In England most garden saunas and hot tubs don't need a planning application. A sauna counts as an outbuilding, and a garden outbuilding is "permitted development" if it meets a short list of conditions: single storey, not in front of the house, no more than 2.5m high within 2m of a boundary, and, with other buildings, covering no more than half the garden. Listed buildings, flats and protected areas such as conservation areas have tighter rules.
This guide explains those rules in plain English, how they apply to the saunas, hot tubs and cold plunges we sell, when building regulations come in, and what differs in Wales and Scotland. It is general guidance, not legal advice: if your house has any restrictions, ask your council before you order.
The permitted development rules in England
These are the main conditions for an outbuilding, including a sauna cabin, set out by the government's Planning Portal:
- Not in front of the house. No outbuilding on land forward of the wall forming the principal elevation, usually the front of the house.
- Single storey. Maximum eaves height 2.5m. Maximum overall height 4m with a dual-pitched roof, or 3m for any other roof.
- Near a boundary. Within 2m of a boundary, the building can be no more than 2.5m high.
- No more than half the garden. Outbuildings and extensions together must not cover more than 50% of the land around the original house (as first built, or as it stood on 1 July 1948).
- No raised platforms over 0.3m, and no verandas or balconies.
- Used for something incidental to the house. A sauna, gym or garden room is fine; it can't be a separate home or have sleeping accommodation.
Tighter rules apply if the house is listed (any outbuilding within its curtilage needs permission), is a flat or maisonette, or is on designated land: conservation areas, National Parks, the Broads, Areas of Outstanding Natural Beauty and World Heritage Sites. On designated land, outbuildings at the side of the house need permission, and buildings more than 20m from the house are limited to 10m² in total in National Parks, the Broads, AONBs and World Heritage Sites. An Article 4 Direction or a planning condition on your house can also remove permitted development rights.
How our saunas measure up
The height near a boundary is the rule that catches people out. Here are the overall heights of the saunas we sell.
| Sauna | Overall height | Within 2m of a boundary? |
|---|---|---|
| Fjell barrel | 2.06m (0.9), 2.25m (1.3 and 1.6) | Yes, under 2.5m |
| Lys cube barrel | 2.08m | Yes |
| Skog oval barrel | 2.25m | Yes |
| Kota cabin | 2.24m (2.6), 2.36m (4.1) | Yes |
| Lumi | 2.37m | Yes |
| Vik | 2.39m | Yes |
| Stille | 2.40m (1.5), up to 2.50m (5.3 and 8.2) | Yes, at the limit |
| Hytte and Stuga | 2.49m | Yes, just |
| Tind | 2.54m | No: keep it more than 2m from every boundary |
| Bastu | 2.61m | No: keep it more than 2m from every boundary |
Watch the base and the chimney. Heights are measured from the ground, so a base that raises the sauna adds to its height. A wood-burning heater's chimney sticks up above the roof. If you are close to the 2.5m limit near a fence, either keep the base low or move the sauna more than 2m from the boundary.
Hot tubs and cold plunges
Permitted development covers "pools" as well as buildings, and a freestanding hot tub or plunge tub is low, so in most gardens it doesn't need permission. The same limits apply: not in front of the house, within the 50% rule, and the extra restrictions on listed buildings and designated land. Two things to watch:
- Decking. A raised deck or platform more than 0.3m high needs planning permission.
- The chimney. Our wood-fired Kilde and Varme tubs have a 2.7m chimney. Keep it well clear of buildings, fences and overhanging branches, think about where the smoke drifts, and burn dry wood. If you want the tub near a boundary, check with your council first.
Building regulations
Planning and building regulations are separate. For a detached outbuilding in England, the Planning Portal says building regulations will not normally apply if:
- the floor area is under 15m² and there is no sleeping accommodation, or
- the floor area is 15 to 30m², there is no sleeping accommodation, and the building is at least 1m from any boundary or built mainly of non-combustible materials.
Most garden saunas are well under 15m². Our largest, the Vik and Bastu, are 12.8m² and 11.5m² inside, but their outside footprint is larger, so if yours is close to 15m² ask your building control team how they measure it.
Electrics are covered by building regulations whatever the size. In England, a new circuit is notifiable under Part P, and a room containing a sauna heater is a "special location". Use a registered electrician who can certify the work.
Wales and Scotland
Wales has similar rules: 50% of the garden, nothing forward of the front of the house, and 2.5m maximum within 2m of a boundary. There are some differences. The Welsh Government's guidance sets a 2.5m maximum height for flat-roofed outbuildings and 3m for single-pitch roofs, with a lower limit for buildings very close to the house. Check gov.wales before you order.
Scotland measures the boundary rule differently: any part within 1m of a boundary must be no higher than 2.5m, the overall height limit is 4m and the eaves 3m, and the building must be behind the house. In a conservation area the footprint is limited to 8m², and in the grounds of a listed building to 4m² (with listed building consent). Scotland also has its own building standards, so ask your council's building standards team about a building warrant.
Before you order: a quick checklist
- Is the house listed, a flat, or in a conservation area, National Park or AONB? If so, ask the council first.
- Will the sauna sit within 2m of a boundary? Check its height, plus the base and any chimney, stays at or under 2.5m.
- Is it behind the front of the house, and do your outbuildings cover less than half the garden?
- Will you need a raised deck? Keep platforms under 0.3m or apply for permission.
- Have you booked a registered electrician for any electric heater, chiller or SPA tub?
If you are unsure, councils offer pre-application advice, and you can apply for a Lawful Development Certificate to confirm a project is permitted development. For everything else about choosing a sauna, see our garden sauna buying guide.
Common questions
Do I need planning permission for a garden sauna in England?
Usually not. A garden sauna is an outbuilding and is permitted development if it is single storey, not in front of the house, no more than 2.5m high within 2m of a boundary and, with other buildings, covers no more than half the garden. Listed buildings, flats and designated land have stricter rules.
How close to my fence can I put a sauna?
As close as you like under permitted development in England, provided it is no more than 2.5m high within 2m of the boundary. Leave enough room to build it and to treat the timber.
Do I need planning permission for a hot tub?
Usually not for a freestanding hot tub in a back garden in England. A raised deck over 0.3m, a listed building, or designated land such as a conservation area can change that.
Does a garden sauna need building regulations approval?
Normally not if it is detached, under 15m² and has no sleeping accommodation. The electrics still need to comply: a new circuit is notifiable work under Part P, so use a registered electrician.
Can I use a garden sauna building as a bedroom?
Not under permitted development, which covers buildings used for purposes incidental to the house. Sleeping accommodation also brings an outbuilding under building regulations, so ask your council first if you want a room to sleep in.
Find a sauna that fits your garden
Every sauna page lists the outside size. Send us a photo and rough measurements of your garden and we'll tell you which fit.
