# The Building (Higher-Risk Buildings Procedures) (Wales) Regulations 2025, Regulation 46: Regularisation of unauthorised building work

Extent: E+W

(1) This regulation applies where it appears to the building control authority that unauthorised building work has been carried out on or after 11 November 1985.
(2) Where this regulation applies, the owner (in this regulation referred to as “the applicant”) may make an application in writing to the building control authority in relation to the unauthorised building work (“regularisation certificate application”).
(3) No regularisation certificate application may be made where unauthorised building work is a major change.
(4) The regularisation certificate application must be accompanied by—
(a) a statement that the application is made under this regulation;
(b) a description of the unauthorised building work;
(c) a plan of the unauthorised building work;
(d) where the application is made by someone on behalf of the owner, a statement signed by the owner confirming they agree to the application being made and that the information contained in the application is correct.
(5) Where the building control authority receives a regularisation certificate application, it may require the applicant to take such steps as the building control authority thinks appropriate for the building control authority to ascertain whether additional building work may be required in order for the unauthorised building work to secure compliance with the requirements of the building regulations which were applicable to that work when it was carried out.
(6) Where the building control authority is satisfied that additional building work is required to secure that the unauthorised building work satisfies the applicable requirements (taking account of any dispensation or relaxation given under sections 8 and 9 of, and Schedule 2 to, the 1984 Act), the building control authority must reject the application and an application for building control approval must be made in relation to the additional building work.
(7) Where the building control authority is satisfied, after taking all reasonable steps for that purpose that—
(a) the applicable requirements of the building regulations have been satisfied (taking account of any work carried out and any dispensation or relaxation given under sections 8 and 9 of, and Schedule 2 to, the 1984 Act), and
(b) no additional building work is required to secure that the unauthorised building work satisfies the applicable requirements (taking account of any such dispensation or relaxation),
the building control authority may give a certificate to that effect.
(8) The building control authority must send a copy of the certificate issued under this regulation to the local authority for the area in which the building is situated (if this is a different local authority).
(9) A regularisation certificate is evidence (but not conclusive evidence) that the applicable requirements of the building regulations specified in the certificate have been complied with in relation to the work specified in the certificate.
(10) Where a regularisation certificate is granted in relation to building work, Parts 2 to 5 of these Regulations cease to apply to that work.
(11) Where a regularisation certificate is granted the applicant must, no later than 5 working days after the certificate has been received, give the building work information and a copy of the certificate to the responsible person, if any, for the part of the building in relation to which the work described in the certificate relates.
(12) For the purposes of paragraph (11) the “building work information” is—
(a) where Part B of Schedule 1 to the 2010 Regulations imposes a requirement in relation to the unauthorised building work, information relating to—
(i) the design and construction of the building and the services, fittings and equipment provided in or in connection with the building;
(ii) the design of the change of use and building work to implement it;
(iii) the composition of materials used,
which will assist the responsible person to operate and maintain the building with reasonable safety;
(b) where paragraph F1(1) of Schedule 1 to the 2010 Regulations imposes a requirement in relation to the unauthorised building work, sufficient information about the building’s ventilation system and its maintenance requirements so that the ventilation system can be operated in such a way as to provide adequate means of ventilation;
(c) where paragraph L1 of Schedule 1 to the 2010 Regulations imposes a requirement in relation to the unauthorised building work, sufficient information about the building, the fixed building services and their maintenance requirements so that the building can be operated in such a way as to use no more fuel and power than is reasonable in the circumstances;
(d) where paragraph L2 of Schedule 1 to the 2010 Regulations applies in relation to the unauthorised building work, sufficient information about the system for on-site electricity generation in respect of its operation and maintenance requirements so that the system may be operated and maintained in such a way as to produce the maximum electricity that is reasonable in the circumstances and delivers this electricity to the optimal place for use;
(e) where Part O of Schedule 1 to the 2010 Regulations applies in relation to the unauthorised building work, sufficient information about the provision made under Part O so that the systems in place further to Part O can be operated in such a way as to protect against overheating.
(13) In this regulation—
“unauthorised building work” (“gwaith adeiladu anawdurdodedig”) means any building work in relation to a higher-risk building which is carried out without—
(a) a building control approval under regulation 7 or regulation 15 being granted by the building control authority;
(b) where the building work is a major change, a building control approval under regulation 24;
(c) where the building work is a notifiable change, a notification under regulation 18(3),
but work is not unauthorised building work to the extent that it consists only of scheme work or exempt work.

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Source: https://www.legislation.gov.uk/wsi/2025/1321/regulation/46 (the official version)
Page: https://openlegislation.uk/building-higher-risk-buildings-procedures-wales-regulations-2025/regulation-46
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.