Do garden rooms need planning permission?
The “permitted development rights” legislation in the UK describes what most homeowners in most parts of the country may develop without having to apply for planning permission. Category E, Outbuildings, covers garden rooms.
Whether or not you need planning permission depends on this legislation: in a nutshell, if your property qualifies for permitted development rights, you are allowed to build a garden room provided that it complies with the restrictions described in the legislation for Category E, Outbuildings.
If your property does not qualify for permitted development rights, this is usually down to one of two reasons:
The property is a listed building, or is situated in a conservation area
The permitted development rights have been removed by your planning department as part of a previous planning application (also known as a Clause 4 Exclusion).
If your property does qualify for permitted development rights, but you want to build something that does not comply with the restrictions described in the legislation (usually due to size / dimension, or position on the curtilage of the property, or the intended use), then you need planning permission.
What are the restrictions around height and width of a garden room?
Standard regulations when building less than 2m from a boundary state a maximum height of 2.5m. There is no mention of a restriction on the permitted width in the regulations. We regularly build across the complete width of Victorian terrace gardens (typically between 4m and 6m wide).
The maximum size is determined by the restriction that you are not allowed to consume more than 50 percent of the garden for any building projects as measured in the original curtilage. This means that extensions and so on count towards that consumption of space.
Be careful about the total size, however. The maximum permitted footprint could be quite large, based on the curtilage, but it’s safe to say that anything over 30m2 should probably be checked. You can apply for a Certificate of Lawful Development, which is a rubber-stamping of your designs and equivalent to permission from the planning authority.
Do you have to consult neighbours before building a garden room?
No, but it’s sensible to let them know you’re planning to do this, and do what you can to keep them on side.
Can you rent your garden room out?
Not legally unless planning permission has been agreed.
Can you use it as a bedroom?
People do! Occasional use is unlikely to raise eyebrows. If you’re planning on doing this structurally, you should seek permission.
What else do I need to know about planning permission and garden rooms?
Planning departments have a scary reputation in some towns. We all know stories, hopefully told to us rather than experienced by us, of planners refusing to grant permission to applications that sound reasonable and straightforward. So far, we have not had an application refused.
We don’t know for sure, but we like to think that’s because our designs are attractive and sympathetic to the surroundings, and because our project descriptions use wording that helps to sell the intent.
Garden rooms used as annexes for a retired parent, for example, help families to stay together affordably and take the load for care off the state. You can pitch that persuasively and appealingly, or miss a trick and not even mention it.
And remember, garden rooms are here to stay, post-pandemic. Hybrid working both from home and in the office is much more likely to be the norm for most businesses that can afford that, and nobody likes to set up office in the kitchen, or a child’s bedroom.
Ten years ago, garden rooms were few and far between. We remember explaining the concept to people for whom the idea of one or two rooms in a garden was alien. Nowadays, they’re everywhere! So planners understand them, too.
And if you’re going to be using your room for something that needs permission, or you need permission because of the above reasons, then specifying a robust structure that would pass building control is part of the journey to a successful application.