What is permitted development?
Permitted development – or officially General Permitted Development Order (GDPO) – allows you to carry out certain minor alterations or building projects without needing any planning permission. However, some permitted development projects will require a prior approval application (see below).
If you want to be certain that your proposal falls within permitted development guidelines, you can apply for a certificate of lawful development. This may come in useful when you come to sell your property, to show the buyer that the work is legal.
Image above by James, architect in Bristol. See his full profile on Design for Me and shortlist him for your home project here.
What is a prior approval application?
A prior approval application will be needed in some circumstances for permitted development. It should be more straightforward and simpler compared to a planning application. However, it can be more rigid in terms of its grounds for approval or failure – there is less room for subjectivity and opinion than with a full planning application. This can work in your favour in terms of speed and simplicity, but at other times it might inhibit the design potential. It’s worth having a conversation with your architect about which would be the best route for your project.
Do you need any permission at all under permitted development?
Yes, the majority of building projects will require Building Control approval.
The other common approvals you may need include:
- freeholder consent
- party wall award
- covenants in the title to your property which may mean you will require someone else’s agreement.
See our article regarding the above permissions for house extensions in more detail here.
Permitted development exceptions
Do any of the following apply to you? If so, your permitted development rights may be restricted or removed.
- Your property is not a house e.g. a flat, maisonette.
- Your house or any buildings contained within the boundary is listed.
- Your property is in a conservation area.
- Your property is in a protected area e.g, National Park, Area of Outstanding Natural Beauty, Norfolk or Suffolk Broads or World Heritage Site.
Permitted development rules for rear extensions
The permitted development rules were permanently relaxed in 2020, allowing you to build an extension without planning permission of up to six metres (or eight metres if your house is detached). Please note that for these larger extensions (beyond four and three metres respectively) you will need to submit a prior approval application and give notification under the Neighbour Consultation Scheme.
- Materials to be similar to the existing house.
- No verandas, balconies or raised platforms.
- Must not be taller than the existing house.
- The extension(s) should not take up more than half of the garden/outdoor space.
- A single storey extension can’t be more than four metres high. If the extension is within two metres of the property’s boundary, it can’t be more than three metres high
There are a few other restrictions that we go into more detail on here: How big can I build an extension without planning permission?.
Permitted development rules for loft conversions
Straight conversions, dormer extensions and hip-to-gable loft extensions can usually be undertaken under permitted development. Mansard roof extensions will require a planning application.
1. An extension beyond the plane of the existing roof slope of the principal elevation that fronts a highway is NOT permitted development.
2. Materials to be similar in appearance to the existing house.
3. Cannot extend up beyond the existing highest point of the house.
4. No verandas, balconies or raised platforms.
5. Any side-facing windows must be obscure glazed and non-opening unless the parts which can be opened are more than 1.7 metres above the floor of the room in which it is installed.
6. Must not exceed 40 cubic metres for terraced houses and 50 cubic metres for detached and semi-detached houses.
7. Roof extensions, apart from hip to gable ones, to be set back at least 20cm from the original eaves. The 20cm distance is measured along the roof plane (fig.1)
fig.1
There are a few other restrictions that we go into more detail on here: Permitted development rules for loft conversions.
Permitted development rules for garden rooms
- It must not contain sleeping accommodation.
- It must be single storey.
- Maximum eaves height of 2.5m.
There are a few other restrictions that we go into more detail on here: Permitted development rules for garden rooms
Permitted development rules for basement extensions
Significant excavation works are likely to require planning permission, but it will usually be possible dig down in an existing basement room to create additional headroom to make the space habitable. For example, if your cellar is 1.5 metres, it should usually be permissible to increase it to 2.2 metres without requiring planning permission. However, you should always check this with your local council as they may have specific planning restrictions or compliance procedures relating to any excavation work.
There are a few other restrictions that we go into more detail on here: Permitted development rules for basement conversions.
Permitted development rules for a garage conversion
You wouldn’t usually need planning permission to convert your garage into additional living space, provided that the space won’t be used as a separate dwelling and the works are all internal.
There are a few other restrictions that we go in to more detail on here: Permitted development rules for shop to residential conversions.
Permitted development rules for shop to residential conversions
Class MA was introduced in 2021 and allows for Class E uses (e.g. shops) to be converted to residential use (C3).
Class MA is officially described as ‘commercial, business and service uses to dwellinghouses’.
- It applies in England.
- It must be strictly a conversion – no building up or outwards. There will be limitations too on the changes to external appearance – materials, windows, doors etc.
- The shop must have been vacant for at least three months prior to the prior approval application.
- The shop must have been operating as a shop (or other use in class E) for a continuous period of at least two years prior to the date of the prior approval application.
- The floorspace of the existing shop must not exceed 1,500 square metres.
- The prior approval application must meet certain criteria to be approved, for example:
- minimum space standards and light in habitable rooms;
- transport impacts, flood risks, contamination risks, noise impacts, impacts on the conservation area (where relevant), impact in relation to industry, waste management, storage, mixing uses, loss of certain services (nurseries, health centres), impact of local provision of the services lost.
There are a few other restrictions that we go into more detail on here: Permitted development rules for shop to residential conversions.
Permitted development rules for air source heat pumps
Here are the main rules for permitted development for air source heat pumps. For further detail see our full article here.
- It must comply with MCS or equivalent standards.
- Only one air source heat pump allowed at the property.
- You are not allowed to install an air source heat pump if the property already has a wind turbine.
- The outdoor unit cannot exceed 0.6 cubic metres.
- It cannot be installed within 1 metre of the boundary.
- It cannot be installed on a pitched roof or within 1m of the edge of a flat roof.
- It cannot be installed on a wall above the ground floor level if that wall fronts a highway.
Permitted development rules for solar panels
- The highest part of the solar PV or solar thermal equipment must be no higher than the highest part of the roof (excluding any chimney).
- The solar PV or solar thermal equipment must not protrude more than 0.2 metres beyond the plane of the wall or the roof slope when measured from the perpendicular with the external surface of the wall or roof slope.
- Solar panels that are stand-alone also benefit from permitted development.
For further details see our full article here.
Permitted development rules for a garden fence or wall
- A garden wall or fence should not exceed two metres (from ground level) without planning permission.
- However, if the wall in question fronts a highway (or footpath next to a highway), the wall or fence should not exceed one metre.
For further details see our full article here.
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