Some buildings and extensions are exempt from the building regulations. The list gives you an idea of which build works are exempt.


  • A detached single storey building with an internal floor, no more than 30m², without bedrooms and is:
    • less than 1m from any boundary, or
    • built mostly of non-combustible material
  • A detached building with an internal floor no more than 15m² with no bedrooms.
  • Extending a building at ground level:
    • a conservatory, porch, covered yard or covered way, or
    • a car port open on at least two sides with floor no more than 30m²

Conservatories and porches with glazing must meet the requirements in Part K of the building regulations.

The exemptions do not include Part P which applies to electrical installations in greenhouses, small detached buildings, conservatories, porches, covered yard or way, carports, garden lighting and pond pumps.

Contact us if you are not sure.

Contact us

Building Control
Merton Civic Centre
London Road

Telephone: 020 8545 3145
Lines open 9-12am for booking site visits and 3-5pm for Technical queries

If you urgently need to report a dangerous structure: 020 8274 4901

Or out-of-hours emergency line: 020 8543 9750