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LONG READ :  Permitted Development. Upward extensions. The rules.

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The Government has introduced several new permitted development rights to allow upwards extensions to various existing properties including houses and commercial properties. The Town and Country Planning (General Permitted Development) (England) (Amendment) (No.2) Order 2020 will come into effect on 31 August 2020 and is the second phase of the Government’s permitted development rights relating to upward extensions.

So what’s allowed?

PD RIGHT TO EXTEND EXISTING HOMES

Class AA (enlargement of a dwelling-house by construction of additional storeys)

The new PD right allows existing houses which are detached, semi-detached or in a terrace to be extended upwards to provide additional living space by constructing additional storeys, subject to prior approval. The explanatory memorandum states that this right “could provide more space for growing families, or to accommodate elderly relatives, without having to move house” and that the measures will support economic recovery from COVID-19 by encouraging development.

The new Class AA (enlargement of a dwelling-house by construction of additional storeys) amends Part 1 of Schedule 2 of the Town and Country Planning (General Permitted Development) (England) Order 2015 and allows upwards extensions of up to two additional storeys on the topmost storey of a detached house, where the existing house consists of two storeys or more above ground level; or one additional storey above ground level on a detached house of one storey. In a terrace of 2 or more houses (which includes semi-detached houses) it also allows the construction of up to 2 additional storeys on the topmost storey of a house of 2 storeys or more, or 1 additional storey on a house of 1 storey above ground level. Existing accommodation in the basement or roof space of an existing house which includes a loft extension is not considered as a storey for the purposes of this PD right and the additional storeys must be built in the principal part of the house. The right applies to houses built after 1 July 1948 and before 28 October 2018. Engineering operations necessary for the construction of the additional storeys are allowed.

What isn’t?

  • Developments in Conservation Areas, National Parks and the Broads, areas of outstanding natural beauty or sites of special scientific interest.
  • Houses where permission was granted by a change of use under Class M, N, O, P, PA or Q of Part 3 of Schedule 2 of the Town and Country Planning (General Permitted Development) (England) Order 2015 (as amended); and
  • If the existing house has been enlarged by the addition of one or more storeys above the original house, whether in reliance on the permission granted by Class AA or otherwise.

Assuming you get through the “what’s allowed” hoops, there are further requirements:

  • that the building will not after the works be more 18 metres high;
  • that the overall height of roof after the works does not exceed the height of the highest part of the roof of the existing house by more than 3.5 metres, where the existing house is one storey, or 7 metres, where the existing house is more than one storey;
  • that where the house is in a terrace, its height cannot be more than 3.5m higher than the next tallest house in the terrace and in the case of a semi-detached house, the height of the highest part of the roof of the building with which it shares a party wall or which has a main wall adjoining its main wall;
  • that the floor to ceiling height of any additional storey, measured internally, will not be more than 3m in height or higher than the floor to ceiling height, measured internally, of any storey of the principal part of the existing house (whichever is lower);
  • that the development does not have visible support structures on it or attached to its upon completion;
  • that only engineering operations within the curtilage of the house to strengthen its existing walls or existing foundations are permitted;
  • a window cannot be installed in a wall or roof slope of a side elevation of an additional storey built under this right to prevent overlooking;
  • the roof pitch of the principal part of the house following works must be the same as the roof pitch of the existing house;
  • the external appearance of the materials used in the construction of the additional storeys must be of similar appearance to that of the existing house as with existing PD rights to extend houses;
  • homes extended using this right cannot be in use as a small house in multiple occupation, or change to that use;
  • the extended house must be used as a house (Class C3 of the Schedule to the Town and Country Planning (Use Classes) Order 1987 (“the Use Classes Order”)) except where the other purpose is ancillary to the primary use as a house; and
  • the developer must prepare a report setting out the proposed hours of operation and how they intend to minimise any adverse impacts of noise, dust, vibration and traffic movements during the building works on occupiers of the building and neighbouring premises before commencing works given the potential impact on neighbours during the construction of the additional storeys and any engineering works to strengthen the building.

The new development must be completed within 3 years from the grant of prior approval.

Prior Approval?

Yes, even though this is permitted development and a planning application is not required, prior approval must still be secured from the LPA before commencing works and the following matters must be considered:

  • the impact on the amenity of neighbouring premises including overlooking, privacy and overshadowing;
  • the design, including the architectural features of the principal elevation of the house, and of any side elevation which fronts a highway;
  • the impacts a taller building may have on air traffic and defence assets and on protected vistas in London;
  • The LPA will notify any adjoining owners or occupiers of the proposed development, as well as consulting with Historic England, the Mayor of London and London boroughs on protected views or the operator of a defence asset or aerodrome, the Civil Aviation Authority and Secretary of State for Defence if required. Where an aerodrome, technical site or defence asset is identified on a safeguarding map provided to the local planning authority, prior approval cannot be granted for development if an operator of a site, the Civil Aviation Authority or Secretary of State for Defence has responded to the consultation on the application indicating that that the development should not proceed.
  • The LPA must determine an application for prior approval within 8 weeks. The right does not provide a default deemed consent if the LPA fails to make a decision within this time. If a decision has not been made within 8 weeks there is a right of appeal to the Secretary of State for non-determination of the prior approval application.

