UK Planning Laws: Domestic Wooden Garden Structures, Gazebos, Pergolas & Carports

One of the questions were asked frequently is 'Do I Need Planning Permission?' In this post we will cover what we know through our 15+ years experiance of dealing with planning requirements, along with an explanation of the current National Guidelines, we hope we can steer you in the right direction with a basic, informed approach - we detail at the end a great checklist and 'what to do next' to help you proceed with your project in a more informed manner.

Many view planning regulations as an uneccessary obstruction, some even choose to ignore it completely. we have to remember that planning control is exactly that, its not there to stop you from building your dreams its there to make sure that everyone has a fair oppourtunity to build or extend with something that fits in the local community, that it applies equally to your neighbours as it does to you. So wether you are a looking to check if you need to gain permission or would rather the risk it and seek forgiveness afterwards approach, read on and we may be able to help inform you or guide you in your endeavours.

Every County and Council in the UK has different planning guidelines specific to their 'local plan'. The UK is divided up into regions and each region has its own Local Planning Authority (LPA) there role is to manage and control developments and additions to ensure they fall within national and local planning laws.

Most wooden garden structures on domestic properties in the UK fall under Permitted Development Rights (PDR), meaning they don't require formal planning permission if they meet specific criteria. It doesnt mean you can build what you want in your back garden, but it does mean that you can if you stay within the rules, if you go beyond the rules, recent legislative changes in 2024 have significantly altered enforcement timelines, and strict size, height, and location restrictions apply.

Primary Legislation

The UK Planning Laws are are subject to the Town and Country Planning Act 1990 - Core Planning Framework, its a big read but the main sections relevant to Garden Buildings and Wooden Structures are: General Permitted Development Order (GPDO) - Which defines permitted development rights, these are the developments (constructions and alterations) that you are abe to do without seeking permission, permitted development is also reffered to as "Lawful Development" and within the framework Class E Permitted Development specifically covers outbuildings and incidental structures such as Gazebos, Pergolas, Outdoor Kitchens. Dining Areas, Garden Offices, Carports and the alike

Temporary Structures - The Urban Myth

It is often quoted to us that the installation is a 'Temporary Structure' as its made out of wood and doesnt need planning consent - this is an urban myth, Temporary Structures are such as a Marquee for a party or a pop-up tent put up in the back garden for the weekend, or it may be a short term Storage Facility during building works, or a Portable Cabin etc, Temporary refers to a use of 28 days or less and is for facilities that require little or no groundworks, foundations and are built in an easily constructed and deconstructed method. - If you intend your Structure to be used for a prolonged period of time or year upon year then its not "Temporary"

Grandfather Rights

Grandfather Rights in planning refer to the historical legislation in place when something was originally built. there is a common misconstruction that because something is there for a period of time then its all 'ok'

i.e. a now derelict ruin of shed that was built at the bottom of your garden in the 1930's made with brick walls and a tin roof, it didnt need planning permission at the time as there was no planning law to cover it, it doesnt necessarily mean you can demolish it now and build a garden office there without planning permission. - It is probable that you would be able to replace the original with something of a similar size, shape and feel but you may need to make a formal application if the structure exceeds permitted development sizes.

4 Year Rule (Now 10 Year in England)

This bares no influence on any new projects you may be looking at in your garden, as they are yet to be built. However, the other side to what some people refer to as "Grandfather Rights" is the '4 year rule' in terms of unauthorised developments, this rule basically allows for a development (Structure) that has been in place for period of 4 years without any formal objections to its legal development (or previous planning refusal) being retropectively deemed legal.

As of April 25, 2024, a major change came into effect for England (Wales retains previous 4 year rules). A new 10-year rule replaced the previous 4-year rule for unauthorized developments, The 10 year rule allows an outbuilding to become lawful if it has been constructed and used continuously without enforcement action.

What are the Permitted Development Rights for Wooden Garden Structures?

So from the national guidlines as referred to in the Primary Legislation section, Size and Volume Restrictions Wooden outbuildings qualify as permitted development if they don't exceed 50% of the Original Curtilage Area around the original house. This in basic terms is the area of the entire property, garden, driveway etc, minus (-) the area of the house and outbuildings as when first built or as of 1st July 1948 (whichever is soonest), this is 'The Original Curtilage Area' so Divided by 2 - this number represents the maximum size in total (cumulative) of Outbuildings permissable subject to individual building footprints (this is typically 30m² but can be 15m² for smaller properties or properties with restrictive covenants) I.e. your house and attached garage have a footprint of 150m² sat on a property who's boundaries extend to 200m² therefore your curtilage is 50m² and the maximum total size of any outbuildings would be 25m²

