What is Permitted Development UK — Complete Guide
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What is Permitted Development in the UK? Complete Guide
Permitted development (PD) rights are one of the most important — and least understood — aspects of the UK planning system. Understanding them can save you time, money, and the uncertainty of a planning application. This complete guide from Crown Architecture & Structural Engineering explains what permitted development is, what you can do under it, and when you will still need planning permission.
What is Permitted Development?
Permitted development rights are a set of national planning permissions granted by Parliament through the Town and Country Planning (General Permitted Development) (England) Order 2015 (as amended). They allow homeowners to carry out certain types of work on their homes without needing to apply for planning permission from their local planning authority.
In effect, PD rights mean that Parliament has already decided, at a national level, that certain works are acceptable in principle — subject to defined limits and conditions. The local planning authority has no role in approving or refusing works that genuinely fall within PD rights.
PD rights apply to houses. They do not apply to flats, maisonettes, commercial buildings, or land. They also do not apply to listed buildings, or to properties in designated areas where the rights have been specifically removed or restricted.
What Can You Do Under Permitted Development?
Rear Extensions
Single-storey rear extensions up to 3 metres deep (terraced/semi-detached) or 4 metres deep (detached) are permitted development, subject to height and design conditions. Under the Neighbour Consultation Scheme, larger extensions up to 6m or 8m may be permitted subject to a prior approval process. See our detailed guide on house extensions in London.
Loft Conversions
Loft conversions are permitted development if the volume added does not exceed 40m³ (terraced) or 50m³ (semi-detached/detached), the roof is not raised above the highest point of the original roof, and no balconies or verandas are added. Side-facing windows must be obscure-glazed. Learn more in our guide on loft conversions in London.
Outbuildings
Garden buildings, sheds, garages, and other outbuildings in the garden are permitted development provided they are single-storey, the eaves height does not exceed 2.5 metres, the maximum overall height does not exceed 4 metres (dual pitch) or 3 metres (any other roof), and the building is not in front of the principal elevation of the house. The outbuilding cannot occupy more than 50% of the land around the original house (when combined with any other extensions or outbuildings).
Side Extensions
Single-storey side extensions are permitted development where they are no wider than half the width of the original house, are single-storey (no more than 4m high), and use similar materials to the original house. However, in conservation areas and other designated areas, side extensions visible from a highway are not permitted development.
Porches
Porches are permitted development if they are no more than 3 square metres in footprint (measured externally), no more than 3 metres in height, and more than 2 metres from any boundary with a highway.
Rooflights / Velux Windows
Installing roof windows is permitted development provided they do not protrude more than 150mm above the roof plane on the principal or side elevation facing a highway, and are not higher than the ridge. Solar panels can also be installed under permitted development in most circumstances.
What is NOT Permitted Development?
The following works always require planning permission, regardless of size:
- Works to a listed building (which also require listed building consent)
- Works in certain designated areas where PD rights have been removed (see below)
- Converting a house into flats
- Adding a new dwelling or self-contained unit
- Works that materially alter the external appearance in ways not covered by PD rights
- Changes of use of the building (unless covered by specific PD rights for change of use)
The Original House Rule
One of the most important concepts in permitted development is the original house rule. When calculating whether your extension is within the permitted development limits, the measurements are taken from the original house as it was built, or as it stood on 1 July 1948 (whichever is later). This means that any previous extensions or alterations are ignored when measuring the depth, but they count towards the 50% coverage rule. If you buy a house that has already been extended, any further extension must still be within the PD limits measured from the original house.
How to Confirm Permitted Development Rights
The safest way to confirm that your proposed works are permitted development is to apply for a Lawful Development Certificate (LDC) from your local planning authority. An LDC is a formal legal document confirming that the works described are lawful. It costs half the planning fee (currently £129 for a householder LDC) and takes around 8 weeks.
An LDC is not legally required before commencing permitted development works, but it is strongly recommended — especially if you plan to sell the property in the future, as solicitors and buyers will want evidence that works were lawfully carried out.
When Are PD Rights Removed?
Article 4 Directions
A local planning authority can issue an Article 4 Direction to remove some or all permitted development rights in a defined area. These are most commonly used in conservation areas, where they may require planning permission for works that would otherwise be PD (such as replacing windows, adding a satellite dish, or changing the roof material). You can check whether your property is affected by an Article 4 Direction by contacting your local planning authority or checking your council’s website.
Conservation Areas, AONBs, and National Parks
In conservation areas, Areas of Outstanding Natural Beauty, National Parks, and World Heritage Sites, additional restrictions apply. For example, any side extension visible from a highway is not permitted development, and cladding the exterior of a house is not permitted development. Crown Architecture in Hackney and Crown Architecture in Islington have extensive experience navigating conservation area restrictions across London.
Conditions Imposed at Planning Stage
When a house is built or an earlier extension is approved, the planning permission may include a condition removing permitted development rights. This is sometimes used to ensure the character of new developments is maintained. You can check whether such conditions apply by reviewing the planning history of your property on your council’s planning portal.
Permitted Development in Wales, Scotland, and Northern Ireland
This guide covers permitted development rights in England only. Wales, Scotland, and Northern Ireland each have their own separate permitted development regimes, which differ in important respects. If your property is in Wales, Scotland, or Northern Ireland, please contact us for specific advice.
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Frequently Asked Questions
Do I need to notify anyone before carrying out permitted development works?
For most permitted development works, you do not need to notify your local planning authority before starting. However, for larger rear extensions under the Neighbour Consultation Scheme (6m or 8m depth), you must submit a prior approval application to the LPA before commencing. You may also need to apply for building regulations approval and serve a Party Wall Notice on your neighbours, depending on the nature of the works.
Can I lose permitted development rights after buying a house?
You may find that permitted development rights have already been removed from a property before you buy it — either by a condition on an earlier planning permission, by an Article 4 Direction, or because the property is in a designated area. Crown Architecture always checks the planning history and constraints for a property at the start of a project to identify any such restrictions.
Does permitted development apply to blocks of flats?
No. Permitted development rights for householder works (extensions, loft conversions, outbuildings, etc.) apply to houses only. Flats, maisonettes, and other types of dwelling do not benefit from these rights. If you own a flat and wish to extend or alter it, you will need to apply for planning permission.
What is the 4-year rule for permitted development?
The 4-year rule (now changed to 4 years under the Levelling-Up and Regeneration Act 2023) previously meant that if a building had been in use or an operational development had been carried out for 4 years without enforcement action, it became immune from enforcement. However, the rules have been updated and the limitation period for most breaches of planning control is now 4 years from the date of the breach. Always seek professional advice if you are relying on this provision.
Can permitted development rights be used for a home office in the garden?
Yes. A garden office or outbuilding is permitted development provided it meets the conditions: single-storey, eaves no higher than 2.5m, overall height no more than 4m (dual pitch) or 3m (flat/other roof), not in front of the principal elevation, and not covering more than 50% of the garden. The building must not be used as separate residential accommodation (i.e., you cannot sleep in it independently of the main house).
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