The Sauna Co.Design yoursSheet 401 · Guide
Planning permission for a garden sauna in Gloucestershire
Most garden saunas in England go up without an application. Whether yours can depends on your plot, your address and what is already in the garden. This is what we check, and where the rules come from.
401.1 · The short answer
Usually no application. Sometimes one.
In England a garden sauna is an outbuilding. An outbuilding that stays inside a set of limits is permitted development: no application, no fee, no waiting. The limits are listed below and they are not complicated.
Three things take a plot outside them: a listed house, a designated area (which covers a large part of Gloucestershire), and a garden that is already well built on. Each is a question about your address, not about the sauna, which is why we ask for the address before we draw.
401.2 · The limits
What permitted development allows
These come from Class E of the General Permitted Development Order. Every one has to hold for the application to be unnecessary.
- Behind the house. Nothing forward of the principal elevation.
- Single storey. Eaves no higher than 2.5 metres. Overall height no more than 4 metres with a dual-pitched roof, or 3 metres with any other roof.
- Within 2 metres of a boundary, overall height no more than 2.5 metres.
- Together with every other outbuilding and extension, no more than half the garden around the original house is covered.
- No veranda, balcony or raised platform higher than 0.3 metres.
- Incidental to the enjoyment of the house. A sauna is.
Each of the four sauna forms we build has a footprint under 10 square metres, and the 2.5-metre line near a boundary is the one that decides most gardens. We draw the height against it on the site survey rather than from a brochure.
401.3 · The Cotswolds
Where the rules tighten
The Cotswolds National Landscape, which was the Area of Outstanding Natural Beauty until 2023, covers a large part of the county. Many towns and villages are conservation areas, including much of central Cheltenham. On this land two further limits apply.
- An outbuilding more than 20 metres from any wall of the house may not take the total area of such buildings above 10 square metres.
- In a conservation area, no outbuilding between a side wall of the house and the boundary.
A listed house has no permitted development for outbuildings at all, and nor does anything within its curtilage. There, an application is needed before any work, and the council will want to see the drawings.
401.4 · Building regulations
A separate system, and the heater is in it
Not needing planning permission says nothing about building regulations. A detached building with a floor area of no more than 15 square metres and no sleeping accommodation is exempt (Schedule 2, Class 6). Between 15 and 30 square metres it is exempt if it stands at least 1 metre from every boundary or is built substantially of non-combustible material. Each of our four sauna forms is under 15 square metres.
The electrics are not exempt. Regulation 9(3) keeps Part P for a building powered from the house, so an electric heater's new circuit is installed and certified under Part P. Part J, which covers stoves and flues, is not among the parts regulation 9 keeps, so in an exempt building a wood-fired stove is not controlled by Building Regulations. In a building that is not exempt, it is. Either way we have it fitted by a HETAS-registered installer, to the stove maker's instructions.
Cheltenham and Gloucester include smoke control areas. In one, a wood-burning stove must be an exempt appliance or burn only authorised fuel. Check the address on the council's smoke control map before choosing wood.
401.5 · In doubt
When to ask the council anyway
If the plot is close to a limit, or you expect to sell the house, a Lawful Development Certificate is worth having. The council confirms in writing that the build did not need permission. It costs less than a full application and it answers the question a buyer's solicitor will ask.
Where there is any doubt we suggest confirming with the local authority before anything is ordered. In Gloucestershire that is one of six councils, listed under Sources, and each publishes its own conservation area map.
Check an address against the council's own records: the planning checker on No.91 Developments' site
Before anything is ordered
Planning. Many garden saunas can be installed under permitted development, so a full application often isn't needed - but that depends on your plot: height, distance to a boundary, how much of your garden is already built on, and any conditions on your property. We never confirm planning status from a brochure. The Cotswolds is a National Landscape and many villages are conservation areas, where the rules are tighter, so we check your address's designation rather than assume it. Where there's any doubt we'll suggest confirming with your local authority before anything is ordered.
Sheet 00 · Yours
Describe your garden
A few plain words is enough. The studio turns them into a first design, and we confirm it on a site visit before anything is built.
- Drawn for one garden and built once, to your space and the way you will use it.
- Designed and built from our Gloucestershire workshop. Installed across England and Wales.
- One team from the first sketch to the last screw, electrics included.