With our maximum size of structure calculated our next consideration needs to be Height Restrictions, these are Critical Height limits that must not be exceeded. In Standard terms the Maximum eaves (the part where the vertical side ends and the roof starts) height of 2.5 metres and maximum overall height of 4 metres with a dual pitched roof (Hipped or Multifaceted) or 3 metres for any other roof (Gable End, Flat Roof or Single Pitch, if the construction is a single-story 'Shed' (depicted as all four sides enclosed and a closing door) it should not exceed 2.5 metres in height. A contentious point is where the height is measured from (Datum), this is always from the base or floor level, and in terms of a concrete base or slabbed / tiled area it is from the top of this base, decking doesnt count and the height of the decking from the base is included within the height restrictions. Also in terms of sloping land, infil or 'making up' of the surface is not excluded from the height restriction either, if you have made up land to create a level base the height datum will be taken from the average of the initial surface level. It is also worth noting that if the main property on the site is a Bungalow or Chalet Style property with Low Level Eaves then the eaves of the structure shouldn't exceed the height of the main property.

Boundary Proximity Rules again a sometimes a contentious point, always make sure you are 100% certain of where your boundary lies, you must posistion your structure within your boundary if you intend to attach to a neighbours wall or build with the side of your structure representing the fence or boundary line then a 'Part Wall Agreement' should be undertaken. If your building within 2m of the boundary the Maximum Height of 2.5 metres is within the permitted development guidelines, outside of 2m from the boundary the standard Height Restricitions guidelines apply as previously described.

Prohibited Locations in terms of standard permitted development;

No outbuilding on land forward of a wall forming the principal elevation of the main property facing the highway. This means you won't have permitted development to erect a shed in your front garden next to the road. - Planning application required.
Cannot obstruct public rights of way. If you have any footpath, bridleway or accesway to other properties within your boundaries, you cannot place your structure accross them.
Must remain within property boundaries.

Permitted Locations in terms of standard permitted development

Rear gardens (most common and least restrictive)
Side gardens (subject to boundary height restrictions)
The building must be located within the property's boundary and not obstruct any rights of way or cause an inconvenience.

So we have decided what we are building, where we can build it and what heights and size we are allowed within usual permitted development, our next consideration is Permitted Use - surely you can use a building in your garden for whatever you want? Unfortunately not, the good news is you probably can use your structure / building for what you wanted it for, domestic storage, a hobby room, personal home gym, outdoor dining area, garden shed, home office for remote work the list is extensive. What you cannot use it for (without planning consent) is for a seperate dwelling residential or even an 'annex' so if you were planning on putting in a kitchen, bathroom and a toilet then dont without planning permission, this type of building however large also needs Building Regulations, an area we will cover a bit further down the page. If the building is intended for the primary office for your business or for commercial operations (those being ones that attract business rates) then it will also need planning consent.

Exemptions and Special Circumstances to Permitted Development Rights

So you've covered off everything that you need to build your structure, size, height, position, use. What else must you consider? Well in the main it is the building or house itself, and where the property is located. If your property is Listed or subject to an Article 4 Direction (which removes certain PDRs), you will need planning permission for any outbuildings or at least to seek a "Lawful Development Certificate" which states that planning permission wasn't required, other areas such as Conservation areas may have Article 4 directions these are usually specified by a conservation boundary, and have particular rules to each conservation area depicting whats permissable within view of public areas such as highways, footpaths and areas that are publically accessible, the Article 4 Directions are also usually applicable in National Parks, Areas of Outstanding Natural Beauty (AONB) and Sites of Special Scientific Interest (SSSI) although national guidelines apply, these can also have there own Local Planning Authority (LPA) which sets guidelines and recieves planning applications seperate to the main regional LPA

The other consideration is Covenants, as well as any Previous Developments at the property, if additions and extensions that have have already been constructed exceed the size thesholds and allowances as previously mentioned you may have already reached the permitted development threshold. Previous planning permissions that had been granted at the property may have come with conditions about further developments or constructuons, also please do check your Title Deeds these may contain a restrictive covenant preventing the building of outbuildings etc. These can be commonplace on large modern estates where the developers would wish to restrict the contruction of anything outside of there original plan or vision prior to completion of the construction, if you do have these, they are often for a set time period or easily removed by a property solicitor should you require it - so its important to research the history of your property in these terms. Finally any construction that you intend to build that requires significant groundworks (excavations) or foundations would automatically require permission.

Building Regulations vs Planning Permission

Many of our clients ask about Building Regulations and there significance, in short Building Regulations Apply When the floor area exceeds 30m², or if the building will include a form of plumbing or heating system, or will have sleeping accomodation, as mentioned earlier if the building is intended as domestic accomodation, it doesnt matter how big it is it will need planning permission and building regulation approval.

