Do i need Planning permission is one of the questions we’re asked most often at One More Room when it comes to garden rooms. We’ve put together some clear answers to help guide you through the essentials.

Do i need planning permission for a garden room in the UK?

In most cases, One More Room Garden Buildings do not require a formal planning application, as they are generally covered under permitted development rights (Class E). This legislation provides homeowners with a form of pre-approved planning permission, allowing additional buildings or structures within the boundary of a property without the need for a full application process.

However, permitted development is only valid if a garden building is designed and constructed within a specific set of limits and conditions. These conditions are in place to ensure that the building is appropriate for residential use, does not overpower the main property, and does not create issues for neighbouring homes. For example, rules can relate to overall height, distance from boundaries, the size of the building in relation to the garden, and whether the space will be used for accommodation.

At One More Room Garden Buildings, we design every project with these requirements in mind, combining precision, careful planning, and high-quality construction methods to help keep the process as straightforward as possible for our clients. While many of our garden rooms fall within permitted development and can therefore be installed without additional planning approval, we always advise checking with your local council for confirmation, as individual circumstances may vary.

By working with us, you gain peace of mind that your building is not only beautifully designed and built to last but also carefully considered to align with planning regulations wherever possible.

Essential points to note are:

  • That the garden room is no higher than 2.5m from the bottom of the building to the top of the roof (if within 2m of boundary)

  • That you do not take up more than 50% of your garden area with this or any other buildings

  • It is not to be used for living or sleeping accommodation

Outbuildings are considered to be permitted development, not needing planning permission, subject to the following limits and conditions:

  • No outbuilding on land forward of a wall forming the principal elevation.

  • Outbuildings and garages to be single storey with maximum eaves height of 2.5 metres and maximum overall height of four metres with a dual pitched roof or three metres for any other roof.

  • Maximum height of 2.5 metres in the case of a building, enclosure or container  within two metres of a boundary of the curtilage of the dwellinghouse.

  • No verandas, balconies or raised platforms.

  • No more than half the area of land around the “original house”* would be covered by additions or other buildings.

  • In National Parks, the Broads, Areas of Outstanding Natural Beauty and World Heritage Sites the maximum area to be covered by buildings, enclosures, containers and pools more than 20 metres from house to be limited to 10 square metres.

  • On designated land* buildings, enclosures, containers and pools at the side of properties will require planning permission.

  • Within the curtilage of listed buildings any outbuilding will require planning permission.

*The term “original house” means the house as it was first built or as it stood on 1 July 1948 (if it was built before that date). Although you may not have built an extension to the house, a previous owner may have done so.

*Designated land includes national parks and the Broads, Areas of Outstanding Natural Beauty, conservation areas and World Heritage Sites

Please note: The permitted development allowances described here apply to houses and not to:

Permitted Development for householders – Technical Guidance

You are strongly advised to read a technical guidance document produced by the Government. This will help understand how permitted development rules might apply to your circumstances.

View ‘Permitted development for householders – Technical guidance’ on Gov.uk

Building Regulations UK

Do I need building regulations approval for a garden room?

The most important factors are:

  • Building Regulations do not usually apply unless you want to sleep in it

  • Under 15m2 internal floor area can be installed close to any rear boundary

  • Over 15m2 and up to 30m2 needs to be a minimum 1m from any boundary*

If you want to put up small detached buildings such as a garden shed, garden room or summerhouse in your garden, Building Regulations (except Part P for Electrical works) will not normally apply if the floor area of the building is less than 15 square metres INTERNAL and contains NO sleeping accommodation.

If the internal floor area of the building is between 15 square metres and 30 square metres, you will not normally be required to apply for building regulations approval, providing that the building contains NO sleeping accommodation, and is either at least one metre from any boundary, or it is constructed substantially of non-combustible materials. (*As a solution to this it is possible to coat the cedar cladding of your garden room with a non-combustible Intumescent paint for timber and wood, derivatives are available in Water and Solvent based forms with fire ratings of 30, 60 minutes.)

In many cases, these structures will be exempt from requiring approval under the Building Regulations if they meet certain exemption criteria.

Complying with Building Regulations.

Part A of the Regulations for structural integrity is fully complied with, ensuring that the building is constructed so that combined dead loads (weight of structural elements), imposed loads (snow, maintenance activities, etc) and wind loads are accounted for.  Issues addressed cover elements such as the size and bearing of roof timbers relative to the unsupported roof span per guidance issued by NHBC and TRADA.

Part L (does not apply to buildings under 50m2 internal floor area per Regulation 21) takes account of the insulation qualities of walls, roof, floor, doors and windows, and new Building Regulations introduced in April 2014 impose stricter fabric U-Values for England and Wales of: 

Part P In the case of Garden Buildings Part P applies and any work is notifiable to the Local Authority.  Work can be self-certified by an Electrical Installer who is registered as a competent person using aBS7671 electrical installation certificate for every job they undertake, with a copy given to the householder. This is supplied by One More Room LTD where we are contracted to do this work.

Please note: The information provided on this page is intended as general guidance only and should not be considered legally binding. Planning permission requirements for garden rooms can vary depending on individual circumstances and are always determined by local authorities. We strongly advise checking with your local council before starting any project to ensure you have the correct approvals in place.