Permitted development rights for the construction of new homes - above existing homes and some commercial uses

The Government have made potentially sweeping changes to permitted development rights in England.Under new permitted development rights recently announced, full planning permission for the extension of existing commercial buildings and residential buildings will no longer be required to extend upwards for the construction of new self-contained homes by allowing additional storeys to be constructed on free-standing blocks and on buildings in a terrace in certain commercial uses, and in mixed uses with an element of housing. The rights will also allow additional storeys to be constructed on existing houses which are detached or in a terrace (which includes semi-detached houses) to create new self-contained homes.The changes will take effect on 31 August 2020. A copy of the draft legislation is here.These provisions are the second phase of new permitted development rights relating to the upward extension of buildings. A new right (Class A to Part 20 of the GDPO) allowing existing purpose-built detached blocks of flats to extend upwards to create new self-contained homes in England comes into force on 1 August 2020 and is discussed in our previous post. Jump ahead:

• Part 20 Class AA: new dwelling houses on detached buildings in commercial or mixed use;
• Part 20 Class AB: new dwelling houses on terrace buildings in commercial or mixed use;
• Part 20 Class AC: new dwelling houses on terrace buildings in use as dwelling houses and Part 20 Class AD: new dwelling houses on detached buildings in use as dwelling houses;
• Obtaining Prior Approval for all of the above; and
• Initial comments

Part 20 Class AA: new dwelling houses on detached buildings in commercial or mixed use

Class AA (part 20) allows for the erection of up to two additional storeys on the topmost storey on the principal part of the building. To benefit from this class, the existing building must be free-standing and be used as shops (Class A1), financial and professional services (Class A2), restaurants and cafes (Class A3), or offices (Class B1(a)), or as betting shops, pay day loan shops or launderettes, or in mixed use between these uses or a mixed use with an element of housing. These uses are already able to change use to residential uses under existing permitted development rights elsewhere in the GDPO.As with most permitted development, this Class AA right is subject to a number of exclusions:

• on 5 March 2018 the building must have not been in use other than for the above commercial/acceptable mixed use uses;
• the new PD right only applies to existing dwellings built between 1 July 1948 (when the current planning system was created) and 5 March 2018 (when the proposal was first announced);
• the right is restricted when the building is a listed building or within a Conservation Area, National Park and the Broads, area of outstanding natural beauty, or a site of special scientific interest.
• the existing building must be 3 or more storeys above ground level;

There are also a number of restrictions on the works permitted, including, but not limited to:

• a 30m maximum height limit for the newly extended building, but not more than 7m than the existing height. This height limit recognises sensitivities around local amenity and is considered to be practical in terms of carrying out the building works;
• the development cannot include any engineering operations other than works within the curtilage of the existing house to strengthen existing walls and foundations;

Existing accommodation in the roof space of the existing commercial building or house, including a loft extension, is not considered as a storey for the purposes of these rights.

Part 20 Class AB: new dwelling houses on terrace buildings in commercial or mixed use

The draft legislation also introduces a new PD right (Class AB of Part 20) to allow buildings in a terrace (of 2 or more attached buildings) in commercial or mixed use to create up to two additional storeys for use as flats. Class AB allows for up to 2 additional storeys of new homes to be constructed on the topmost storey of a building of 2 storeys or more above ground level, or 1 additional storey on a building of 1 storey above ground level. The overall height of the building when it is extended cannot be greater than 18 metres in height, 3.5 metres taller than the existing building when it consists of one storey and 7 metres when it consists of two storeys, and no more than 3.5 metres higher than the next tallest building in the terrace. To benefit from Class AB on 5 March 2018 the building must not have been in a use except as a shop (Class A1), financial and professional service (Class A2), restaurant and cafe (Class A3), or offices (Class B1(a)), or as betting shops, pay day loan shops or launderettes, or in mixed use between these uses or a mixed use with an element of housing. Class AB rights do not apply to buildings constructed before 1 July 1948 or after 5 March 2018, to buildings which are listed and/or in a Conservation Area, National Park and the Broads, area of outstanding natural beauty, or a site of special scientific interest. They are also restricted when the building has already been enlarged by the addition of one or more storeys above the original building. We refer you to the legislation here for further details.

