Not all changes or improvements to your home need permission from the planning department. There are many that you can carry out with implied consent, known as Permitted Development. It is well worth being aware of these rights, and recent changes to the rules, if you want to make any significant home improvements. It could save you time and money!

What is Permitted Development?

Permitted Development (PD) grants rights to enable homeowners to undertake certain types of work without the need to apply for planning permission. There are many innovative opportunities whereby PD rights can bring significant benefits to anyone who wants to undertake a project to improve their existing home or is looking to maximise the potential of a new investment.

To take advantage of PD you need to fully understand what is involved and the criteria — as well as stay up to date with all the latest changes.

This implied consent of Permitted Development is granted in the form of General Development Planning Orders (GDPOs) which apply separately to England, Wales, Scotland and Northern Ireland.

Do double check with your local authority or get confirmation from a qualified surveyor that your proposed works are classed as Permitted Development before you begin. It may be beneficial to submit a prior notification application.

If you need to apply for planning permission, check out our complete guide to what the process involves.

Do I Have Permitted Development Rights?

Barn converted and extended under Permitted Deevelopment

Natalie Davies and Mark Hills were able to convert a barn on their property and link it to their existing home under PD rights, though they did receive a Lawful Development Certificate from their local authority to ensure that there could be no further redress

Most likely yes, but there are a few things to bear in mind. Unfortunately, the slate is not wiped clean when you buy a home — any space added by past owners since 1948 counts towards your Permitted Development allocation.

If your house is located in a Designated Area, such as a National Park, Area of Outstanding Natural Beauty or Conservation Area then your Permitted Development rights may be restricted or removed under what is known as an Article 4 direction. This is where rights have been removed in the interest of maintaining the character of the local area. This could also be the case if your property is listed.

Alternatively, if you’re planning to self build a replacement dwelling and your proposed new home is bigger than the existing house on site, then your Permitted Development rights are likely to be restricted or even removed on condition of granting planning permission.

Remember than all Permitted Development requirements apply to the dwelling as it was originally built, or as it stood on 1st July 1948.

PD Rights do not apply to flats or maisonettes due to the impact that any alterations could have on neighbouring properties.

Changes to Permitted Development Rights in 2019

All planning legislation changes, and Permitted Development and Prior Notification is no exception. Revisions stem fro the relaxation of regulations in 2012 which encouraged development and helped to take the pressure off planning departments processing applications.

One of the key changes in the May 2019 regulations is that the new order makes it clear that the regulations make permanent the right to build larger rear single-storey extensions under Class A. This means it is now possible to build the larger extensions subject to the prior approval process without fear of their previously temporary provision expiring.

Types of Permitted Development Rights

Householder PD rights fall into different categories depending on the work being planned. These are:

Class A – Extensions (enlargement, improvement or alteration)

This allows a householder to build a single-storey side extension up to half the width of the existing dwelling; a single-storey rear extension up to 4m in length for a detached dwelling and 3m long for a semi or a terrace house; and, in certain circumstances, 3m two-storey rear extensions.

The changes that took effect on 30 May 2019 now make permanent the decision that larger single-storey rear extensions of up to 8m (6m for semi or terrace) are permissible under Class A — but do require prior notification (see ‘Lawful Development Certificates are key’).

Class B – Additions to the roof

This allows for rear dormers and hip-to-gable extensions as long as the additional volume created does not exceed 50m3 (40m3 for semis and terraced homes).

Class C – Other alterations to the roof

Class D – Porches

Class E – Buildings etc. (outbuildings)

This allows for an outbuilding to be erected within a residential curtilage as long as it is sited behind the principal (often the front) elevation, does not cover more than 50% of the curtilage and is not more than 3m in height (4m for a dual-pitched roof; 2.5m where within 2m of a boundary).

There are also specific regulations relating to Hard Surfaces (Class F), Chimneys & Flues (Class G) and Microwave antennas (Class H).

Is Prior Notification the Same as Permitted Development?

Hip-to-gable loft extension was achievable under permitted development while the two-storey rear extension required planning permission

This remodel of a terrace London home designed by Selencky///Parsons had a two-stage plan: a two-storey extension that fell outside the remit of PD, and a hip-to-gable loft extension that was achievable under PD rights. Image: Siobhan Doran c/o Selencky///Parsons

Prior notification is a form of Permitted Development whereby the local planning authority must be notified of the details prior to development taking place. Although prior notification is a form of PD, the process is a lot more involved and the local planning authority (LPA) has a lot more say in comparison with a PD application.

