A garden room brings a touch of luxury to any home. They harbour endless potential as additional sleeping, living, and work spaces without the time consumption and expense of a conventional extension.

Understandably, a huge aspect of their appeal is their excellent convenience, so it will be a comfort to know that most garden rooms do not require planning permission. Nevertheless, it's best to be fully informed before making your garden room dream a reality.

There are some exemptions where outbuildings of specific size, place, and function may need planning permission approval. Here is everything you need to know about the rules of outdoor construction so you can soon delight in your luxury annex retreat.

What Are The Rules For Building A Garden Room?

The rules of building a garden room can be classified into three concerns; these being the building’s total size, what you plan to use it for, and the place in which you live. Most UK homes come with certain permitted development liberties.

However, if you live in a classified area, such as an AONB (Area of Outstanding Natural Beauty), conservation, or heritage site, there will be distinct regulations covering what alterations you can make to your property. Listed buildings have further restrictions on the types of developments their residents can approve. The first step to confirming your planning rights is to check with local authorities, such as a council planning officer.

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.

View ‘Is building regulations approval needed for an outbuilding?’ on Gov.uk

The Size and Place of Your Garden Room

In the UK, 3 metres is how high a garden room can be without planning permission. This includes the height of the roof and is conditional to the garden room being single-story and not having a balcony, veranda, or raised platform.

The placing of your garden room is also something that may be subject to local approval. In order to avoid official checks, it must not be attached to your home in the style of a conservatory or extension. It also must be stationed in your back garden, as opposed to at the front or alongside your home. If your garden room covers more than 50% of the land enclosing your house, this may also trigger the need for planning permission approval.

Interestingly, the rules around these two factors can influence each other. For example, the maximum height of a garden room without planning permission may be limited to 2.5 metres if it is situated less than 2 metres from the edge of the property’s boundaries.

The Function of Your Garden Room

Garden rooms are incredibly versatile and can be made to suit a multitude of purposes, popular choices include a home office, extra relaxation space, a playroom, sleeping accommodation, and even a cinema room. The key to surpassing planning permission obligations is to ensure that your garden room’s usage is ‘incidental’ to the primary dwelling. This means that the function of your garden room is merely complementary to your home, providing additional living or workspace, rather than being self-contained accommodation.

To break this down, a home office is typically a safe option. Using it as a personal work or study space means it cannot be interpreted as an independent living quarter. The only potential issue is if you plan to use your garden room office as an occupational base where you hold in-person meetings with colleagues and clients. The additional traffic and footfall this could bring may impact the neighbourhood, and thus require the consent of nearby residents.

Incorporating features such as a kitchen unit or bathroom might necessitate planning permission. It will likely require intense plumbing and electrical work that will need to be overlooked by professionals. Installing electric power in your garden room means following part P of Building Regulations, whereby a qualified electrician must be the one to connect the separate consumer unit to the mains supply.

One of the most common queries concerning outdoor buildings is whether or not you need planning permission to sleep in a garden room. The benefit of a guest bedroom is a major source of appeal for many people looking to build their own garden room.

This, however, is the trickiest option when it comes to avoiding planning permission. Of course, sofa beds and any other furniture suitable for temporary sleeping accommodation if perfectly permissible without the need for consent from local authorities. Whilst having a bedroom in your garden is very much achievable, set-ups that are clearly designed to be more permanent will have to be officially certified. These styles of ‘granny annexes’ that come fully equipped to live in are enormously valuable. The comfort of having all the amenities in this one luxurious space not only inflates the value of your home, but allows you to keep loved ones close whilst still maintaining their independence, or gift yourself an isolated, self-contained retreat.

The pleasure of a fully furnished holiday home in your own back garden may indeed be well worth the process of acquiring planning permission, where it’s confirmed to have met UK Building Regulations.

Building a Garden Room Without Planning Permission

To recap on the steps you can take to avoid the need for planning permission, the maximum height and specific use and placing of your garden room must be:

  • 2.5m within 2m of the property’s borders
  • 3m if further than 2m of the property’s borders
  • If the garden room has a pitched roof, it can be 4m high if further than 2m of the property’s borders
  • the function of must be ‘incidental’ to the main property

Garden Rooms by The-Oi

The expertly trained members of the team at The-Oi are here to answer any questions you may have about the complexities around planning permission and your dream garden room. As leaders within the home improvement industry, The-Oi can offer the most up to date information about the design, planning, and construction process of creating sophisticated outdoor living and shading spaces.

We work with only the best products and materials sourced from the UK that are suitable for any style or purpose you wish your garden room to fulfil. The final product will offer you a premium additional living space that lives up to your ideal hopes of the perfect home office, gym, cinema, or anything else.

You are invited to take part in every step of the design process, meaning all your unique requirements big and small are part of our promise.

Contact The-Oi today.