Do I need building regulations?

The building regulations are a set of standards put in place by the Government to ensure that building work is carried out safely and correctly. If you build in accordance with the regulations, your home will be safe and comfortable for your family to live in. The best way to find out if you need building regulations approval is to check our list of projects below.

Projects that do not require building regulations approval:

  • Emergency boiler repairs
  • Adding power points or lighting points or any other alterations to existing electrical circuits (except around baths and showers)
  • Like-for-like replacements of baths, toilets, basins and sinks
  • Most repairs, replacements and maintenance work.

Home renovations, conversions and extensions

You can find further information and useful guides on our guidance for your project page.

Building new structures

Most home improvement work requires building regulations approval, but the following are referred to as exempt work if they meet certain criteria:

  • conservatories
  • porches
  • garages
  • carports
  • sheds and summerhouses
  • satellite dishes, aerials and antennae
  • garden walls.


A conservatory is a single-storey extension which has translucent or transparent material on at least three-quarters of the roof and half of the external walls. To be exempt, your conservatory must:

  • be at ground level only
  • have an internal floor area not exceeding 30m2
  • not be used for any other purpose e.g. kitchen or bedroom
  • keep the existing external doors and/or windows
  • have doors and windows that comply with Part K of the building regulations and safety glass must be used in critical locations
  • have independently controlled heating, if a heating system is to be installed
  • not make a new opening or increase the size of the existing one
  • have any fixed electrical points installed under Part P (Electrical Safety).

A porch

If your porch includes a cloakroom with a toilet/washroom you will need to make a building regulations application. To be exempt, your porch must:

  • be built at ground level only
  • have a floor area not exceeding 30m2
  • have doors and windows that comply with Part K of the building regulations
  • have any fixed electrical points installed under Part P (Electrical Safety)
  • keep the existing entrance door between the house and the porch
  • not affect access if the property has ramped or level access for disabled people.

Attached garages

Garages which are structurally connected to an existing house are classified as attached. Before building an attached garage, you will need to submit an application. An attached garage is treated in a similar fashion to an extension but:

  • not all the regulations apply, depending on the intended use of the building.
  • in the interest of fire safety, if there is a door between a garage and the dwelling it should have 30 minutes fire resistance and be self-closing. This opening must incorporate a step of at least 100mm between garage and dwelling floor.
  • the positioning of an attached garage must not affect the fire safety precautions of the existing house e.g. must not jeopardise an escape window either on the ground floor or the first floor.

Detached garages

A garage is detached if it is not structurally connected to a house and used for the storage of cars. To be exempt it must:

  • be less than 15m2
  • be single storey
  • not contain any sleeping accommodation.

If your garage is more than 15m2 but less than 30m2, you do not need to make a building regulations application providing it doesn’t contain sleeping accommodation and is either:

  • more than 1m from any boundary at any point
  • constructed substantially of non-combustible material

If the garage has a floor area exceeding 30m2 you will need to make a building regulations application and be aware of the following:

  • garages do not have to resist moisture penetration. Consequently, Building Control will not enforce the use of damp proof courses, membranes or other proprietary items for resisting rain penetration.
  • like any other extension, a garage is required to have a proper drainage system for rainwater drainage.
  • any part of a detached garage that is less than 1m from the boundary should be non-combustible.


You do not need to make a building regulations application if your carport:

  • is built at ground level
  • has an internal floor area which is less than 30m2
  • is open on at least two sides

Sheds and summerhouses

If you want to erect a small detached building in your garden, for example, a shed or summerhouse, you do not need to make a building regulations application if:

  • the floor area is less than 15m2 and the building does not include sleeping accommodation
  • the floor area is between 15m2 and 30m2, does not include sleeping accommodation and is either at least 1m from any boundary or constructed of substantially non-combustible materials.

Satellite dishes, aerials and antennae

The building regulations do not apply to satellite dishes, aerial and antennae but you should ensure that the installation is safe.

Garden walls

Building Regulations do not apply to garden walls. They may eventually collapse if they are not properly constructed or maintained. You should check them from time to time to see if any repairs are necessary or if they need rebuilding. Retaining walls near roads and footpaths are particularly at risk and may need a specialist if you see signs of damage or movement.