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Page updated 12/02/2026
Most building work being carried out in the Republic of Ireland must comply with the Building Regulations. There are separate Building Regulations for 'Dwelling Houses' and 'Buildings other than Dwelling Houses'.
The Building Regulations 2024 state the following for external fire spread:
B4 - The external walls and roof of a building shall be so designed and constructed that they afford adequate resistance to the spread of fire -
a) over the face of the building; and
b) to and from neighbouring buildings.
The Building Regulations 2017 state the following for external fire spread:
B9 - The external walls and roof of a dwelling house shall be so designed and constructed that they afford adequate resistance to the spread of fire to and from neighbouring buildings.
There are two guidance documents which give practical guidance on common building situations to meet the requirements of the regulations:
Note that the materials, methods of construction, standards and other specifications (including technical specifications) which are referred to in the guidance documents are those which are likely to be suitable for the purposes of the Regulations. Where works are carried out in accordance with the guidance, this will indicate compliance with the Building Regulations. However, there may also be other ways to comply with the requirements than those described in the guidance documents.