PD RIGHT FOR THE CONSTRUCTION OF NEW HOMES

The Order also introduces four new permitted development rights, as Classes AA, AB, AC and AD of Part 20 of Schedule 2 of the 2015 Order, which subject to prior approval, permit 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 together with necessary engineering works. They 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 new rights apply to buildings built after 1 July 1948 and before 5th March 2018 and the additional storeys must be built in the principal part of the building.

The development must be completed within 3 years of the grant of prior approval.

Class AA –new dwelling-houses on detached buildings in commercial or mixed use

What’s allowed?

Class AA permits the construction of up to two new storeys of flats on top of existing, detached, free-standing buildings of 3 storeys or more above ground level in commercial or mixed use as shops (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 combining two or more of these uses including a mixed use with an element of housing.

Other requirements

  • that on 5 March 2018 the building was in the relevant commercial use or mixed use rehearsed above or residential use under Class C3 of the Schedule to the Use Classes Order;
  • that the right is subject to a maximum height limit for the newly extended building of 30 metres, excluding plant and the additional storeys must be built on the principal part of the building;
  • that the floor to ceiling height of any additional storey must not be more than 3m in height or higher than the floor to ceiling height of any storey of the principal part of the existing building (whichever is lesser);
  • that the overall height of the roof of the extended building must not be more than 7m higher than the highest part of the existing roof, excluding plant;
  • Development under Class AA(1)(a) (necessary engineering operations to construction the additional storeys and new flats) must not have visible support structures on or attached to the exterior of the building on completion nor consist of operations except for works within the curtilage of the building to (i) strengthen existing walls, (ii) strengthen existing foundations, (iii) install or replace water, drainage, electricity, gas or other services;
  • Development under Class AA(1)(b) (works for the replacement of existing plant or installation of additional plant on the roof of the extended building necessary to service the new flats) must have existing plant on the building and the height of any replaced or additional plant measured from the lowest surface of the new roof on the principal part of the extended building must not exceed the height of any existing plant as measured from the lowest surface of the existing roof on the principal part of the existing building;
  • Development under Class AA(1)(c) (works for the construction of appropriate and safe access to and egress from the new houses and existing premises in the building, including means of escape from fire, via additional external doors or external staircases) must not extend beyond the curtilage of the existing building; and
  • Development under Class AA (1)(d) (works for the construction of storage, waste or ancillary facilities) must not extend beyond the curtilage of the existing building or be on land forward of a wall forming the principal elevation of the existing building or on land forward of a wall fronting a highway and forming a side elevation of the existing building.

Class AB (new dwelling-houses on terrace buildings in commercial or mixed use)

What’s allowed?

Class AB permits the construction of new flats on top of terrace buildings (including semi-detached buildings) in the same commercial or mixed uses with an element of residential rehearsed above. Up to two storeys may be added if the existing building is two or more storeys tall above ground level, or one additional storey where the building consists of one storey.

Other requirements?

  • that on 5 March 2018 the building was in use in the relevant commercial use or mixed use as rehearsed above or within Class C3 of the Schedule to the Use Classes Order;
  • that the building will not, after the works,  be more than 18m high and no more than 3.5m higher than the next tallest building in the terrace (excluding plant);
  • that the floor-to-ceiling height of any additional storey will not be more than 3m in height or higher than the floor to ceiling height of any storey of the principal part of the existing building (whichever is lesser);
  • that the overall height of the roof of the extended building must not be more than 3.5m higher where the existing building is one storey or 7m higher where the existing building is more than one storey than the highest part of the existing roof, again excluding plant;
  • that the existing house has not been enlarged by the addition of one or more storeys above the original house, whether in reliance on the permission granted by Class AB or otherwise;
  • that development under Class AB(3)(a) must not include the provision of visible support structures on or attached to the exterior of the building upon completion of the development;
  • that development under Class AB(3)(a) (engineering operations reasonably necessary to construct the additional storeys and new dwelling-houses)must not consist of engineering operations other than works within the existing curtilage of the building to strengthen existing walls or foundations, or install or replace water, drainage, electricity, gas or other services;
  • that for Class AB(3)(b) development (works for the replacement of existing plant or installation of additional plant on the roof of the extended building reasonably necessary to service the new dwelling-houses)there must be existing plant on the building;
  • that for Class AB(3)(b) development, the height of any replaced or additional plant as measured from the lowest surface of the new roof on the principal part of the extended building must not exceed the height of any existing plant as measured from the lowest surface of the existing roof on the principal part of the existing building;
  • that development under Class AB(3)(c) (works for the construction of appropriate and safe access to and egress from the new dwelling-houses and existing premises, including means of escape from fire, via additional external doors or external staircases)must not extend beyond the curtilage of the existing building; and
  • that development under Class AB(3)(d) (works for the construction of storage, waste or other ancillary facilities reasonably necessary to support the new dwelling-houses)must not extend beyond the curtilage of the existing building, be situated on land forward of a wall forming the principal elevation of the existing building, or be situated on land forward of a wall fronting a highway and forming a side elevation of the existing building;

