Building And Buildings, Wales Title, coming into force and application 1 1 The title of these Regulations is the Building (Amendment) (Wales) Regulations 2025 and they come into force on 20 December 2025. 2 These Regulations apply in relation to Wales. Amendments to the Building Regulations 2010 2 1 The Building Regulations 2010 are amended as follows. 2 In regulation 2(6) (interpretation)— a at the end of sub-paragraph (a)(iv), omit “and”; b for sub-paragraph (b), substitute— b “ relevant metal composite material ” means any panel or sheet, having a thickness of no more than 10mm, which is comprised of a number of layers— i two or more of which are made of metal, alloy or metal compound; and ii one or more of which is substantial and is made of a material having a gross calorific value of more than 35 MJ/kg when tested in accordance with BS EN ISO 1716:2018 entitled “Reaction to fire tests for products – Determination of the gross heat of combustion (calorific value)” (ISBN 978 0 580 93554 1) published by the British Standards Institution on 31 st July 2018; and for these purposes a substantial layer is one which is at least 1mm thick or has a mass per unit area of at least 1kg per m²; c “ specified attachment ” means— i a balcony attached to an external wall; ii a solar shading device (excluding a solar shading device attached to the wall at a height of no more than 4.5 metres above ground level); or iii a solar panel attached to an external wall; and d “ solar shading device ” means a device attached to the external surface of an external wall for reducing heat gain within a building by shading or deflecting sunlight. 3 In regulation 6(1)(c) (requirements relating to material change of use), for “fifteen” substitute “eleven” . 4 In regulation 7 (materials and workmanship)— a after paragraph (1), insert— 1A Building work must be carried out so that relevant metal composite material does not become part of an external wall, or specified attachment, of any building. ; b in paragraph (3)— i after sub-paragraph (d), insert— da fibre optic cables; ; ii in sub-paragraph (e), after “ground level”, insert “or up to 300mm above that level” ; iii after sub-paragraph (h), insert— ha components associated with a solar shading device excluding components whose primary function is to provide shade or deflect sunlight such as the awning curtain or slats; ; iv at the end of sub-paragraph (i), omit “or”; v at the end of sub-paragraph (j), insert— ; or k materials which form the top horizontal floor layer of a balcony which are of European Classification A1fl or A2fl-s1 (classified in accordance with BS EN 13501-1:2018 entitled “Fire classification of construction products and building elements. Classification using test data from reaction to fire tests” (ISBN 978 0 580 95726 0) published by the British Standards Institution on 14th January 2019) provided that the entire layer has an imperforate substrate under it. ; c in paragraph (4)(a)(iii), omit “(excluding any room in a hostel, hotel or boarding house)”. Transitional provisions 3 1 The amendments made by regulation 2 do not apply in any case where a building notice or initial notice has been given to, or full plans deposited with, a local authority before the day these Regulations come into force and either the building work to which it relates— a has started before that day, or b is started within the period of six months beginning with that day. 2 In this regulation— “building notice”, “ building work ”, “ full plans ” and “ initial notice ” have the meanings given by regulation 2(1) of the Building Regulations 2010; “ local authority ” has the meaning given by section 126 of the Building Act 1984 . Rebecca Evans Cabinet Secretary for Economy, Energy and Planning, one of the Welsh Ministers 17 June 2025