Not all buildings and extensions are subject to the Building Regulations. The most common domestic exemptions include:

  • domestic detached garages
  • domestic carports
  • domestic porches
  • domestic conservatories
  • domestic greenhouses

Small Single Storey Buildings

Any detached single storey building having a floor area less than 15m2 e.g. garden sheds.

Single Storey Detached Buildings

A detached building which is structurally unconnected to a dwelling, contains no sleeping accommodation, has a floor area not exceeding 30m2 and is either:

  • constructed substantially of non-combustible material, or
  • at any point greater than 1 metre from any boundary


An application is not required if the proposed carport:

  • is situated at ground floor level, and
  • has an internal floor area not exceeding 30m2, and
  • is open on at least 2 sides

Conservatories and Porches

All conservatories and porches are exempt from the regulations provided:

  • they form part of a domestic dwelling, and
  • they are located on the ground floor, and
  • they are single storey, and
  • they have a floor area less than 30m2, and
  • they have an external door leading from the dwelling to the conservatory or porch, and
  • the roof of the conservatory is translucent, and
  • the glazing complies with the safety requirements given in Part N of the regulations

It is advisable to ensure that any exempt structure does not restrict ladder access to windows needed as an emergency means of escape in case of fire.

If you are in any doubt as to whether your proposal requires an application, please call on 0151 691 8454 or email and we will assist you.