Back in 2021, myself and another member of the sauna community created a group to bring mobile sauna pioneers from across the UK together into one place, to share useful information and spread the amazing personal and communal benefits of sauna.
Last year, The British Sauna Society elected myself as the Technical Officer. My aim has initially been to focus on and monitor safety concerns regarding sauna design and construction.
The BSS are working towards a sauna certification scheme which would detail the requirements for an enjoyable and healthy sauna experience but would initially be focusing on safety as its primary concern.
The guidelines have not yet been published but I think it’s important to present the current draft in order for members of the community to better understand our goals.
Many European countries have strict regulations regarding sauna design and construction but unfortunately, possibly due to a previous lack of popularity, the UK has no regulations concerning sauna construction other than the ones listed in the IET wiring regulations; special locations.
BSS guidelines include but are not limited to;
Materials
- All materials should be rated for temperatures in excess of 100C. This means that any timber must be untreated softwood, as softwood conducts less heat than hardwood and would be less hot to the touch. Treated timbers would off-gas harmful chemicals under high temperatures and present potentially toxic and/or carcinogenic compounds into the air, possibly causing nausea and respiratory issues.
- Plastics should not be used within the sauna space unless manufacturers specifications can show the stability of the product under sauna-like temperatures, for example; plastic bubble wrap foils, plastic coated vapour/radiant barriers, vinyl flooring, rubber seals etc.
- Insulation, if installed, must also be sufficiently temperature rated – Rock Wool and Sheep Wool, provided that no bonding agents have been used, are inert materials that can withstand temperatures much higher than those associated with sauna. Kingspan produce a sauna specific insulation called Sauna Satu and Finnfoam PIR would also be suitable – both examples are rated to over 110C.
Unsuitable examples of sauna Insulation would be; Standard solid insulation boards such as Kingspan or Celotex as such Insulations, once heated above 60C, would begin to break down and produce Hydrogen Cyanide gas.
Pink or yellow fibreglass insulation is also an unsuitable material because of the bonding agents used during manufacture, which traditionally include Formaldehyde and other volatile compounds. Polyester and Polystyrene are also examples of unsuitable materials.
Ventilation and Drainage
- Contrary to popular belief, sufficient ventilation is also an important component of sauna design and construction. Ventilation not only aids in heating the sauna space more efficiently but it also provides the bathers with a fresh supply of oxygen, exchanges the stale air and prevents the sauna space from developing mould and fungal growth; which could cause respiratory issues especially amongst more sensitive bathers.
- Drainage would provide a similar benefit in terms of avoiding mould and would help to prevent any accidents associated with slips and falls.
Heater/Stove
- Generally, commercial and domestic saunas are warmed with electrical heaters though wood burning stoves are becoming increasingly popular, especially in outdoor sauna cabins and mobile saunas.
- Stoves must be designed and approved for sauna use and must carry the CE approval – EN15821 or equivalent.
- Cast-iron stoves would be unsuitable due to their tendency to contract and crack when making contact with water after being thrown on the rocks. This could result in a potential fire hazard, exhaust gases filling the sauna space and risk of Carbon Monixide poisoning.
- Heater/Stove safety clearances must be met in accordance with the manufacturers guidelines.
After extensive research and conversations with sauna builders internationally, we believe these are the core considerations to take note of when constructing a sauna.
The British Sauna Society will be pushing for sauna regulations to be followed in the UK. This ideally will involve guidance becoming regulations, to ensure safe standards are upheld.
This is not intended to make sauna building harder or less accessible! If anything, it’s meant to make things easier, to ensure safe sauna construction and to make sure sweat bathing culture in the UK can flourish and benefit the health of bathers.
