The good news is that if the garden room falls within permitted development guidelines then garden rooms do not require planning permission.
There are a few criteria to take into account, primarily your property must be a house, as flats or maisonettes, for example, do not qualify. If you own an older property, it can also be helpful to check to see whether a change of use has been granted in the past. As permitted development rights may not apply in some circumstances where a change of use has previously been granted. If any part of your property is classed as listed, then full planning permission will be necessary. Garden Rooms generally fall under Class E of permitted developments and as such can not take up more than 50% of your garden area, this includes other out-buildings which currently count towards this figure.
No, in order to fall under the class E permitted development rules, it cannot be classed as self-contained living accommodation. This means that there can be no sleeping accommodation in the garden room. Planning permission would need to be applied for.
To classify as a garden room under permitted development rules, it must be single-storey with a maximum eaves height of 2.5m. Although this is the maximum eaves height, the shape of the roof and the location of the outbuilding are also important factors. In normal circumstances, a dual pitched roof can have a maximum height of 4 metres while any other type of roof is limited to 3 metres. The exception to this is when the building is within two metres of the boundary of your property when the overall height is restricted to 2.5 metres. Additionally, no TV or Satellite type aerial can be fixed to the Garden Room without planning permission.
If you or any previous owners of the property have extended the property since 1948, it may be that previous extensions have used up some or all of your permitted development allowance. This is because you are not permitted to build on more than half the area of your overall property without applying for full planning permission.
To qualify as part of your permitted development allowance, the garden room must be located behind the main front wall of the original house. Ie. As it was when it was first built or on 1st July 1948 if an older property.
If your property is in a National Park or a conservation area, then you will not be able to build to the side of your property without planning permission.
Any garden room built more than 20 metres from your property will also need to be less than 10 square metres to fall into the permitted development guidelines.
If the garden room has raised decking this can be no higher than 300mm. Planning permission is generally required for verandas or balconies.
There can be no antenna without planning permission.
If your property is in an area with an Article 4 direction or other restriction (listed status), then planning permission may apply.
Building Regulations can be complicated but primarily they are defined by use, size of building and location. Typically, most of our customers do not need to meet them but each customer should consider their own individual circumstances and ensure that they do not use the building in a way that requires building regulations.
If you want to put up small detached buildings such as a garden room 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 internally and contains no sleeping accommodation.
1. Building Regulations do not usually apply unless you intend to sleep in the Garden Room.
2. Only Garden Rooms with an internal floor area under 15 square metres can be installed close to any rear boundary.
(we require a minimum working space of 450mm around all 4 sides of the building.)
3. Over 15 square metres and up to 30 square metres needs to be a minimum of 1 metre from any boundary.
This guidance applies to planning regulations in England only. Policy for Scotland and Wales may differ slightly please check with your Local Authority.
If you have any doubts about any of the points raised please check with your local planning authority.
Which's guide to garden rooms and planning permission.