plans is not just a paperwork question. It decides when you can start, what the council checks before you dig, and who pays if building control finds a problem halfway through. This guide covers England only. Wales has its own Approved Documents and procedures, Scotland uses the Technical Handbooks and building warrants, and Northern Ireland uses the Technical Booklets. None of what follows should be read across to those three.
One point before anything else: Building Regulations approval and planning permission are two separate regimes. A rear extension can be permitted development under planning and still need Building Regulations approval. A change of use can need planning permission and Building Regulations approval at once. Neither application covers the other. If you need the background on how the Regulations and the Approved Documents fit together, start with our guide to UK Building Regulations and the Approved Documents explained.
What are the two local authority routes to Building Regulations approval?
The law is the Building Regulations 2010 (SI 2010/2214), made under the Building Act 1984. When you use your local authority building control team, there are two ways to tell them about notifiable work.
A full plans application. Since the 2023 amendments in England, the Regulations call it an "application for building control approval with full plans". You deposit drawings and supporting information showing how the work will comply with the requirements in Schedule 1. Building control checks the plans and either passes them, passes them with conditions, or rejects them.
A building notice. You tell the council the work is going ahead, with a description and location plan, and the work is checked through site inspections rather than an upfront plan check. The Regulations are explicit that a building notice, and any plans that go with it, is not to be treated as an application for building control approval with full plans. There is no plan approval to rely on.
Both routes still need the work to comply with the Regulations. A building notice does not lower the standard. It moves the checking from the drawing board to the site.
How does a full plans application work?
Under regulation 14A of the Building Regulations 2010, the local authority must give its decision within five weeks of receiving the application, or within a longer period if you both agree in writing. GOV.UK still quotes two months for that longer period, but the regulation itself sets no upper limit. Agreeing to the extension is often sensible on a more complex job: it gives building control time to raise queries and you time to amend the drawings, rather than having the plans rejected against the clock.
The council can:
- pass the plans, which is a formal approval of the design as submitted
- pass them with conditions, typically requiring a modification or asking for further plans (a structural calculation for a beam, say, before that element goes in), which in England the council can only do if you ask for it or agree in writing
- reject them, with the reasons stated
You do not have to wait for the decision before starting. Once you have given notice of intention to start work (see below), you can start work while the plans are still being checked. If you do, you carry the same risk as a building notice until the decision lands, so on anything structural it usually pays to wait.
What the decision gives you is protection. Under section 36 of the Building Act 1984, the local authority can serve notice requiring non-compliant work to be taken down or altered, and in England the Building Safety Act 2022 extended the time limit for that notice from 12 months to 10 years from 1 October 2023. Where the council has passed your plans and the work has been carried out in line with them, that power to require removal or alteration does not apply. For work in the ground and the main structure, that protection is the main reason to go full plans.
How does a building notice work?
A building notice is quicker to get in. There is no plan check and no decision to wait for. Once the notice is given, you give notice of intention to start work and you can start two days later.
That speed comes with conditions:
- Building control can still ask for plans. Under regulation 13, the local authority can specify in writing the plans it needs to carry out its functions, and you must provide them within the time it sets. On a job with a steel beam or an altered roof structure, expect to be asked for calculations.
- Every element is judged on site. The inspector sees the foundations, the drainage, the structure and the insulation as they go in. If the inspector says the trench is not deep enough, the beam is undersized or the insulation is the wrong thickness, you put it right at your cost, often after the work it sits under has been built.
- There is no approved design to point back to. If the client, the engineer and the inspector disagree about what is acceptable, you have no passed plans to settle it.
For small, well-understood domestic work, such as removing an internal wall with a standard lintel, a simple single-storey extension on good ground or a replacement bathroom with new drainage, the building notice route works well and is widely used. The risk grows with the size and complexity of the job.
When can a building notice not be used?
There are cases where the council will not accept a building notice and you must make a full plans application. Councils across England list these consistently:
- Buildings covered by the Regulatory Reform (Fire Safety) Order 2005. If the building, once the work is complete, is one the Fire Safety Order applies to, you need full plans. In practice that is almost anything other than a single private dwelling and its extensions and alterations: shops, offices, workshops and the common parts of blocks of flats.
- Building over or near a public sewer. Where requirement H4 of Schedule 1 (building over or near sewers and drains) applies to the work, you must deposit full plans. Many councils treat work within 3m of a public sewer as falling in this group, and the sewerage undertaker will usually need to be consulted as well.
- A new building fronting a private street. A private street is one that is not a highway maintained at public expense, typically an unadopted road. A new building fronting one needs full plans.
On top of those, higher-risk building work is outside this system altogether. Regulation 12 does not apply to it, so a building notice cannot be given for it. Work on a higher-risk building (at least 18m or 7 storeys, and containing at least 2 residential units, or a care home or hospital of that height) goes to the Building Safety Regulator, not to local building control. Most domestic builders will never touch this, but a refurbishment inside a qualifying block of flats can bring it into play.
If you are unsure whether your job falls into one of these groups, ask the building control team before you submit. A building notice the council cannot accept costs you time, not just a resubmission.
When can you start, and what notices do you have to give?
Whichever route you use, you must give the local authority notice before you start work. Regulation 16 requires at least two days' notice, counted from the end of the day the notice is given. Many councils put this as 48 hours on their forms. A Friday-afternoon notice does not mean you can break ground on Saturday morning.
The 2023 amendments added a second notice that a lot of the trade has missed. Under regulation 16(3C), you must also tell the council when the work has reached the point where it is "regarded as commenced" for regulation 46A, within five days of reaching that point. This is a separate notice from the notice before starting work, and the council can reject it within four weeks if it does not agree the work has reached that stage.