With a PD application, the regulations are explicit and it is normally pretty clear cut as to whether a proposed scheme complied with the regulations or not. However, under a prior notification application, the LPA often has the opportunity to determine whether they consider the proposal to constitute conversion as opposed to rebuilding, whether the materials used are appropriate, whether the proposal would be broadly in line with the objectives of the National Planning Policy Framework, and whether there might be other associated impacts such as contamination, noise, flooding etc.

However, these rules do allow for a number of projects to be completed without planning permission.

For householders, single storey, rear residential extensions can be built up to 8m in depth (6m for a semi or terrace) provided that boundary neighbours are first informed. If no objections are received (or any objections received are not considered to have planning merit) and the LPA is satisfied that there are no significant adverse impacts arising from flooding, highways or contamination, a Lawful Development Certificate is issued.

Prior notification can also be used to change the use of non-residential buildings to residential purposes. It can be used to change buildings from one commercial use to another, too.

Converting Commercial and Agricultural Buildings

A1 (shops), A2 (professional and financial services) and A5 (hot food takeaways) may be converted to residential (up to 150m²). The LPA may consider the design of the associated physical development to ensure it complies with the Local Plan and the potential impact of the loss of the A1/A2 use on the economic health of the town centre.

Agricultural buildings may be converted to residential (up to 450m²), as long as the building is structurally capable of being converted without requiring engineering work and providing access can be achieved. Up to five dwellings may be created up to a maximum floorspace of 465m², of which three may be ‘large’ (>100m²). This change of use is subject to prior approval being sought in respect of:

  • transport and highways impacts
  • noise impact
  • contamination risks
  • flooding risks
  • location or siting
  • the design or external appearance of the building

B1c (light industrial) and B8 (storage) buildings may be converted to residential as long as the gross floor space of the existing building does not exceed 500m². Again, the LPA may assess the highways, contamination, flooding and economic impacts and risks associated with the proposal.

Permitted Development and Lawful Development Certificates

In theory, if a proposal constitutes Permitted Development and is fully compliant with the regulations, no application is required.

However, if you’re not going down the prior notification process, it is extremely advisable to apply for a Certificate of Lawful Proposed Use or Development, otherwise known as a Lawful Development Certificate (LDC), to ensure that your proposal complies with the regulations and that you will not be faced with difficulties post construction.

If, once an extension or outbuilding etc. is constructed, the LPA determines that the proposal does not comply with PD regulations then you may be faced with enforcement action, which would normally result in a request for a retrospective application. Should permission be refused there is a real likelihood that any extensions or associated works would be required to be demolished. As such, confirmation in the form of the LDC is highly recommended.

The legislation is not the easiest to interpret, so take a look at the Planning Portal which is a useful resource in helping to find out what is covered within these rights. There is an option to select England or Wales, so depending on where your property is you can select the appropriate country for the relevant regulations.

An old conservatory was replaced by a single storey extension under Permitted Development

An old conservatory was knocked down and a single-storey extension to the rear of the house was added under Permitted Development. Image: Jody Stewart

How Big Can an Extension be Under Permitted Development?

Under the rules, the ‘original’ (as it stood in or prior to 1948) rear wall of a detached home can be extended (subject to the neighbour consultation scheme) by up to 8m in depth with a single storey extension; this is reduced to 6m if you live in a semi or terrace. If your proposed new extension will be within 2m of a boundary, then the eaves height is limited to 3m under Permitted Development. Otherwise, a single storey rear extensions must be no higher than 4m.

If you hope to build a two storey extension (no higher than the house), this can project up to 3m from the original rear wall, so long as it is at least 7m from the rear boundary. It’s also important to note that no extension can project beyond or be added to what is deemed to be the front of the house or an elevation which affronts the highway. And a side extension can not make up more than half your house’s width.

Furthermore, with the exception of conservatories, new extensions must be built of materials ‘similar in appearance’ and with the same roof pitch as the main house. So while Permitted Development rights are beneficial, there’s a lot to consider before starting work.

Permitted Development Rules for Extensions

  • You can extend a detached dwelling by 8m to the rear if it’s single storey or 3m if it’s double
  • Semi-detached and terraced homes can be extended up to 6m to the rear of the property if single storey
  • There are height restrictions but they boil down to a single storey extension not being higher than 4m in height to the ridge and the eaves, and ridge heights of any extension not being higher than the existing property
  • Two storey extensions must not be closer than 7m to the rear boundary
  • It must be built in the same or similar material to the existing dwelling
  • Extensions must not go forward of the building line of the original dwelling
  • Side extensions must be single storey, maximum height of 4m and a width no more than half of the original building
  • In Designated Areas side extensions require planning permission and all rear extensions must be single storey
  • An extension must not result in more than half the garden being covered
  • You can only do it once and the original building is either as it was on 1st July 1948 or when it was built. In Northern Ireland it is as it was built or as it was on 1st October 1973

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Could I Both Extend My Home and Convert My Loft Under Permitted Development?

