{
  "url": "https://openlegislation.uk/building-regulations-2010/regulation-23",
  "json_url": "https://openlegislation.uk/building-regulations-2010/regulation-23.json",
  "legislation": "uksi/2010/2214",
  "legislation_title": "The Building Regulations 2010",
  "legislation_url": "https://openlegislation.uk/building-regulations-2010",
  "path": "regulation/23",
  "kind": "regulation",
  "number": "23",
  "heading": "Requirements for the renovation or replacement of thermal elements",
  "text": "(1) Where the renovation of an individual thermal element—\n(a) constitutes a major renovation; or\n(b) amounts to the renovation of more than 50% of the element’s surface area;\nthe renovation must be carried out so as to ensure that the whole of the element complies with paragraph L1(a)(i) of Schedule 1, in so far as that is technically, functionally and economically feasible.\n(2) Where the whole or any part of an individual thermal element is proposed to be replaced and the replacement—\n(a) constitutes a major renovation; or\n(b) (in the case of part replacement) amounts to the replacement of more than 50% of the thermal element’s surface area;\nthe whole of the thermal element must be replaced so as to ensure that it complies with paragraph L1(a)(i) of Schedule 1, in so far as that is technically, functionally and economically feasible.",
  "extent": "E+W",
  "status": null,
  "version": "current",
  "annotations": [
    {
      "type": "F",
      "label": "F1",
      "text": "Reg. 23 substituted (E., but only in relation to educational buildings and buildings of statutory undertakers in W., Crown buildings in W., building work carried out or proposed to be carried out by Crown authorities in W., and excepted energy buildings in W.) (9.1.2013 for specified purposes, 9.7.2013 in so far as not already in force) by The Building Regulations &c. (Amendment) Regulations 2012 (S.I. 2012/3119), reg. 15, Sch. 1 (with reg. 1(3)(4), 45-47) (as amended by S.I. 2013/181, reg. 5, Sch.)"
    },
    {
      "type": "F",
      "label": "F2",
      "text": "Reg. 23 substituted (W. for remaining purposes) (19.4.2013 for specified purposes, 9.7.2013 in so far as not already in force) by The Building Regulations &c. (Amendment) (Wales) Regulations 2013 (S.I. 2013/747), regs. 1(4), 13 (with regs. 1(2)(3), 35, 36)"
    }
  ],
  "outstanding_effects": [
    {
      "type": "word substituted",
      "affecting": "uksi/2026/335",
      "affecting_title": "The Building Regulations etc. (Amendment) (England) Regulations 2026"
    }
  ],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/uksi/2010/2214/regulation/23",
    "retrieved_at": "2026-10-29T02:31:48.980832+00:00"
  },
  "licence": "Open Government Licence v3.0",
  "licence_url": "https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/",
  "attribution": "Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives."
}