 

Class AC (new dwelling-houses on terrace buildings in use as dwelling-houses)

What’s allowed

Class AC permits the construction of new flats on top of terrace houses (including semi-detached houses); two storeys may be added if the existing building is two or more storeys tall above ground level, or one additional storey where the building consists of one storey above ground level.

Other requirements?

  • that on 5 March 2018 the building was in residential use under Class C3 of the Schedule to the Use Classes Order or the relevant commercial or mixed uses rehearsed above;
  • that the building will not, after the works, be more than 18m high and that highest the newly extended building of 18 metres, and it cannot be more than 3.5 metres higher than the next tallest house in the terrace;
  • that the floor-to-ceiling height of any additional storey will not be more than 3m in height or higher than the floor to ceiling height of any storey of the principal part of the existing building (whichever is lesser);
  • that the overall height of the roof of the extended building must not be more than 3.5m higher where the existing building is one storey or 7m higher where the existing building is more than one storey than the highest part of the existing roof;
  • that the existing house has not been enlarged by the addition of one or more storeys above the original house, whether in reliance on the permission granted by Class AA or otherwise;
  • that development under Class AC(2)(a)(engineering operations reasonably necessary to construct the additional storeys and new dwelling-houses) must not include the provision of visible support structures on or attached to the exterior of the building upon completion of the development;
  • that development under Class AC(2)(a) must not consist of engineering operations other than works within the existing curtilage of the building to strengthen existing walls or foundations, or install or replace water, drainage, electricity, gas or other services;
  • that development under Class AC(2)(b) (works for the construction of appropriate and safe access to and egress from the new dwelling-houses and existing premises, including means of escape from fire, via additional external doors or external staircases)must not extend beyond the curtilage of the existing building; and
  • that development under Class AC(2)(c) (works for the construction of storage, waste or other ancillary facilities reasonably necessary to support the new dwelling-houses)must not extend beyond the curtilage of the existing building, be situated on land forward of a wall forming the principal elevation of the existing building, or be situated on land forward of a wall fronting a highway and forming a side elevation of the existing building;

 

Class AD (new dwelling-houses on detached buildings in use as dwelling-houses)

What’s allowed?

Class AD permits the construction of additional storeys on detached houses; two storeys may be constructed on the top most storey of a detached house if the existing building is two or more storeys tall above ground level, or one additional storey where the building consists of one storey above ground level.

Other requirements:

  • that the buildings have to have been in residential use under Class C3 or in the relevant commercial or mixed uses rehearsed above on 5 March 2018;
  • that the right is subject to a maximum height limit for the newly extended building of 18 metres;
  • that the floor-to-ceiling height of any additional storey will not be more than 3m in height or higher than the floor to ceiling height of any storey of the principal part of the existing building (whichever is lesser);
  • that the overall height of the roof of the extended building must not be more than 3.5m higher where the existing building is one storey or 7m higher where the existing building is more than one storey than the highest part of the existing roof;
  • that the existing house has not been enlarged by the addition of one or more storeys above the original house, whether in reliance on the permission granted by Class AA or otherwise;
  • that development under Class AD(2)(a)(engineering operations reasonably necessary to construct the additional storeys and new dwelling-houses) must not include the provision of visible support structures on or attached to the exterior of the building upon completion of the development;
  • that development under Class AD(2)(a) must not consist of engineering operations other than works within the existing curtilage of the building to strengthen existing walls or foundations, or install or replace water, drainage, electricity, gas or other services;
  • that development under Class AD(2)(b) (works for the construction of appropriate and safe access to and egress from the new dwelling-houses and existing premises, including means of escape from fire, via additional external doors or external staircases)must not extend beyond the curtilage of the existing building; and
  • that development under Class AD(2)(c) (works for the construction of storage, waste or other ancillary facilities reasonably necessary to support the new dwelling-houses)must not extend beyond the curtilage of the existing building, be situated on land forward of a wall forming the principal elevation of the existing building, or be situated on land forward of a wall fronting a highway and forming a side elevation of the existing building;

