No Building Regulations Completion Certificate? What It Means, Regularisation and the New 10-Year Limit

01

What a completion certificate is, and what it isn't

Under regulation 17, the relevant authority (normally the council's building control) must give a completion certificate within eight weeks of receiving the completion notice, where it is satisfied "after taking all reasonable steps" that the relevant provisions, which include the requirements of Schedule 1 to the Regulations, have been complied with (reg 17(1), (2) and (2A)).

Three points follow from the wording:

• It is evidence, not proof. Regulation 17(4): the certificate "shall be evidence (but not conclusive evidence) that the requirements specified in the certificate have been complied with". Regulation 17(5) requires the certificate to say so.
• The owner or builder has to trigger it. The person carrying out the work must give the authority a completion notice "not more than five days after that work has been completed" (reg 16(4)). No notice, no certificate.
• It says nothing about planning. The Law Society's TA6 notes put it plainly: "Building regulation approval is different from planning permission". The government's planning guidance makes the same point from the other side: a lawful development certificate "does not remove the need to comply with any other legal requirements such as the Building Regulations 2010" (PPG 17c-004). For the general explainer, see planning permission vs building regulations.

If a private approver (a registered building control approver) handled the job, the equivalent document is a final certificate that the approver gives to the council under the Building (Registered Building Control Approvers etc.) (England) Regulations 2024. The council can reject it within ten working days, and it too is "evidence (but not conclusive evidence)" of compliance (reg 13(3) and (4)).

02

Why a certificate might be missing

There are six common reasons, and the right fix depends on which one applies.

1. Nobody applied. Work done without a building notice, a full plans application or an approved route is "unauthorised building work" as regulation 18(8)(a) defines it.
2. The job was approved but never closed. The approval exists, but nobody gave the completion notice or booked the final inspection (reg 16(4) above), so no certificate was issued.
3. A private approver's notice lapsed. Under SI 2024/110 reg 19(3), if the building or extension is occupied and no final certificate is given, the approver's initial notice ceases to be in force on the expiry of eight weeks from the date of occupation (four weeks for some fire-safety-order buildings). The council then has powers over the partly completed work, including requiring the owner to supply plans and to cut into or lay open the work.
4. An installer self-certified. Windows, doors, boilers, electrics, roof coverings and several other jobs can be certified by an installer registered with a competent person scheme (for example Fensa, NAPIT, Certsure or CompetentRoofer; Gas Safe Register installers have the same responsibilities, although GOV.UK notes that the Register is not technically a competent person scheme). In that case there is no council completion certificate by design. Instead the installer must, within 30 days of finishing, give the occupier a copy of the certificate and notify the council (reg 20(3)).
5. The work was exempt. Schedule 2 exempts some buildings and extensions (see when you don't need one below).
6. The paperwork exists but is lost. Very often the certificate was issued and never passed on to the current owner.

03

How to check

1. Ask the council's building control team for the file for the address. Councils hold their own approvals and completion certificates. Ask for a final inspection or completion certificate record, not just the application.
2. Check for a competent-person notification. Councils must store the installer notices and certificates they receive in a retrievable form (reg 20(3A)). If a Fensa, Gas Safe, NAPIT or Certsure installer did the job, ask the installer and the scheme provider; the Law Society notes that a competent person certificate should have been provided once the work was completed (TA6 6th edition notes).
3. Check who did the job. A private approver gives its final certificate to the council, so ask the council and the approver. If the approver's notice lapsed, see reason 3 above.
4. Don't rely on a local search to tell you. The standard CON29 enquiry asks only whether the council has authorised proceedings for contravention of the building regulations (Q3.8, as reproduced by a council). A missing certificate, an informal complaint or an investigation does not appear unless it has become formal proceedings.

04

The real risk now: 10 years, not 12 months

You may read that "the council only has 12 months to act on building regulations breaches". That was the rule in England until 1 October 2023. It is now out of date.

The 10-year notice. Section 36 of the Building Act 1984 lets the council give the owner a notice to pull down or remove non-compliant work, or alter it to comply. Section 36(2)(a) expressly covers work carried out "without such an application having been made". A "section 36 notice" can no longer be given after the expiry of 10 years from the completion of the work (s36(4)). If the owner does not comply within 28 days, or a longer period allowed by the court or tribunal, the council can do the work itself and recover its costs (s36(3)). The change came into force in England on 1 October 2023.

It reaches older work. You may also read that "the 10-year limit only covers new work". The transitional provision, SI 2023/993 reg 7(2), keeps the old wording only for notices "given by a local authority ... before that date". It contains no saving for work completed before 1 October 2023. On the text, a notice served now is tested against the completion date of the work: work finished in, say, 2020 is inside the 10-year window.

Approved plans give protection. If you applied for approval, it was granted (and the work is not higher-risk building work), and the work was built in accordance with the approved plans and any council requirement, a section 36 notice cannot be given on the ground that the work breaks the regulations (s36(5) and (5A)). That is why a missing certificate matters far less than a missing approval.

