Permitted development in conservation area is a shorter list than elsewhere, because a conservation area is article 2(3) land under the order and the householder classes are narrowed on it: the side extension goes entirely, so does cladding of any part of the exterior, the two-storey rear extension goes, outbuildings may not be built between a side elevation and the boundary, the larger home extension route does not apply, and several of the other parts of the order, class Q and class R among them, do not run at all. Conservation area permitted development that remains is the single storey rear at the standard depth, the porch, the outbuilding to the rear, hard surfaces and the like, and even those can be withdrawn by an article 4 direction, which is why the article 4 map the authority publishes is the second thing a developer reads after the designation. Permitted development in a conservation area is therefore a reading of two layers, the designation and the direction, and this page sets both out as the developer reads them at the viewing, with the envelope sheet on this site zeroing the side extension when designated land is set.
What goes, and what stays
On article 2(3) land the order withdraws the side extension, exterior cladding, the two-storey rear extension and outbuildings to the side of the house, and it does not offer the larger home extension route or the agricultural conversion classes; it keeps the single storey rear at the standard depth, the porch, outbuildings behind the house within the usual limits, and most minor works. Demolition of a building in a conservation area needs its own permission, and trees in it have their own notice regime, which the guide on the tree preservation order map covers.
The article 4 direction, and the map that shows it
An article 4 direction is the authority's own withdrawal of permitted development rights on named land, most often front elevations in a conservation area, house-to-HMO changes in student areas and garage conversions where parking is tight; once made, the withdrawn class needs a planning application. The direction is shown on the authority's constraints map or its article 4 schedule and is not on the national register, so the article 4 map is read authority by authority, and a developer who reads the designation without the direction has read half the constraint.
Reading the two layers, and what the file keeps
The developer reads whether the plot is in a conservation area from the authority's map, whether an article 4 direction covers it from the schedule, and then the envelope from what the order leaves; the sheet on this site takes designated land as an input for the first layer and the file keeps the second. Curtilo Pro keeps the designation, the direction and the day they were read against the plot, so the envelope the offer was built on is the envelope the file shows; the guidance cited below explains the historic environment designations and the direction procedure.
Questions people ask about permitted development in conservation area
Can I build a side extension in a conservation area under permitted development?
No. The side extension is withdrawn on article 2(3) land; it needs a planning application. The single storey rear at the standard depth remains unless an article 4 direction has withdrawn it.
Where do I find the article 4 map?
On the authority's own constraints map or in its article 4 schedule; there is no single national map. The direction names the land and the classes withdrawn, and the file on this site keeps it against the plot.
Does a conservation area affect class Q barn conversions?
Yes: class Q and class R do not apply on article 2(3) land, so a barn in a conservation area, a national park or an area of outstanding natural beauty needs a planning application. The class Q guide sets out the rest of the exclusions.
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 planning practice guidance, Conserving and enhancing the historic environment: conservation areas, listed buildings and what designation changes
- GOV.UK planning practice guidance, When is permission required: development, permitted development rights, prior approval and article 4 directions