 

Conditions applicable to Classes AA, AB, AC and AD

  • The PD rights apply to houses and buildings in certain commercial or mixed uses built after 1 July 1948 and before 5th March 2018. Houses and buildings have to have been in one of the relevant uses or mixed uses on 5 March 2018.
  • The development must be completed within 3 years of the grant of prior approval.
  • The rights to build additional storeys allow engineering operations necessary for the construction of the additional storeys, the replacement or installation of additional plant (as appropriate), construction of safe access and egress and construction of storage, waste or ancillary facilities, if necessary. These rights do not allow for these additional works to be undertaken without the construction of the new storeys and homes.
  • The appearance of the materials used in the construction of the additional storeys must be similar to that of the existing house.
  • 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.
  • Homes extended using these rights cannot be in use as a small house in multiple occupation, or change to that use.
  • The right does not apply in Conservation Areas, National Parks and the Broads, areas of outstanding natural beauty, or sites of special scientific interest, or if the building is a listed building or on land within its curtilage; a scheduled monument or land within its curtilage; a safety hazard area; a military explosives storage area; or land within 3 kilometres of the perimeter of an aerodrome.
  • The applicant must prepare a report setting out the proposed hours of operation and how they intend to minimise any adverse impacts of noise, dust, vibration and traffic movements during the building works on occupiers of the building and neighbouring premises before commencing works under these rights.

Prior Approval

Prior approval from LPA must be obtained, which will consider the following impacts:

  • 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 including (i) the design and the architectural features of the principal elevation of the house and any side elevation which fronts a highway and (ii) the impact of any ancillary works relating to access, storage, waste under each class;
  • the provision of adequate natural light in all habitable rooms of the new flats;
  • amenity of the existing building and neighbouring premises including overlooking, privacy and loss of light;
  • impacts of noise from any commercial premises on the intended occupiers of the new flats (for Classes AA and AB);
  • impacts of the introduction of or an increase in a residential use of premises in the area on the carrying on of any trade, business or other use of land in the area (for Classes AA and AB);
  • whether because of the siting of the building the development will impact on a protected vistas in London;
  • the LPA will notify any adjoining owners or occupiers of the proposed development, as well as consulting with Historic England, the Mayor of London and London boroughs on protected views or the operator of a defence asset or aerodrome, the Civil Aviation Authority and Secretary of State for Defence if required. Where an aerodrome, technical site or defence asset is identified on a safeguarding map provided to the LPA, prior approval cannot be granted for development if an operator of a site, the Civil Aviation Authority or Secretary of State for Defence has responded to the consultation on the application indicating that that the development should not proceed;
  • the LPA is required to make a decision on an application for prior approval under the right within 8 weeks and the deemed consent provisions do not apply if the LPA fails to make a decision within this time, although there is a right of appeal after 8 weeks to the Secretary of State for non-determination of the prior approval application.

 

Building Better, Building Beautiful vs Build, Build, Build

There remains a distinct tension between the Government’s aims for “building better, building beautiful” and the “build, build, build” agenda recently announced by Boris Johnson and it will be interesting to see how the two sit together. Whilst some effort has been made to maintain architectural symmetry and one of the noble aims of the proposals are to help growing families and support multi-generational living by accommodating the elderly, we are likely to see a changing and chequered sky line through these grand designs under PD.

Planning pundits are in two minds as to how much take up there will be given the complex and detailed requirements which may in reality be closer to a planning application than prior approval as we know it. The lack of s106 contributions and affordable housing provisions makes the PD route an attractive option to small developers who have been hit hard by the impact of COVID-19 but the fees for prior approval under these rights will be higher than for previous prior approvals. The expansion of PD rights is not a solution to the housing problem and the importance of high quality private and public amenity space, acutely highlighted by lockdown but building upwards is a step change and it is encouraging that the Government continues to seek to address some of the concerns previously expressed over the quality of accommodation delivered through PD by including natural light and amenity considerations.

One thing is for certain, the rapid expansion of PD rights for upwards extensions shows that the Government is serious about fast tracking and streamlining the planning system and getting away from the delays of newt-counting so eloquently put by Boris Johnson in his recent speech on job creation. As advised in our article, The only way is up – or is it? , about the first phase of PD rights for upwards extensions,  there are a lot of hoops to jump and hurdles to overcome (as demonstrated in our earlier article HERE) so it is critical to understand the process before embracing the new horizons promised by these PD rights.