In the past, volume limitations were applied to the entire house — so if you extended, you were unlikely to be able to convert your loft under Permitted Development rights as well. The good news is that the latter has now been separated out, allowing you to undertake both without one restricting the other.

So, you can also convert your loft into a bedroom or extra living space by up to 50m³ in a detached house, or by 40m³ within any other home. Flush rooflights or those which do not project further than 150mm are permitted, but you will need permission to add a dormer window on any roof elevation which faces the highway.

However, you cannot cover more than 50% of the land around your house with extensions (including extensions by previous owners), and you have to include any outbuildings when calculating this coverage. Sheds and other outbuildings count in this calculation.

What Improvements Can I Make Within Permitted Development?

The scope of your Permitted Development rights are varied and cover both internal and external works, but there are strict design criteria that need to be adhered to. If your project falls outside of the set criteria, then it is likely you will need to submit a planning application.

Some home improvements that you can make under Permitted Development include:

  • Building a porch
  • Internal alterations
  • Convert and occupy the loft space
  • Installing microgeneration equipment such as solar panels (apart from wind turbines)
  • Installing satellite dishes and erecting antenna
  • Adding rooflights or dormer windows
  • Extending the back of your home

(MORE: See 20 home improvements you can make under Permitted Development)

Are Outbuildings Covered by Permitted Development?

  • You can construct all sorts of outbuildings for the use and enjoyment of the home so long as they do not cover more than 50% of the garden space. In Scotland this is reduced to 30%
  • In Wales and Northern Ireland any outbuildings closer to the house than 5m count as extensions. In Scotland any outbuildings larger than 4m² and closer to the dwelling than 5m count as extensions
  • Outbuildings must be single storey with a maximum ridge height of 4m for a pitched roof or 3m for any other kind of roof. The eaves height must be no more than 2.5 metres
  • If the outbuilding is closer to the boundary than 2m it shall be no higher than 2.5m
  • No outbuilding can be forward of the original dwelling. In Wales and Northern Ireland the same applies unless the resulting building would be more than 20m from the road

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Can I Convert an Existing Building Under Permitted Development?

Under Permitted Development, existing buildings – such as offices, barns and other agricultural buildings – can be converted into homes.

Agricultural Buildings and Barn Conversions

In March 2013 a new system was introduced to allow the conversion of barns into dwellings. Permission would still be required via the prior approvals process, but it created potential for more conversion opportunities than before. Read more here.

Former Office Buildings

In an attempt to release inner-city land for housing, the next change in Permitted Development was an announcement in May 2013 to allow offices to be converted to residential. This was set to expire in 2016, but in October 2015 it was declared that these rights would be made permanent.

Permitted Development for Balconies and Driveways

  • Balconies, verandas and raised platforms (above 300mm) do not fall under Permitted Development rights
  • You will also now need planning permission to construct a drive from non-porous materials such as tarmac. But you can construct a new drive of porous materials, or non-porous if provision for drainage is provided on the property, under Permitted Development

For more details on the rules see the Planning Portal.

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  • Anonymous

    We are in the process of building a conservatory under PD. We had built some foundations as part of some other building work and then the conservatory supplier indicated that they thought we may need planning permission. We contacted the planning office who were not sure (unbelievably) but told us we had better apply just in case. The dimensions of the new build fit well within the PD guidelines so we were pretty sure it would be ok. Now the next door neighbour has objected on grounds of light,( as one of the walls is very close to the boundary fence) and the planning has been rejected! We could appeal or compromise our build and resubmit, but I would really like to understand if we can get a conservatory added to our house via permitted development or not. If yes, what would be dimensions/build need to be, as it is very ambiguous on the PD and planning portals site.
    Anyone got any advice?

  • Anonymous

    “The dimensions of the new build fit well within the PD guidelines so…”

    If that’s the case, then you should have been advised by the council to submit an application for a “Lawful Development Certificate” (LDC), not a planning application. The former is determined on the ‘lawfulness’ of the proposal considered against the provisions of Statutory Instrument 2008 No 2362 (Google that phrase); the later is determined on planning merits. The two are wholly different.

    You do not need the LDC for your conservatory to be lawful. The value of an LDC is that it proves ‘lawfulness’ rather than confering it(Handy when you want to sell the house; peace of mind in the meantime). Permitted development IS planning permission, granted by Parliament.