Injunctions have no time limit. Section 36(6) preserves the right of the council, the Attorney General "or any other person" to apply for an injunction to remove or alter work that contravenes the regulations. The section sets no time limit.

The offence. Contravening the building regulations is an offence under s35(1), with up to two years' imprisonment or a fine on indictment (s35(4)(b)). The specific time limit for prosecution that used to sit in s35A has been omitted from 1 October 2023. Prosecutions already begun before that date stay under the old rules (SI 2023/993 reg 7(1)).

What the law does not tell you is how often councils use these powers. The statute gives the power; whether a particular council acts on a particular extension is a separate question, and that is why conveyancers deal with the issue as a risk to price and insure rather than a certainty of enforcement.

05

Your options

1. Late sign-off, where an approval exists

If a building notice or full plans application was made, ask building control to inspect and issue the certificate. Regulation 17(1) requires the authority to give a certificate where it is satisfied, "after taking all reasonable steps", that the relevant provisions have been complied with. What counts as reasonable steps is for the authority to decide.

2. A regularisation certificate (reg 18)

Regulation 18 is the statutory route for unauthorised building work. It is not a rubber stamp, and the process works like this:

• Scope. It applies where it appears to the authority that unauthorised building work "has been carried out on or after 11th November 1985" (reg 18(1)). Older work falls outside the regulation.
• Who applies. "The owner" applies in writing, with a statement that the application is made under reg 18, a description of the work, and, so far as reasonably practicable, a plan of the work and a plan of any extra work needed to bring it up to standard (reg 18(2)).
• The standard. The test is the building regulations "which were applicable to that work when it was carried out" (reg 18(2)(d)), not today's.
• Opening-up. The authority may require you to take reasonable steps "including laying open the unauthorised work for inspection by the authority, making tests and taking samples" (reg 18(3)). That can mean cutting into finishes, lifting floors or exposing foundations at your cost.
• Three possible outcomes. After those steps the authority tells you (a) what work it considers necessary, (b) that it "cannot determine" what work is required, or (c) that no work is required (reg 18(4)). Only if it is satisfied after taking all reasonable steps can it give the certificate (reg 18(5)).
• What the certificate is worth. It is, again, "evidence (but not conclusive evidence)" of compliance with the requirements it specifies (reg 18(6)).
• Cost. There is no national fee. Each council sets its charge under a published charging scheme. The 2010 charging regulations apply until the Building (Local Authority Charges and Amendments Relating to Charging) (England) Regulations 2026 (SI 2026/1094) take over on 6 November 2026. Those regulations list consideration of a reg 18 application and inspection of the work as a chargeable function (reg 4(1)(f)). Ask your council for its scheme.

One caution before you apply. An application tells the council the work exists. If you are selling and considering indemnity insurance instead, read the policy conditions first (next option) and decide the route before contacting building control.

3. Indemnity insurance

A lack-of-building-regulations indemnity policy is the quick, common answer in a sale. It does not fix the work. The one published sample wording we reviewed (ERGO/CLS sample policy, version dated 1 March 2016) pays out, on an enforcement notice, for legal costs, the cost of altering, demolishing or reinstating, and the fall in value caused by the enforcement action. Its statements of fact included that neither seller nor buyer had communicated with the local planning authority about building regulations irregularities, a general condition barred communicating about the insured risk with a third party without the insurer's consent, and it excluded loss arising from a retrospective building regulations application made without the insurer's prior written consent.

That sample dates from 2016, before the section 36 limit was extended, so treat it as an illustration of types of condition and read the current wording of any real policy. Our guide to planning indemnity insurance covers cost, cover and conditions in detail.

4. Renegotiate, or walk away

Buyers can ask the seller for a price reduction, a retention, or the cost of regularisation and any remedial work. If opening-up reveals defects, you have information the seller did not give you. Our buyer's guide covers the decision from the buying side.

06

When you don't need one: exempt buildings

Some buildings and extensions fall outside the Building Regulations entirely. Regulation 9 disapplies the Regulations to buildings and extensions of a kind described in Schedule 2. The two classes householders meet most are:

• Class 6, small detached buildings. A detached single-storey building with a floor area up to 30 m², no sleeping accommodation, that is either at least 1 m from the boundary of its curtilage or built substantially of non-combustible material; or a detached building up to 15 m² with no sleeping accommodation (no boundary rule).
• Class 7, extensions. A ground-level conservatory, porch, covered yard or covered way, or a carport open on at least two sides, with a floor area up to 30 m². A wholly or partly glazed conservatory or porch must have glazing that meets requirements K4 and K5.1 to K5.4 of Part K of Schedule 1.

Exempt does not mean "no rules at all". Reg 9(3) applies the electrical safety requirements (Part P) to Class 6 and Class 7 buildings that take their electricity from the dwelling, and reg 9(2) applies parts of Part G (water) where a water supply is shared with a dwelling. Adding sleeping accommodation later can also end the exemption: reg 5(f) treats it as a material change of use where a building described in Schedule 2 classes 1 to 6 stops being one. For a worked example, see building regulations for a log cabin.