Why & What's Needed

It makes sense that if a building is large +30m² then it needs to be structuraly capable of holding itself up, the build itself and its foundation is able to support a defined load or force that may be exerted on it (Rain, Snow, Wind) for the safety of those inside it, but also for any insurance requirements that you may have on it (Carports, Outdoor Kitchens etc). If the building has a heating source, it needs to be insulated to the correct standards for heated spaces and also that adequate ventilation is provided, that fire safety provisions are provided for buildings with independant power (please note a circuit extension off the main house fuse board for a light in your shed is not considered as independant, but this should be installed and certificated by a competant person) or sleeping accomodation, remember these regulations are there to provide protection to the end consumer.

Be Informed

Remember, planning control and building regulations are there to ensure that building and development is kept to guidelines. They are not there to prevent you from doing something you are allowed to do, they will approve constructions if you are, but they will disprove of things that are not. It is the homeowners responsibilty to ensure that everything is correct. We always suggust a bit of local detective work, specifically for larger projects such as garden rooms or carports, if you have seen one in the local area look up the address on planning portals or your LPA website, all historic planning applications are stored digitally from the 1990's onwards so it can give you a great insight into who needed planning for what, any restrictions or conditions that were placed on designs etc, it can give a good reflection of what you may need in terms of your own project. If in doubt, seek assistance - help and support is always available from reputable contractors, design engineers etc.

Due Diligence Checklist

We mentioned earlier a 'Checklist' on what to consider in your project to add a structure or outbuilding at your property.

Boundary Location & Disputes - Always verify boundary locations with title deeds
Restrictions, Covenants and Article 4 Directions - Know your property 'Listed' status, the local area and read your title deeds to note any covenants, rights of way or any footpaths or wayleaves for services.
Calculate Cumulative Development - Check against your original curtilage and apply the 50% rule including your planned additions.
Measure Precisely - Make sure you can fit in what you want to achieve, last minute changes can often prove costly.
Design - Make a Clear Plan or Sketch of the structure, it doesnt need to be perfect, just show size, height and proximity to boundary. - if you do need to apply for permission a scaled accurate representation will be needed.
Find Similar Examples - Finding images online of structures you want to emulate, even if its a jigsaw of images, roof of this, wall of that etc - it all helps to convey the design and the aesthetic better than a 2D drawing.
Document Intended Use - This is simply making sure any plans or design you draw up state 'Garden Room' or 'Outdoor Dining Area' so there is no querying what your use of the space is. This will also help you determine if you need Building Regulations.
Take Photos of Exisiting Site - This will aid you to show the history of the site, share the work area with any contractors prior to a physical inspection and to show how the height datum was historically taken.
Inform Your Neighbours - A short conversation with your boundary neighbours about your intended project removes the suprise, it also removes the majority of potential complaints to the LPA even if you have permitted development rights they will still investigate and this could cause disruption to your plans.
Check your local Area - Search online through planning portals and LPA websites to see if neighbouring properties needed planning consent to achieve similar projects.
Allow Enough Time - Projects take time, if your planning your project for a special occasion be realistic on timescales to check or obtain permission and construction timescales, good contractors are busy. Allowing enough time prevents stressful situations and improves the satisfaction of the overall outcome.

What if I do Need Planning!!?

Don't panic! in our experiance the main of planning applications are approved as long as you stay sensible in what you are trying to achieve, yes a structure that covers your whole rear garden will not get planning, but if you keep within guidelines the application for the outdoor kitchen thats 10% above size limitations will probably be ok, remember that planning is about control within limitations, its not there to stop everything.

So if you have concluded that you do need planning, then follow the simple steps provided by services such as 'The Planning Portal' they provide a great service to assist in making sure your application is compliant, you will need accurate plans of the design showing elevations in 1:100 or 1:200 scale, dimensioned always helps and details of constuction materials - remember to state the purpose on the application and the design. A title plan showing position and proximity to boundary, as well as a block plan showing the local area. These are usually available online through Ordinance Survey or Standfords as well as other mapping companies.

If you're unsure and/or you want to check formally if you do need planning, our reccomendation to our clients is to submit a 'Do I need Planning' application to your LPA. This service is available through the LPA's website, it also requires a form of scaled dimensioned design, location plan and details on the purpose of construction and its finished materials, you will get a response back from the LPA confirming that you either need to submit a formal planning applcation or that your construction is within permitted development if constructed to the size and purpose.

Applications of any type to the LPA take time, realistically allow 12-15 weeks for formal planning and 10 weeks for informal, local authorities are very busy so it may take a while for your application to be considered and accepted, formal planning applications require a 21 day notice period to your local area to ensure neighbouring properties are informed of your application and given the opportunity to comment on it formally to the LPA.

Hampshire Garden Structures offer guideance and assistance with UK planning and building regulations for our clients, plans are available for them to help in enquiries and applications. If you're within our catchment area and are planning a wooden construction project we would be pleased to look at it for you, design through to construction.

Even if you're not in catchment we hope this helps someone out there, even if your not one of our clients or future clients.