One of the most common questions we get asked is: “Do I need planning permission to have a garden room built?”

Generally speaking, garden rooms and summer houses are great alternatives to house extensions as planning permission isn’t required, however, there are exceptions to this rule.

Most garden buildings such as garden sheds, garden rooms and summerhouses do not require prior planning permission as long as specific conditions are met. Buildings such as these are covered by  ‘permitted development rights’.

Below is an overview of your permitted development rights and the exclusions. Please contact your local planning office or us for further planning permission advice – we’re here to help!

Permitted Development Rights Guidelines

Height: Garden rooms and summer houses must be single-story buildings. Buildings within 2 metres of a property boundary must not exceed 2.5 metres in height. Buildings that aren’t within 2 metres of a property boundary must have a maximum eaves height of 2.5 metres and a maximum overall height of 4 metres if the building has a dual pitched roof. This decreases to 3 metres if the building has a mono-pitched roof.

Area: Garden rooms must cover less than 50% of the original land/garden area around your home. Extensions and other outbuildings added to the original house must be included when calculating this 50% limit.

Location: Outbuildings must be built to the rear of a property – garden rooms are not covered under permitted development rights if they are built in front of the principal elevation of your house (generally understood to be the front of your house).

Usage: Garden rooms can be used for many day-to-day activities; however they are not allowed to be used for overnight stays or as self-contained accommodation units. Commercial use is also not allowed. These uses would require prior planning permission.

Extras: No terraces, verandas or balconies can be added to an outbuilding under permitted development guidelines. Any raised decking that links to a garden room must be less than 3cm high to ensure your neighbours’ privacy is respected.


The permitted development guidelines above cover UK houses only – flats, apartments, maisonettes and converted houses do not have permitted development rights. Different regulations apply to these properties.

Exclusions do also apply to some UK houses. Certain UK properties fall within ‘designated areas’ where permitted development rights are far more restricted.

Examples include houses within:

  • Conservation Areas
  • National Parks
  • Areas of Outstanding Natural Beauty
  • World Heritage Sites
  • The Broads

In these locations, the total area of any outbuildings must not exceed 10 square metres and the buildings must sit more than 20 metres away from any exterior wall of your house.

Larger buildings can be constructed if planning permission is granted.

If you live in a listed building, you will require full planning permission for any structural changes to your home or additions to your garden.

Again, if you’re unsure whether you need prior planning permission, it’s always best to double check before any building commences. Contact a member of our team who will be happy to help or check with your local planning authority.

If you do need to obtain planning permission to build a garden room, don’t let this put you off. Attaining planning permission is often less complicated than it first seems. The latest government figures show that 87% of all planning applications are successful. Also, the results are worth the extra time and money spent from gaining planning permission.

At GlasHaus we’re passionate about the lifestyle benefits that garden rooms provide, so we know the rules inside out. We’re always on hand to create a garden room that’s fully compliant with permitted development rights or to offer advice when it comes to attaining planning permission. Just get in touch – we’d love to help!