    What you came up against with the planners is common. Your experience is driven less by true ‘misunderstanding’ of the new PD rules by councils than the system itself being driven by neighbour complaints and the desire of planners to generate fee income and exercise discretionary control of the details of development. Its not the individual planning officer’s fault!

  • woolford

    We are considering building a movable timber frame building which I am told complies with caravan laws.
    Would this be OK as it includes sleeping accommodation.

  • Anonymous

    If you are building a new detached house, how quickly after the completion certificate has been issued could you add your permitted development?

  • MikeB

    I live in a Close which overlooks the rear of a row of semi-detached houses where the rear boundaries have always been defined by fences. One of the owners of the semi detached houses made a planning application for the erection of a garage at the rear of her property.This application was refused by the Council on the grounds that it would be detrimental to the amenity value of our Close and that it was not within the height limitations. The applcant changed the plans to reduce the height and the Council then treated it as a permitted development. The question is this – does the detrimental affect on our amenity value still apply even though the development is now permitted ? The amenity problem (view/vehicle movements in a small Close etc) does not disappear because a development is permitted. Does the amenity value issue supercede the permitted development ?

  • Miguel

    Hi all,

    I am confused on whether I have to apply for a planning permission or not. I need to remove the roof of my kitchen which is currently of asbestos, and put some wale slates. The rest of the house is on wale slates. The job will not involve any structural changes. It is basically, removing the asbestos and putting the slates. Will this fall into the permitted development category?
    Thanks for all the help


  • Anonymous

    I live in a council house and want to put a
    Conservatory on the back 5m
    Across and 3m out do I need planing permission
    Or can I just go ahead and build. It’s going
    To be dwarf brick wall then pvc frame and glass
    With flat roof ?????

  • redditch estate agents

    I would not risk any building projects if I lived in a council house! But I wouldnt want to spend money on something I didnt own anyway!

  • Anonymous

    My neighbour is planning a single storey side extension to their property under permitted development. They are abiding by all the rules however I wish to object because it will encroach towards my property whereas now there is a large gap between the two properties ie 12 feet and also the extension I feel would take away natural light from my side reception window. Also the velux windows will shine light into my upstairs bedroom window. Because it is all within PD rules how can I object, what are the best routes to go or is it tough and I have no rights to object and just have to put up with it?

  • phil brook

    Is there any regulation which prevents you increasing the size of a property by more than double. We are having trouble with LA as they are stating that the extension should be subservient to the main house. This would not however achieve what we want. We do have outline planning for a new property which is approximately 3500 feet square and the sketch plan for the extension is much less.

  • Samuel Joy

    Hi Phil,

    I would of thought that an extension of that size is unlikely to gain planning permission, however as the rules on Permitted Development have changed within the last few years it’s probably best to have a look at the planning portal website.

    Their guide to extensions is here

    Kind regards and all the best,
    Samuel Joy (Online Editor)

  • Anonymous

    Hello Samuel,

    I have observed that some people construct only the foundations of a building and leave them for years before they complete the building.
    I have subsequently heared that such building are given automatic planning consent after a specific number of years.

    Is this true ?

    Kind regards

  • Jason Orme


    Not true I’m afraid. Planning permissions have a time period before they lapse of either three or five years. A plotowner who hasn’t yet built will usually complete the foundations in order to have officially ‘commenced’ before the time period lapses. The building itself can then take as long as it needs to finish, with the planning permission having deemed to be satisfied.

    There is no such thing as automatic planning consent I’m afraid!

  • Curious

    I hav just purchased a three story maisonette in a victorian terrace with a flat roof terrace leading off the back on the hous. I want to add a conservatory with two full side walls and a glass roof and front over the area of the roof terrace (approx 6 sqm) but cant work out whether this wil fall within permitted development right. The roof terrace is the roof of the lower flat (not my property) and so I would in effect be building on their roof. I cant work out whether this needs planning consent or not and would be grateful for any ideas or thoughts!
    Thanks very much, Emilia

  • Mcflozza


    I had planning permission rejected for a side extension along with a loft conversion. I scaled down the extension and removed the loft conversion, resubmitted and have now received approval. There is no restriction within the approval in respect of future PD rights or loft conversion. I want to undertake the roof conversion under PD at the same time as the side extension but would appreciate some advice as to the legality of this being done concurrently, or indeed at all. Should I undertake the work and then seek a lawful development certificate, or do so beforehand?

    Best wishes and thanks in anticipation.

