Do I need planning permission?

Getting planning permission for that dream extension or for essential maintenance can be a nightmare. Planning regulation is complex and many people have fallen into the pitfalls that await the ill-informed. As a starting point, we’ve distilled some key facts about what building projects do and don’t need planning permission and how to go about getting planning permission if you need it.

Angela Kerr Director, Editor

If you want to build something new or make a major change to your home you will probably need planning permission. If your project needs planning permission and you do the work without getting it, you can be served an enforcement notice ordering you to undo all the changes you have made. So don’t risk it and check which projects need planning permission before you start.

Do I need planning permission for an extension?

If you’re planning work to your home you’ll want to know ‘Do I need planning permission for an extension?’ An addition or extension to your house* is generally considered to be permitted development.

So, you won’t need to go through the additional hassle of getting planning permission for an extension as long as:

• Your extension is no more than half the area of land around the original house (curtilage). The “original house” is seen as it was in 1948; after this date how it was newly built
• Your extension is not forward of the principal elevation or side elevation onto a highway
• Your extension is not higher than the highest part of the roof
• In the case of single storey extensions, it must not extend beyond the rear wall of the original house by more than eight metres for a detached house, or more then six metres for any other house
• The maximum height of your single-storey rear extension is not higher than four metres
• Extensions of more than one storey do not extend beyond the rear wall of the original house by more than three metres
• Side extensions are single storey with maximum height of four metres and width no more than half that of the original house
• Two-storey extensions are no closer than seven metres to rear boundary
• The materials are similar in appearance to the existing house
• Your extension does not include verandas, balconies or raised platforms
• Any upper-floor, side-facing windows are obscure-glazed; any opening is 1.7m above the floor

When it comes to extension planning permission, conservatories are categorised as the same as any other extension, as set out above.

*Different rules regarding extension planning permission apply to flats and maisonettes.

There are also different planning restrictions for designated areas such as Conservation Areas and if your property is listed. So check with your Local Planning Authority.

You may be wondering if you need an architect for your extension project. An architect can be invaluable in successfully navigating the local planning authority. A planning consultant or a structural engineer can also help.

Do I need planning permission for a garage conversion?

In most cases, garage conversions can be completed under permitted development rights, especially if you aren’t intending to alter the structure of the building. However, ensure you check that there are no planning conditions attached to the garage – such as that it has to remain as parking. You can do this by checking the deeds of the property. Find out more in our guide Garage conversion: Where do I start?

Internal alterations – when do I need planning permission?

Nearly all internal works such as loft conversions, garage conversions, new staircases, bathroom refurbishment, kitchen renovation, or rewiring, do not require planning permission. But, do check if you want to do anything to a listed property or you live within a Conservation area. You may wish to get advice from an architect on your designs and they can help to navigate local planning requirements.

How to get planning permission

According to our recent Annual HomeOwner Survey, 27% of homeowners said getting planning permission for their house extension was a major obstacle to getting home renovations done. So how do you ensure problems with planning permission don’t put a stop to your plans?

Unless you already have a local architect designing and submitting your plans, and one with a track record of obtaining house extension planning permission in your area, a good planning consultant can be helpful in determining local planning restrictions, targets and preferences to ensure your project is tailored accordingly. They can help you to get planning permission.

An architect will often assist with drawing up plans and with the planning permission process. Find a local architect to discuss your project.

They may suggest you start with an informal meeting with your local planning authority (LPA) before you submit an application. Some local planning authorities charge for this service. A pre-planning application meeting helps you understand any concerns the LPA might have and gives them a heads up that your planning application is on the way.

Ahead of the LPA meeting, you will need to have proposals and plans of what you want to do.  Be ready to describe your proposals and if possible show the LPA designs – with current floor plans and elevations and the proposed changes. 

According to the Planning Portal it’s a good idea at this meeting to:

• Ask for an assessment of whether there is a reasonable chance of getting planning permission.
• Discuss site problems such as roads, footpaths, power cables, watercourses, sewers and telephone lines.
• Ask about potential problems such as noise and traffic, and whether the council might impose conditions to overcome these problems rather than refuse planning permission.

Planning application drawings

A key point in the process of getting planning permission is creating your design drawings. Whether it’s a small straightforward single storey extension on the back of your house, or something more ambitious, you will need a set of accurate floor plans for your designs and elevations (which show the vertical view of your design internally and externally).

These drawings need to be to scale and demonstrate how your project is in keeping with its surroundings. You can do the design drawings yourself or use a local architect’s firm that specialises in obtaining planning permission. Use our free tool to find local architects and architectural technicians who can assist with drawings for your planning application.

As well as your designs, you are likely to need technical drawings in order to get building regulations approval (see below) and for your builder. These provide in depth plans for each element of your project and materials that should be used. A structural engineer can look at your existing and proposed plans and advise on the building materials required and whether any reinforcements are needed and if so where. They can also produce the technical drawings you will need.

You can find structural engineers who cover your local area, obtain their details and compare their prices.

Applying for planning permission

When you’re ready, you can submit your plans for approval online. Most planning applications are submitted online. You can apply to every local authority in England through the Planning Portal or submit an application to an authority in Wales using your Planning Portal login details by visiting Planning Applications Wales.

