Going Up! More details of upward residential extensions...
Taking effect from the 31st August 2020, the Government has introduced new permitted development rights that allow existing residential properties to be increased in height by up to two additional stories where the existing property is already two or more storeys or one additional storey where the existing property is single storey.
This right does not apply to residential dwellings created by virtue of a previous conversion under permitted development rights, for example conversions from agricultural use to residential, or where additional storeys have already been added to the dwelling above the height of the dwelling as originally constructed. Furthermore, the rights do not apply to properties in sensitive areas such as Conservation Areas, National Parks, Areas of Outstanding Natural Beauty or World Heritage Sites or where the dwelling was constructed before 1st July 1948 or after 28th October 2018.
Various conditions apply in respect of the increased height of the dwelling, including that no part of the roof can exceed 18m in height and that the highest part of the roof must not exceed the highest part of the existing roof by more than 7m where already more than one storey or by more than 3.5m where the existing building is single storey. There are further height limitations in respect of both semi-detached and terraced properties, such that the highest part of the roof cannot exceed by more than 3.5m the height of the highest part of the roof of an adjoining property in the case of a semi-detached property or the highest part of the roof of every other building in the row of a terraced property. In addition to these limitations, the floor-to-ceiling height of any additional storey must not exceed 3m or the floor-to-ceiling height of any storey of the principal part of the dwelling and the storey must be constructed as part of the principal part of the dwelling. Whilst ‘reasonably necessary’ engineering works are permitted, they cannot be visible or attached to the exterior of the dwelling or involve works other than within the curtilage of the dwelling to strengthen existing walls or existing foundations.
In respect to design and appearance, the external materials are required to be similar to the existing dwelling, the roof pitch must be the same as the roof pitch of the existing dwelling and no window can be installed within any wall or roof slope forming a side elevation. The property must remain in residential use as a single dwelling (use class C3), i.e. occupied by either a single person or household, by not more than six residents living together as a single household with or without care provision, and not as a house of multiple occupation.
Notwithstanding the permitted right, it is necessary to first apply to the local council for ‘Prior Approval’ for consideration in respect of the impact on neighbouring properties and the external appearance, as well as air traffic and defence and in respect of protected vistas. Once approved, the works must be completed within 3 years of the prior approval.
At Tyler-Parkes we appreciate how complex these permitted development rights can be and we are able to offer both architectural and planning services to design a scheme that meets these conditions and limitations as well as prepare and co-ordinate the necessary documentation to support you through the planning process.
Amanda Stobbs, TPP
Photo by Jack Price-Burns