Planning permission checker

Start with how you plan to use the sauna. Planning Portal includes sauna cabins among outbuildings used for purposes incidental to enjoying a house. A private garden sauna can fit that category, but these rules do not cover separate self-contained living accommodation or a change of use.

The allowances described by Planning Portal apply to houses, not flats or maisonettes. Certain converted houses are excluded too, as are homes created through specified permitted development routes. A planning condition or Article 4 Direction may restrict your property’s rights.

For a hotel sauna, holiday accommodation or another business, the domestic guidance is not a reliable test. Scottish Saunas notes that commercial use may bring different requirements. Your local planning authority will need to consider the proposed use, not just the building.

Planning Portal’s outbuilding limits work together. Meeting the height limit alone does not mean the proposal qualifies.

The building must be single storey, with eaves no higher than 2.5 metres. A dual-pitched roof allows an overall height of up to 4 metres; for another roof form, the limit is 3 metres. Within 2 metres of a boundary, the whole building must be no higher than 2.5 metres.

It must not stand forward of the wall forming the house’s principal elevation. Verandas and balconies are not permitted under these allowances, and raised platforms must not exceed thirty centimetres.

Coverage matters too. Additions and other buildings must not cover more than half the land around the original house. Planning Portal’s mini-guide counts sheds and other outbuildings, but also decking, raised platforms and extensions. That means previous owners’ extensions matter when you work out how much land is already covered.

The original house means the house when first built, or as it stood on the first of July 1948 if older. Some supplier summaries count only outbuildings towards the coverage limit. This checker follows Planning Portal’s broader calculation.

GOV.WALES includes sauna cabins in its outbuilding guidance. Its conditions differ from England’s, so the English figures should not be carried across to a Welsh proposal.

Welsh guidance limits outbuildings to one storey, with eaves no higher than 2.5 metres. Roofs with more than one pitch have an overall height limit of 4 metres. A single pitch or other roof form is limited to 3 metres, while flat roofs have a 2.5-metre limit.

Any part within 2 metres of a boundary must not exceed 2.5 metres in height. Proximity to the house brings a further restriction: any part within 2 metres of it must not exceed 1.5 metres.

Outbuildings must not sit in front of the principal elevation’s building line. A side-elevation restriction also relates to proximity to a highway. Read the full Welsh siting conditions; if that highway rule affects your proposed position, get clarification from your authority. Total outbuilding coverage cannot exceed 50% of the curtilage.

In England, Planning Portal says any outbuilding within a listed building’s curtilage requires planning permission. Permission is also required for outbuildings at the side of a property on designated land. This includes conservation areas and National Parks, along with the Broads, Areas of Outstanding Natural Beauty and World Heritage Sites.

In National Parks, the Broads, Areas of Outstanding Natural Beauty and World Heritage Sites, buildings and other specified structures more than 20 metres from the house face a combined coverage limit of 10 square metres.

Wales has its own protected-area conditions. In National Parks, Areas of Outstanding Natural Beauty and conservation areas, outbuildings more than 20 metres from any house wall must not cover more than 10 square metres in total. Development between the house’s side elevation and side boundary is not permitted under these allowances. Outbuildings within a listed building’s curtilage require planning permission.

The supplied Scottish guidance says a personal-use garden sauna may not need planning permission. Height and placement matter, as does the property itself. It recommends checking with the local authority, particularly for listed buildings and conservation areas. There is no complete numerical checklist in that guidance, so England’s limits should not be used as a Scottish approval test.

Scottish Saunas suggests trailer-mounted saunas may be less likely to need permission. It also warns that keeping one in the same place for years may attract closer consideration. Mobility is not a definite exemption.

The supplied material does not establish the Northern Ireland requirements. For a proposal there, seek guidance from your local planning authority rather than relying on another nation’s checklist.

Have the sauna’s measurements and proposed position ready, alongside a clear description of how you will use it. Record the roof form and both the overall and eaves heights. The footprint matters for coverage, which also needs to account for existing buildings and additions. Measure the distance from boundaries and, where relevant, from the house.

Your local planning authority can confirm whether permitted development rights apply to your property, including any restrictions from planning conditions or an Article 4 Direction. If a restriction applies or a limit is exceeded, this checker is not permission to proceed.

Planning permission does not settle the building regulations question. Planning Portal notes that exemptions depend on the outbuilding’s size, use and location, so you will need to check those requirements too.