Technical guidance

What constitutes 'building work'?

  • The erection or extension of a building
  • The provision or extension of a controlled service or fitting in connection with a building. This includes sanitary equipment, unvented hot water storage systems, foul and surface water drainage, and combustion appliances
  • The replacement of a window (or a door with more than 50% of its area glazed)
  • The replacement of a heat-producing appliance or a hot water storage vessel
  • The insertion of insulating material into the cavity wall of a building
  • Work involving the underpinning of a building
  • Any alteration to a building, or part of a building, if it affects the structure, fire safety, or the access and use of the building
  • Any alteration to a controlled service or fitting
  • A material change of use of a building (or part of a building) to:
    • a dwelling
    • a flat or maisonette (including a change in the number of dwellings within a building)
    • a hotel or boarding house
    • an institution (nursing home, hospital, etc)
    • a public building (theatre, school, place of public worship, etc)
    • residential rooms (hotel rooms, student rooms, residential homes, etc) including a change in the number of rooms within a building
    • a shop
  • work relating to the energy status of the building.
  • work relating to thermal elements of the building (walls, floor and roof)

A ‘building’ is defined in the Building Regulations as "a permanent or temporary building, but not any other kind of structure or erection, and a reference to a building includes reference to a part of a building".

Building work requiring Building Regulations approval include:

  • New buildings
  • Extensions
  • Alterations to existing buildings
  • Loft conversions
  • Installation or alteration of drainage
  • Installation or alteration of combustion appliances
  • Structural alterations
  • Some changes of use 

Some building work does not need Building Regulations approval. Please refer to the section on Buildings Regulations exemptions.

Contact the team if you are unsure whether your work will need Building Regulations approval.

Types of work covered by the Building Regulations 

You will need approval for:

  • the erection or extension of a building
  • structural alterations to a building
  • any alteration which could affect the building's fire safety, disabled access or facilities 
  • the provision, alteration or extension of a controlled service or fitting, such as drainage or combustion appliances
  • a material change of use of a building, or part thereof
  • replacement windows, or doors with more than 50% of their area glazed
  • many types of electrical work in dwellings
  • work on thermal elements of a building (walls, floor and roof)

Examples of works requiring approval

  • Conversion of a loft space into rooms
  • Conversion of a dwelling house into flats
  • Conversion of a garage into rooms
  • Conversion of a barn into a dwelling
  • Internal alterations of a structural nature
  • Installation of cavity insulation
  • Installation of appliances and fittings for an unvented hot water system (a WC, bath, basin, sink etc)
  • Underpinning of foundations
  • Replacement roof covering (where substantially heavier or lighter than the previous covering)
  • Electrical work in dwellings and gardens of dwellings

Limitation On Requirements*

Building Regulations ensure reasonable health and safety for people who use a building or those affected by a building.

Building Regulations make no provision for property protection or the quality of finishes.

Building work must be carried out with the correct materials which should be used or fixed to a good standard.

Materials must conform to EC Directives, British Standards, British Board of Agrément (BBA) Certificate or other equivalent specification issued by a member of the EC.

* except for requirements for conservation of fuel, power, access and facilities for disabled people

Building Regulations Approved Documents

Click on the links below to find the most recent versions of the Approved Documents for the technical Parts (A to R) of The Building Regulations, together with Regulation 7.