Solicitor Kayleigh Chapman, in Blandy & Blandy’s planning & environmental law team, discusses Permitted Development Rights and extending buildings upwards.

The Town and Country Planning (General Permitted Development) (England) (Amendment) (No 2) Order 2020 (“2020 Order”) was made on July 20, 2020.

This 2020 Order made amendments to Permitted Development Rghts to allow upwards extension of dwellinghouses and detached blocks of flats. The provisions of the 2020 Order came into effect on August 31, 2020.

In respect of upward extensions to flats, the permitted development right introduced can be found at Class AA Part 20 of Schedule 2 of the 2020 Order. Further upwards extension Permitted Development Rights can be found at the new Classes AB-AD Part 20 and Class AA Part 1 of Schedule 2 of the 2020 Order.

The Permitted Development right is subject to a number of conditions and limitations, including the need to apply for prior approval to determine the impact on a substantive number of  different matters.

The Permitted Development Right under Class AA Part 20 only applies to purpose build detached blocks of flats. The right cannot be exercised in respect of flats which have been created by Permitted Development Rights.

Other restrictions include that the right cannot be exercised where a building is less than three storeys in height or where the highest part of the new roof would exceed the height of the existing building by more than seven metres. The final height of the building cannot also exceed 30 metres (although this limit does not include plant).

A prior approval application must be submitted in respect of the following prior to commencement of the development:

  • Transport and highways impacts of the development;
  • Air traffic and defence asset impacts of the development;
  • Contamination risks in relation to the building;
  • Flooding risks in relation to the building;
  • The external appearance of the building;
  • The provision of adequate natural light in all habitable rooms of the new dwellinghouses;
  • Impact on the amenity of the existing building and neighbouring premises including overlooking, privacy and the loss of light;
  • Whether because of the siting of the building, the development will impact on a protected view identified in the Directions Relating to Protected Vistas dated March 15,  2012 issued by the Secretary of State, and
  • Where the existing building is 18 metres or more in height, the fire safety of the external wall construction of the existing building.

There is both support and criticism of the new Permitted Development Right. The aspiration behind the Permitted Development Rights was to see a significant take up to boost housing delivery amidst the Covid-19 pandemic and the impact that that has had on construction and the economy generally.

The Government’s impact assessment for the 2020 Order suggested that at least 800 new homes per annum could be created by developers exercising the rights for upwards extensions.

Some commentators disagree with the estimate by the Government due to the significant number of matters that the council can consider in determining whether prior approval is needed and, if so, whether it should be granted.

There is also concern among existing leaseholders and tenants that the impact of development above their properties could lead to significant noise and amenity impacts during development and in some cases causes property damage to their existing properties (See Flat Owners Warning Over Rooftop Developments – BBC News). Damage to property is not a matter that the council can consider during the prior approval process, and indeed is not a planning consideration generally.

Whether or not there is significant take up of the right remains to be seen, as does whether the quality of development is sufficient to counter criticisms of the design of some dwellings created using earlier Permitted Developments (such as office to residential conversions).

Further, some local planning authorities have already taken steps to implement Article 4 directions to remove some of the newly created Permitted Development Rights.

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