Part 20 Class AC: new dwelling houses on terrace buildings in use as dwelling houses and Part 20 Class AD: new dwelling houses on detached buildings in use as dwelling houses

Two further permitted development rights (Class AC and Class AD of Part 20) are  introduced to allow additional storeys to be built on existing Use Class C3 dwelling houses which are in a terrace (which includes semi-detached houses) (Class AC) or detached (Class AD)  to create new self-contained homes. Up to 2 additional storeys of new homes can be constructed on the topmost storey of a C3 dwelling house of 2 storeys or more above ground level, or 1 additional storey on a dwelling house of 1 storey above ground level. The right is subject to a maximum height limit for the newly extended building of 18 metres, the extended building can only be 3.5 metres taller than the existing building when it consists of one storey and 7 metres when it consists of two storeys. In respect of Class AC it cannot be more than 3.5 metres higher than the next tallest house in the terrace. As with Class AB rights, these rights do not apply to buildings constructed before 1 July 1948 or after 5 March 2018, to buildings which are listed and/or in a Conservation Area, National Park and the Broads, area of outstanding natural beauty, or a site of special scientific interest. They are also restricted when the building has already been enlarged by the addition of one or more storeys above the original building. We refer you to the legislation here for further details.

Obtaining Prior Approval for all of the above

Where any development under these classes are proposed, the developer must first apply to the local planning authority for Prior Approval providing information on the following:

• For all four classes:
  • transport and highways impacts of the development;
  • air traffic and defence asset impacts of the development;
  • contamination risks;
  • flooding risks;
  • the provision of adequate natural light in all habitable rooms;
  • whether, because of the siting of the building, the development will impact on a protected view; and
  • the external appearance of the building, including the design and architectural features of the principal elevation and any side elevation that fronts a highway;

• For Classes AA and AB only:
  • Impacts of noise from any commercial premises on the intended occupiers of the new dwellings;
  • Impacts of the introduction of, or an increase in, residential use in the area;
  • Impacts on the amenity of the existing building and neighbouring premises including overlooking, privacy and the loss of light;

• For Class AC and AD only:
  • Impacts of the amenity of the neighbouring premises including overlooking, privacy and the loss of light

• For Classes AB, AC, and AD only:
  • the impact of any works for the construction of appropriate and safe access to/from the new dwellings and existing premises and for the construction of storage, waste or other ancillary facilities reasonably necessary to support the new dwellings

Any Prior Approval will be subject to the following conditions:

• That the redevelopment must be completed within 3 years from the grant of the Prior Approval;
• Pre-commencement condition for the agreement with the local authority of a construction management report (including how to mitigate adverse impacts of noise, dust and vibration and the proposed use of materials), which the developer must then comply with when carrying out the development;
• Notification of the completion date; and
• Any new dwelling house must remain as a C3 use except if the other purpose if ancillary to the primary use as a dwelling house.

Initial comments

These new PD rights provide the opportunity to 'build upwards' on a number of buildings, without the need for full planning permission. There are however many limitations and conditions and we consider that realistically this will limit the application of these particular permitted development rights. The scope of the Prior Approval now includes matters which require subjective judgement, and therefore no not necessarily allow for a 'light touch process' which was the purpose of the Prior Approval regime.Like any other PD works, CIL liability (subject to exemptions and reliefs) will be applicable (if applicable in a given area) but affordable housing will not be. Given the extent of the recent PD changes to create residential dwellings we wonder whether the Government may alter the Planning Practice Guidance to facilitate some form of affordable housing provision.It is worth remembering that greater flexibility via permitted development rights does not mean that using them will be appropriate/possible, for example:

• Are any restrictions within the existing planning permission(s) (i.e. condition on maximum building height) and associated section 106 planning obligations;
• Is any current/historic enforcement action;
• Signage/advertisement consent;
• Building regulation requirements;
• Right to light potential issues; and
• Any restrictions imposed in the title documentation, including any lease, which would fetter the ability to use these rights.

If you have a site which you consider may benefit from this right our team of in-house chartered town planners are here to assist and are backed up by our specialist planning lawyers. You can find contact details here. We would also refer to our other articles which note the key points and the potential impact of the other recently announced PD rights being:

• Demolition and Redevelopment of Vacant Residential/Commercial Buildings
• Upward Extensions of Existing Homes to create more space within the same dwelling