The building regulations of UK include procedural and technical provisions. Some home extensions are exempt from certain aspects. Even in this case these extension may require planning permission.

Exemptions are provided as per the seven classes of Schedule 2 of the Building Regulations. Class 1 includes buildings controlled under legislation, Class 2 includes buildings not frequented by people, Class 3 includes greenhouses, Class 4 includes temporary buildings, Class 5 includes Ancillary buildings, Class 6 includes Small detached buildings, and Class 7 includes Extensions.

Significantly, the Building Regulations 2010 exemption criteria are applied to Part L (Conservation of fuel and power) requirements. These include is a roofed construction having walls; and a home that uses energy to condition the indoor climate.

Building Regulations also do not apply to

  • Certain buildings listed in conservation areas or schedule of monuments. Here, the compliance with the energy efficiency requirements would unacceptably alter their character or appearance.
  • Buildings meant for worship
  • Temporary buildings planned for usage of 2 years or less, and have a low energy demand
  • Industrial sites, workshops and non-residential agricultural buildings with low energy demand
  • Stand-alone buildings with total useful floor area of less than 50m²