After you’ve applied for planning permission

Once you’ve contacted your local planning authority (LPA) and applied via the Planning Portal website, the LPA will decide whether to grant planning permission for your project based on its local planning rules and development plan for the local area. Obtaining planning permission for an extension should be straight forward if you have followed local planning guidance.

How long does it take to get planning permission?

In most cases, planning applications are decided within 8 weeks. If the decision takes longer, you can appeal. And if you are refused permission you may want to appeal. Read our guide on what to do if planning permission is refused.

Planning permission for garages, sheds and other outbuildings

Outbuildings such as sheds, garages, greenhouses and some other structures like garden rooms are also considered to fall within permitted development rules so will not require planning permission. Under permitted development rules, you can build an outbuilding or garage without planning permission as long as it’s of a reasonable size – no higher than 4 metres.

If you’re asking how big can an outbuilding be without planning permission, do bear in mind though that outbuildings cannot take up more than half of the land around the original property.

However, there are always exceptions so contact your Local Planning Authority or visit the Planning Portal for further details of planning exemptions for garages and outbuildings.

Paving over the front garden: Do I need planning permission?

As long as the material you are using is porous there is no need for planning permission whatever the size of the new hardstanding. However, if the material is impermeable, anything over 5 square metres requires planning permission. Examples of permeable or porous surfacing which allows water to drain through it include gravel, permeable concrete block paving or porous asphalt. Equally, it is permissible if the surface slopes to allow rainwater to move in the direction of a lawn or border and can drain naturally.

But planning permission is required if you want to lay a non-permeable material, such as a stone or concrete driveway that is more than 5 square metres.

Planning permission for windows and doors

In most cases there is no need for planning permission to repair or replace windows and doors with those of a similar appearance. Building regulation approval is required on any glazing replacement work or you can use a registered installer (a FENSA accredited firm for example) to complete approved work for you.

Listed properties are the exception. In this case, you will have to obtain listed building consent as well as sign-off from your local Building Control team.

You will need planning permission if you’re fitting a skylight that protrudes more than 150mm beyond the plane of the roof slope or if it is higher than the highest point of the roof. You will also need planning permission if fitting an upper-floor side elevation window that is not obscure-glazed and can open (unless the opening part is 1.7 metres from the floor of the room).

Find a local planning consultant near you to help with your planning application

External walls and roof

For minor exterior maintenance works, or improvements such as painting your house, you do not need planning permission. As always this is not the case for listed buildings. If you live in a conservation area or an area of outstanding natural beauty, you need planning permission if you wish to change the exterior appearance of your home.

Cladding may be carried out without having to apply for planning permission as long as the materials are of a similar appearance to those used on the existing house.

If you live in a flat and you wish to alter the walls or roof you should consult the local planning authority before you start any work, as well as your freeholder/landlord.

Planning permission solar panels and wind turbines

Temporary wind turbines do not require planning permission but permanent ones usually do. If you are unsure contact your local authority.

Solar panels do not require planning permission unless you live in a listed property. And you must meet the limits and conditions set out under permitted development rights.

Fences, gates, and walls

Planning permission is necessary for any fence, gate, or wall:

• Next to a road and over 1 metre high
• Over 2 metres and not next to a road
• If your house is listed
• If it forms a boundary with a listed building

Trees and hedges

Many trees are protected by tree preservation orders and you will need permission to prune them. Contact your council to check if any trees on your land are protected.

Similarly, you need planning permission for work done to any trees in conservation areas. To find out if a tree on your property is protected contact your local council.

Hedges can be any height but you are responsible for any hedge on your property. It’s your job to stop them becoming a nuisance to your neighbours.

Can I build a house in my garden?

If you have enough land, you may be asking can I build a house in my garden. If you’re planning to build a self-contained property, then there are lots of steps you’ll need to take including getting planning permission. Your first step will likely to be to scope the project with an architect. See key questions to ask an architect.

Do I need building regulations as well?

Whether you need planning permission or not, your building work still needs to comply with building regulations. This is for your safety, to improve the energy efficiency of your home (and reduce bills) and to ensure you can sell your house in future without any costly problems or delays.

Make it clear to whoever carries out your building work that you expect them to ensure their work is compliant with building regulations. But, be warned: the building owner is ultimately responsible. You can be served a notice to pull down or alter the work if it doesn’t comply with the building regulations.

As a quick guide, building regulation applications are needed for most construction projects including:

New buildings

• All new buildings except agricultural buildings
• Garages that are not fully detached and under 30 square metres

Extensions

• All extensions no matter how small
• Some conservatories and porches (many are exempt but these must be separated from the house by doors and can’t be heated)
• Roof extensions, balconies and roof terraces
• Basements and basement extensions

You can apply for Building Regs approval at the same time or separately from your planning application using the Planning Portal website.

Find out more about this in our guide Do I need Building Regulations Approval?

Do I need a party wall agreement?

You also need to be aware that if you have a shared wall (party wall) with your neighbour, you may require a party wall agreement. Party Wall Agreements are most commonly needed for building works that involve loft conversions, the insertion of damp proof courses and the digging of new foundations (as would be required in building an extension). This falls outside of the planning system, but is a common pitfall that a lot of people only realise late on in the process. Read our guide to Party Wall Agreements.

Frequently Asked Questions