Outbuilding Design

Outbuilding Design

Whether it’s a garden office, a home gym, a games room the possibilities are almost endless when it comes to what an outbuilding can offer you and your home. In terms of outbuilding design again the possibilities are almost endless, owing to their nature of being detached from the host property there is usually a lot of flexibility when it comes to their external look, as with extensions there are permitted development rights in place that will allow you to potentially design and construct an outbuilding without formal planning permission.

If you’re thinking about an outbuilding project or you’re unsure about how to go about your outbuilding design, take a read of the below to get you started on your journey.

Outbuilding Design and Permitted Development

What Makes Great Outbuilding Design?

Unfortunately, as with most aspects of the architectural industry, there is an equal number of examples of great outbuilding design and poor outbuilding design.

Part of the issue here is that whilst the adoption of permitted development rights allows for quick and easy outbuilding construction it also takes away the local authority’s opportunity to review the outbuilding design and ensure that the project is of a quality that is suitable to be approved.

At GBS Architectural we treat outbuilding design with as much care and thought as we do to an extensions design or even a new dwellings design. Understanding our clients' brief is the most important aspect of the outbuilding design process, we will ask questions such as what is the aim of the outbuilding now and for the next 5 years? What activities be conducted within the outbuilding? And how will the outbuilding link to not only the garden but also the main home?

It is vital that for great outbuilding design that a holistic view is taken on the project, whilst it may look like a ‘box at the bottom of the garden’ it absolutely isn’t, it is a detached extension of the home and therefore we need to look at the outbuilding design from an internal and external point of view. Ensuring that the outbuilding ‘connects’ to the home and to the garden is key to great outbuilding design.

Including some features, glazing can act as a real highlight to the outbuilding design, whether this is some large sliding doors or roof windows you can always ensure that all areas of the outbuilding are well lit with much-needed natural light.

Material choices are a fun part of outbuilding design, owing to their usually smaller nature there is a great deal of flexibility in how the outbuilding is construction whether this is a traditional construction such as brickwork or something lighter and ‘greener’ like timber cladding.


Can I have an outbuilding at my home?

This is always a tricky question to answer with full confidence without knowing the exact conditions of your property in terms of its local planning constraints, we can however offer a broad overview of what may be achievable for you and your potential outbuilding design.

Having access to permitted development rights can make building an outbuilding easier than ever and mentioned earlier, have a read of our permitted development blog post for more in. Provided that you fulfil the criteria set out within the guidance you go ahead and start the architectural process with full confidence that you will have no issues from the local planning authority.

If your outbuilding design falls outside of the parameters set out within the permitted development rights or if your property doesn’t have access to the rights, there are of course options available to you. Formal planning permission would be required in this instance and this is where proper outbuilding design is important to ensure that the local authority takes no issue with the proposal; provided that you engage an architectural practise specialising in outbuilding design such as ourselves you can maximise the potential of your outbuilding.

Outbuilding Design and Permitted Development

Outbuildings London

Below is a brief overview of the permitted development rights for outbuildings that may be of use if this is a route you are looking to consider an outbuilding of some kind, for more specific advice we would recommend you give us a call to discuss your project.

For Outbuildings

  • No outbuilding on land forward of a wall forming the principal elevation.
  • Outbuildings and garages to be single storey with maximum eaves height of 2.5m and maximum overall height of 4m with a dual pitched roof or 3m for any other roof.
  • Maximum height of 2.5m in the case of a building, enclosure, or container within 2m of a boundary of the curtilage of the dwellinghouse.
  • No verandas, balconies, or raised platforms (a raised platform must not exceed 0.3m in height).
  • No more than half the area of land around the “original house” would be covered by additions or other buildings.
  • Any new building must not itself be separate, self-contained living accommodation and must not have a microwave antenna.
  • 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 the 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.


It is clear to see how permitted development does allow for a broad spectrum of outbuilding design especially considering that there is no specific guidance on the amount of glazing or material choices, utilising these rights can be a fantastic way to achieve something quite different from your home. What is also evident is that the rights may also restrict your outbuilding design when considering the height of the design especially considering that you will most likely want an outbuilding close to the boundaries of your property.


Outbuilding Design and Planning Permission

A more standard planning application and therefore full planning permission may be the route if you are looking at an outbuilding design that doesn’t comply with the permitted development guidance. We would always encourage our clients to maximise the potential of their outbuilding design and allow that to dictate the method of approval rather than the opposite.

The possibilities are almost endless when it comes to outbuilding design and planning permission. That’s not to say you can design whatever you want, you will need to ensure that any proposal complies with your local authority’s planning and design guidance to ensure that your proposal will be approved.

It may be that certain designs would not be accepted due to local architecture or that certain material choices would not be viewed favourably by your local authority, therefore it is vitally important that this guidance is reviewed before the outbuilding design process begins.

Our experience suggests that by handling the outbuilding design process this way we can ensure that we maximise the potential of our project whilst also ensuring a smooth stress-free planning process, any delays at this stage can set the project timeline back a substantial amount.

Outbuilding Design