Regulation 46A defines what "commenced" means, and it is not the day the digger turns up:
- A building that is not complex, or a horizontal extension: commenced when the sub-surface structure, including all foundations, any basement level and the structure of the ground floor, is completed.
- A complex building: a separate test applies, tied to the foundations and lowest floor structure.
- Any other building work (a loft conversion, internal alterations, a change to an existing building that is not a horizontal extension): commenced when the part of the work the client states amounts to 15% of the proposed work is completed.
You can read the full definitions in regulation 46A of the Building Regulations 2010 on legislation.gov.uk.
At the other end, you give notice within five days of completing the work, and building control issues a completion certificate once it is satisfied the work complies. Keep it with the job file. The homeowner's solicitor will ask for it when the property is sold.
How long does a building notice or full plans approval stay valid?
Both routes lapse if work does not commence in time. For a full plans approval, "commence" now means the regulation 46A definition above, not just a start on site; the building notice rule in regulation 13 does not refer to regulation 46A, so ask the council how it will judge commencement on a building notice job.
- A building notice ceases to have effect three years from the date it was given to the local authority, unless the work has commenced before then.
- A full plans approval lapses automatically in England if the work has not commenced within three years of the day the application was made. Under the old rules the council had to serve a notice to declare a full plans approval of no effect. The Building Safety Act 2022 changed that for England.
This matters most on jobs that stall. If a client gets approval, digs footings and then runs out of money, the work may not have "commenced" in the regulation 46A sense at all, because the ground floor structure is not complete. After three years you could be making a fresh application, and the current Approved Documents will apply to it, not the edition the original design was drawn to. If a job is slipping, check the date the building notice was given or the full plans application was made, and where the work stands against regulation 46A.
What risk does a builder carry on a building notice?
This is the question that should drive the decision. On a building notice, nobody has confirmed the design complies before it is built. The risks fall on whoever is doing the work:
- Rework at your cost. If the inspector rejects a foundation depth, a beam or a drainage run, it comes out. If that is discovered after the next trade has followed on, the cost multiplies.
- Disputes over who pays. If the client supplied the drawings and they were wrong, you may still be the one standing in front of the inspector. On a fixed-price contract, decide in writing before you start who carries design risk.
- A 10-year enforcement window. Without passed plans, the section 36 power to require removal or alteration of non-compliant work now runs for 10 years in England. A shortcut that gets past one inspection is not safe after it.
- Dutyholder responsibilities. Since 1 October 2023 the dutyholder and competence requirements in Part 2A of the Building Regulations apply to all building work in England, not only higher-risk buildings. On a domestic job the contractor often takes on the principal contractor duties, and with a building notice there is less paperwork behind you to show how compliance was planned.
A good rule of thumb: the more of the job that is hidden once it is built (foundations, drainage, structure, fire separation), the stronger the case for full plans. Calculations and drawings agreed before work starts cost less than opening up finished work.
On a loft conversion, for example, the stair is one of the most common points of contention, and getting it right on paper first is easier than altering a built stair. Our stair calculator works through rise, going and pitch against Approved Document K before the joiner starts cutting.
Where does a registered building control approver fit?
You do not have to use the council. A registered building control approver (RBCA) can carry out building control instead. RBCAs replaced approved inspectors on 6 April 2024, under the Building (Registered Building Control Approvers etc.) (England) Regulations 2024.
The RBCA route has no building notice. The RBCA and the client jointly give an initial notice to the local authority. Work can start once the initial notice has been accepted, and it cannot start if the council rejects it. If the council does not reject the notice within the statutory period, it is treated as accepted. The initial notice lapses if the work has not commenced within three years of the notice being given.
From there, the RBCA reviews the plans and inspects the work much as a council would under full plans, and issues a final certificate at the end. The practical differences are mostly commercial: availability, response times, how the fee is structured and whether you have an ongoing working relationship. An RBCA cannot take on higher-risk building work, which stays with the Building Safety Regulator.
If an initial notice stops having effect, for example because the RBCA can no longer act, building control for the job can revert to the local authority. Keep your drawings, calculations and inspection records together so the handover does not stall the job.
Building control charges for both councils and RBCAs vary. Each local authority sets its own charges under its own scheme and publishes them, so get the figure from the authority or approver you plan to use.
Frequently Asked Questions
Can I switch from a building notice to full plans partway through a job? Yes, you can make a full plans application for the work, but the passed plans only protect work carried out in line with them. Anything already built under the building notice is still judged on what the inspector finds on site, so switching early is worth far more than switching late.
Do I need Building Regulations approval if I already have planning permission? Very likely, yes. Planning permission and Building Regulations approval are separate regimes run under separate law. Planning deals with whether the development is acceptable in that place; the Building Regulations deal with how it is built. Most extensions, loft conversions and structural alterations need Building Regulations approval whatever their planning position.
Can I start work before my full plans are approved? Yes, once you have given at least two days' notice of intention to start work under regulation 16. Until the plans are passed, though, you have no approved design behind the work, so anything built in that gap carries the same risk as building notice work.
What happens if work was done without any Building Regulations application? The owner can apply to the local authority for a regularisation certificate, which involves exposing enough of the work for building control to check it. It is slower and more disruptive than applying at the start, and the council can require alterations before it certifies anything.
Can a registered building control approver accept a building notice? No. The building notice is a local authority procedure only. With an RBCA, the work goes through an initial notice given jointly by the approver and the client, and the RBCA checks the plans and inspects the work under that notice.
For more England guides and calculators, see our England guides and calculators hub.
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