  • nancy shillito

    My neighbour ( who owns her property ) has a single ground floor extension on the rear of her property .
    We live in a small terrace of 3 and she is mid terrace and I am end of terrace .
    This window looks directly into my garden and my kitchen .
    I do not have any privacy at all and it feels so uncomfortable that I dont really put my garden to use .
    I have tried to move by mutual exchange but all people have declined because of this issue .
    I bought a pergola ( to cover with plants and for privacy ) and popped round to ask her if she objected to me putting it up , She does saying it will block her view !
    Is this window allowed to be clear glass as it does intrude on my privacy ?
    Can she be requested to make it opaque ?
    Can she object to me erecting my pergola as some kind of privacy screen ?

    Thanking all in advance for any advice given .

  • Samuel Joy

    Hi Nancy,

    I have reposted your question in the discussion forum as I believe you are more likely to receive a response there. The link to your question is

    Also, I thought this previous Q&A may be of some use

    Kind regards,
    Sam Joy (Online Editor)

  • Sam Harris


    We’re looking to build a side return extension and a rear extension on the back of the outrigger to make a large L shaped open plan kitchen. The dimensions fall within PD, but I’m confused by the ‘similar materials’ clause. I was hoping to put a glass roof on the side return would this be permitted or would I need planning? It is a victorian terrace – brick and slate.


  • mark

    I wonder how this will effect the new homes market.

  • r.simonytexx

    If i buy a pieace of land with a permission to build, what other documentation should i have? Building drawing and what else?

  • mcwc

    Am I permitted without planning permission to build a second outer wall to the side of our three bedded terrace home about 6 ft depth to create a hallway going along the side of our home. We would want to create a space for a door on existing wall as entrance to hallway. Presume a door would be required as exit and a window.

  • phaywain

    Hi When a detached bungalow is divided into 2 Simi detached bungalow down the middle under a planning application but is never registered within the title who determines the curtilage? of the property?

  • zandraslucky

    I have a house on a 3 acre rural site – all of which is in domestic curtilage. After a battle with planners for a small single storey extension, we now have no remaining permitted development rights for the house or any outbuildings. We would like to erect a small summer house in the garden – normally allowed within permitted development. If we erect this on a type one sub base as a temporary building, is this acceptable under current planning laws ? We have been advised by a small building company that this complies and that the planners cannot object – even though they have removed our PDRs.

  • jackiebigwood


    We live in an AONB area, have just got PD certificate for rear single story extension(not yet built). If we wanted to put a basement under this, we know we would have to go in for full permission, but would we lose the PD right for the rear extension?

  • mrandmrs_k

    I am new to this site, I have a question about a P D height, I know that it can’t be more than 3m to the eaves and 4m to the ridge but am trying to find where this is measured from. Is it the highest ground level from the existing house or the ground level at the new extension?
    In the rules it states “the ground level is the highest part of the surface of the ground next to the building”
    Any help would be appreciated Thanks

  • Isabella Bardswell

    Does anyone know whether the recent changes impact PD rules in conservation zones?

  • carrieann redfern

    Hi I have been looking at permitted development and believe that what we wish to do falls under this. Our house has a lean to at the back which is of poor quality. We want to remove this and turn it into a proper brick extension so that we can actually use the room. It’s only small and everything falls under permitted development from what myself and the builders can see. So what do we do next do we legally have to apply for anything, do we have to apply for the certificate, do we legally have to involve building control or can we just get on and build. I’m going round and round and getting rather confused

  • Lindsey profile picture
    Lindsey Davis

    Hi Carrieann,

    You will need to involve Building Control as you are making structural changes, so notify them of the works and they will assign an inspector to check up throughout the process. There will be a fee for this.

    It is also a good idea to apply for a certificate of lawful development as this will a) ensure that what you are doing is under PD, and b) be proof to future buyers that your work was within the law.


  • Richard Gurney

    Concurrent or Sequential use of Two or more permitted developments ?

    Would it be considered legal to use the PD of side extension of a property upto ½ of original building width and 4m height limit in conjunction with the 50m3 increase in the original property volume to allow change to the roof height to then allow building upto the original building ridge height of about 5m

    Would this have to be sequential with the 4m width first or could the 2 be built together

  • […] permitted development you can make improvements (such as small extensions or loft conversions) to your home without […]

  • Antony Atkins

    What about adding a basement under PD rights? I cannot see why adding a basement with the same or less than the original footprint of the house would not be OK, provided there were acceptable lighting and fire escape options, that any lightwells do not impinge on a neighbour, and building regulations generally were followed. But perhaps the planning rules would be different if the intention was to create a separate residential unit – perhaps as a lettable unit – rather than simply add extra space?

    The building regs would be different too, because if the basement included its own cooking facilities, ring main, sewerage etc, then there would need to be significant fire- and sound-proofing to separate the two residential units, just as with a block of flats.

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