What does a 'new or greater contravention' of the Building Regulations mean?

Material alterations or Extensions should not give rise to any ‘new or greater contravention’ in the existing building. That is, a material alteration or an extension (vertical or lateral) to an existing building should not make the existing building any worse in relation to Building Regulations. The following examples are given by way of clarification: The erection of an extension to an existing building whereby the extension is to be served for access and escape purposes by an existing staircase within the existing building: • If the existing staircase was adequate for the occupancy capacity of the existing building but inadequate for the extended building, this would constitute a ‘new contravention’ of Building Regulations. • If the existing staircase was inadequate for the existing building and rendered more inadequate due to the additional occupancy of the extended building, this would constitute a ‘greater contravention’ of Building Regulations. Note, therefore, that Building Regulations as they apply to works in connection with existing buildings being materially altered or extended, require solely that the 'status quo' be maintained in the existing building. Where an existing building contravenes Building Regulations, the material alteration or extension of such a building does not carry with it the requirement to make good such contravention, but merely that the contravention is not worsened, i.e. that no new or greater contravention arises. Building Regulations do not apply retrospectively to existing buildings where such buildings are being extended except to the extent that any new or greater contravention is not permitted.