PLANNING RULES FOR LOFT CONVERSIONS AND ROOF EXTENSIONS

LOFT CONVERSIONS AND ROOF EXTENSIONS

DO YOU NEED PLANNING PERMISSION?

Loft conversions can be a great way of extending habitable space in a house without the need for a planning application.  Planning permission is not usually required ahead of internal loft conversion works.  Building Regulations approval and other consents are likely to be required in all instances.

External extensions to a roof space are more likely to require planning permission, however.

Planning applications cost money, take time, and require an assessment to be made by a local planning authority officer.  Your neighbours will be consulted and can object to your proposals. 

However, as with any extension to your house, you can undertake certain works without the need to apply for planning permission – subject to ‘permitted development’ rules being met in terms of extension size, type and location.    

The relevant rules are set out in the Town and Country Planning (General Permitted Development) (England) Order 2015, as amended.   

LOFT CONVERSIONS AND ROOF EXTENSIONS – PERMITTED DEVELOPMENT RULES

These are specific to “the enlargement of a dwellinghouse consisting of an addition or alteration to its roof” as detailed in Schedule 2, Part 1, Class B of the GPDO. 

There are different rules for:

• “any other alteration to the roof of a dwellinghouse” (Schedule 2, Part 1, Class C), which relate to the insertion of ‘skylights’ or re-roofing of roofs 
• “enlargement of a dwellinghouse by construction of additional storeys” (Schedule 2, Part 1 Class AA)  

An extension to a roof is classed as ‘permitted development’, not needing a planning application, where:

The height of the extension does not exceed the height of the highest point of the existing roof

The extension does not extend beyond the plane of any existing roof slope, which forms the principal elevation (usually the front) of the dwellinghouse and fronts a highway

The extension or alteration doesn’t consist of or include the construction or provision of a veranda, balcony*, or raised platform

The cubic content of the enlargements, as well as that of any previous enlargements to the roof, doesn’t exceed the cubic content of the original roof space by more than 40 cubic metres in the case of a terraced house or 50 cubic metres in any other case

*Balconies

The Government’s technical guidance states that: “A balcony is understood to be a platform with a rail, ballustrade or parapet projecting outside an upper storey of a building. A ‘Juliet’ balcony, where there is no platform and therefore no external access, would normally be permitted development.”

CONDITIONS

Development is permitted for roof extensions as described above, only subject to the following conditions:

The current house:

Must be a ‘dwellinghouse’ and does not contain any flats

Has not already had additional storeys added to it under previously used permitted development rights

Has not changed to be used as a house from a previous non-residential use under permitted development rights

Was not built as a ‘New Dwellinghouse’ under permitted development rights

Is not on Article 2(3) designated land (see protected areas section below)

Also,

The materials used in any exterior work must be of a similar appearance to materials used in the existing house

Any window inserted in a wall or roof slope forming a side elevation of the house must be obscure glazed and be non-opening unless the opening parts are more than 1.7 metres above the floor of the room in which the window is installed

Roof extensions, apart from hip to gable ones, must be set back, as far as practicable, at least 20 centimetres from the eaves of the original roof.  If removed, the existing eaves must be reinstated

Other than in the case of an enlargement which joins the original roof to the roof of a rear or side extension, no part of the enlargement extends beyond the outside face of any external wall of the original dwellinghouse