Planning Permission and Building Regulations

Planning Permission

You should always check to see if planning permission is required.

You won’t always need Planning Permission when building a Conservatory, but this depends on a number of things, including;

            • If the conservatory is closer to a public highway than the original building was , planning permission may be required.
            • How big the Conservatory will be in comparison to the size of the main building
            • Whether the main building has been previously extended

                    • The height and volume of the Conservatory

                    • Whether the main building is listed

                  • Whether the property is in a conservation area

You can find out about planning permission in England and Wales at the UK Government Planning Portal.

This site had some really good information and guides

            • Volume calculator for your conservatory

                    •  Costs for planning permission

                    • A facility to start a planning application online (only available for some local authorities)

                    • Links to local authorities throughtout England, Scotland and Wales                   

 Building Regulations 

There are a number of classes of new buildings or extensions of existing buildings that do not need Building Regulations approval. Amongst those are conservatories and porches, which are exempt from the Regulations provided that they meet the following criteria:

  • They are built at ground level
  • They are single storey
  • They have a floor area not greater than 30m²
  • The glazing accords with Part N of the Regulations i.e. protection against impact
  • Any electrical work that has its own ring main or is extended from a room classed as a special location i.e. kitchen complies with Part P of the Building Regulations – Electrical Safety

For the purposes of deciding whether the addition of a conservatory to an existing home requires Building Regulations approval, there is no definition of what a conservatory is. If however, no separation will remain between the existing home and the new conservatory it is likely that the conservatory will be judged as an conventional extension of the home, for which Building Regulations approval will be required.

The Building Regulations require that glazing with which people might collide, should be such that the risk of being injured is reduced.

The typical provision for glazing in a porch or conservatory will be to ensure that glazing in the following positions:

  • In windows, within 800mm of floor level (or 1500mm if within 300mm of a door); and
  • In doors, within 1500mm of floor level

should react in one of the following ways on impact:


  • Break in a way which is unlikely to cause injury
  • Resist impact without breaking
  • Be shielded or protected from impact

Although not likely to be a requirement of the Building Regulations, it is advisable to ensure that a conservatory does not make escape (in case of fire) from a window on the storey above more difficult. See

You can find details of Building Regulations for Scotland from the Scottish Building Standards website.

The Northern Ireland building regulations website
In addition to the main Building Regulations, you should also check with your Local Authority to ensure that there are no local by laws which may affect work.