Windows are the other frequent source of "missing certificate" worries. Replacement windows need either building control approval or an installer registered with a competent person scheme (see the scheme page, "Replacement windows, doors, roof windows or rooflights"). See do I need planning permission for new windows for the planning side, because a certificate from Fensa is not planning permission.

07

Selling: what the buyer's solicitor will ask

• The TA6. Sellers complete the Law Society's TA6 Property Information Form. The current edition is the 6th edition, mandatory for firms in the Conveyancing Quality Scheme from 30 March 2026 (Law Society press release). Its explanatory notes cover planning permission, building regulations and competent person certificates at questions 5.1 and 5.2, and tell sellers to give their solicitor the planning permissions and building control consents they have, and, if documents are lost or missing, to say so.
• The lender. If the buyer has a mortgage, the buyer's conveyancer works to the UK Finance Mortgage Lenders' Handbook. Part 1 paragraph 5.5 deals with planning and building regulations (the live site blocks automated access; here is an archived copy of Part 1 captured 6 March 2026). Para 5.5.1 says that where there is evidence of a breach but "in your professional judgment there is no reasonable prospect of enforcement action" and the conveyancer can provide an unqualified certificate of title, "we will not insist on indemnity insurance and you may proceed". Para 5.5.2 requires a report to the lender only where outstanding conditions will not be satisfied by completion and the conveyancer cannot give an unqualified certificate of title. The Handbook is voluntary for lenders, and individual lenders can have their own requirements.
• Be accurate. Answer the TA6 honestly. A seller who gives a wrong answer risks a claim under section 2(1) of the Misrepresentation Act 1967. The full seller's checklist, including planning and lawful development certificates, is in our guide to selling a house without planning permission.

08

Wales, Scotland and Northern Ireland

Wales. The Building Regulations 2010 apply in Wales with their own Welsh versions of regs 17 and 18. The 10-year limit in s36(4) and the omission of s35A took effect in Wales on 1 July 2026 (WSI 2025/1368, as shown in the amendment notes to s36). Before that date the 12-month limit still applied in Wales: the 2023 Welsh commencement order (WSI 2023/914 reg 2(b)(vi), as shown in the same amendment notes) brought section 39 into force only for making regulations.

Scotland. Scotland has its own system. A building warrant is needed before work starts, and doing the work without one is an offence (Building (Scotland) Act 2003 s8). If work has started without a warrant, an application "may be made at any time before a completion certificate has been accepted" (s15, late applications). Where work was done without a warrant, the person responsible must submit a completion certificate certifying compliance with the building regulations as they have effect on the date the certificate is submitted (s17(4) to (6)). The verifier can also grant permission for temporary occupation or use while no certificate has been accepted (s21).

Northern Ireland. The Building Regulations (Northern Ireland) 2012 have their own regularisation certificate (reg 13) and completion certificate (reg 14). Northern Ireland has not moved to 10 years: the legislation.gov.uk text of reg 19 lets a council serve a contravention notice under Article 18 of the Building Regulations (Northern Ireland) Order 1979 "up to 12 months after the date of receipt of a valid notice of completion". Check current Northern Ireland guidance before relying on this for a transaction.

09

Common myths

• "Planning permission covers building regs." It doesn't. They are separate systems with separate approvals (Law Society TA6 notes).
• "The council only has 12 months." Out of date in England since 1 October 2023 (s36(4)).
• "A completion certificate proves compliance." It is evidence, not conclusive evidence (reg 17(4)).
• "Regularisation is a rubber stamp." The council can require opening-up and can say it cannot determine what work is needed (reg 18(3) and (4)).

11

Sources

Every legal statement above is taken from the provision linked at that point. The main primary sources:

• Building Act 1984 s35, s35A (omitted) and s36
• SI 2023/993 reg 7: transitional savings; WSI 2025/1368 for Wales
• Building Regulations 2010: reg 5, reg 9, reg 16, reg 17, reg 18, reg 20 and Schedule 2
• Building (Registered Building Control Approvers etc.) (England) Regulations 2024, regs 19 and 22
• GOV.UK: competent person schemes (last updated 17 September 2026)
• SI 2026/1094 and the GOV.UK circular: council building control charges from 6 November 2026
• PPG: lawful development certificates, 17c-004
• Law Society TA6 (6th edition) explanatory notes and press release
• UK Finance Mortgage Lenders' Handbook, Part 1 (England and Wales), paras 5.5.1 and 5.5.2: archived copy captured 6 March 2026
• Misrepresentation Act 1967 s2
• Scotland: Building (Scotland) Act 2003 ss 8, 15, 17 and 21. Northern Ireland: Building Regulations (Northern Ireland) 2012 regs 13, 14 and 19 and Article 18 of the 1979 Order

This guide is general information, not legal advice. For a specific transaction, ask your conveyancer.