A permitted development rear extension is the single storey extension beyond the rear wall of the original house that the householder classes allow without an application, to a depth set by whether the house is detached, within a height limit, and no nearer a boundary than the order allows at the eaves; the 3 meter rear extension most people search for is the standard depth on a semi or a terrace, and the deeper one on a detached house is the other figure. Beyond the standard depth the larger home extension scheme allows roughly twice it under prior approval larger home extension, a procedure in which the developer notifies the authority, the neighbours are consulted and the authority decides only on the effect on their amenity. Planning permission for rear extension is needed where the scheme leaves the class: a two-storey extension beyond its own limit, a depth beyond the larger home route, a house on designated land wanting the deeper depth, or a house whose envelope has already been spent. This page sets out the rear envelope as the developer reads it, and the side extension permitted development envelope sheet on this site reads the depth and the area from your house type and width.
The standard depth, the height and the boundary
Single storey rear extension permitted development reads from the rear wall of the original house: the depth allowed depends on whether the house is detached, the ridge may not exceed a height the order sets, and where the extension comes within a distance of a boundary its eaves are limited. The extension may not exceed half the curtilage with everything else built, may not go forward of a principal elevation and may not use materials out of keeping with the house. The envelope sheet returns the depth and the floor area from the house type and the width of the original rear wall, which is the reading the offer needs.
The larger home extension and the prior approval
The larger home extension scheme allows a deeper single storey rear extension, about twice the standard depth by house type, if the developer first gives the authority a prior approval notification with plans and the adjoining neighbours are consulted; if a neighbour objects the authority decides whether the effect on their amenity is acceptable, and if nobody objects within the period the development may proceed. It does not apply on designated land, and it is a right the vendor's particulars never mention because it needs a procedure; the sheet reads the deeper depth and the guide on permitted development for extensions sets out the rest of the class.
When it becomes an application, and what the file keeps
Rear extension planning permission is needed for anything beyond the class: a two-storey rear beyond its own depth limit, a depth past the larger home route, an extension on a house that has already used its envelope, a flat or a house created by a change of use which has no householder rights at all, and any house under an article 4 direction that has withdrawn the class. Curtilo Pro keeps the rear reading against the plot with the house type, the measurements and whether the larger route was used, so the offer, the prior approval and the file agree; the order and the technical guidance cited below are where the figures come from.
Questions people ask about permitted development rear extension
How far can a rear extension go under permitted development?
To the standard depth for the house type from the original rear wall, and to roughly twice it under the larger home extension route with prior approval, within the height and boundary limits. The sheet on this site reads both from your house type; the order cited below states the metres.
Do flats and converted houses have the rear extension right?
No. The householder classes apply to a dwellinghouse, not to a flat or to a building that became a house by a change of use under the order, and the sheet's reading does not apply to them; those need a planning application.
Does the larger home extension need the neighbours' consent?
No, it needs a prior approval notification; the neighbours are consulted and if one objects the authority decides on amenity. If nobody objects within the period the extension may proceed, and the guidance cited below explains the procedure.
Sources
- legislation.gov.uk, The Town and Country Planning (General Permitted Development) (England) Order 2015, Schedule 2 Part 1: the householder classes, the extension depths and widths, the outbuilding and porch limits and what designated land removes
- GOV.UK, Permitted development rights for householders: technical guidance, the government's reading of Part 1 with diagrams of the original house, the rear and side limits and designated land
- GOV.UK planning practice guidance, When is permission required: development, permitted development rights, prior approval and article 4 directions