Safety first installing outdoor saunas
Installing an outdoor sauna can do wonders to your occupancy, but before you invest in such a facility it is important to check what regulations apply.
In your quest to offer ever-higher luxury facilities to your guests, you may wish to consider installing an outdoor sauna. You may have an adequate unused outdoor space that you could deploy for this purpose, for instance.
Such a facility would not need a great deal of regular maintenance unlike, say, a bar, yet it can be turned into a cash generating facility for your business. You probably wouldn’t charge guests to use it, but once you advertise the fact that you have such a facility you are likely to find a general rise in occupancy.
If you decide to invest in such a facility then it is likely immediately to give your business a boost by attracting those for whom health and fitness is important but who do not wish to over-exert themselves whilst away enjoying the trappings of a luxury break. The word sauna itself is of course a search term often used by those seeking a few nights away in a luxury guest house or B&B, and it is something that can draw guests in during the quieter winter months.
If you are to contemplate such a development, before investing in the task of preparing your land and buying and installing your sauna the first thing you need to do is establish whether you will be able to comply with all the associated regulations, and secondly whether you are sure you will be able to monitor and control its use so that none of your guests end up doing themselves damage through over use or through raising the temperature too high.
The dangers are real. In 2010 for instance the annual sauna world championships were dramatically cancelled in their 12th year when a Russian man died after spending six minutes enduring a temperature of 110C.
Vladimir Ladyzhenskiy was pronounced dead after being dragged from the sauna by judges, and another contestant was hospitalised with burns.
Matthew Noble is sales and marketing manager at sauna specialist Aqualine. He suggests regulation is not as great a hurdle as you may imagine with the usual restrictions applying as they do for wood burning stoves in smokeless zones for example. Most outdoor saunas can be done under permitted development, he says.
Health and safety is mainly an issue with the heater for installing an outdoor sauna, he says. “This can be fitted behind a false wall with automatic essence and water dosing systems, thus removing the possibility for bathers to scold themselves or overwater the heater elements, which can damage them,” he says.
Space consideration is very important, he says. “Quite often people will design a large sauna with lots of glassware and fail to take into account the cubic volume of air and heat loss. All too frequently people build their cabin first and then hope they can find a heater that will be able to cope with the size.
“This is an issue if there is only a single-phase domestic supply when the heater required actually needs a three-phase commercial supply,” he says.
He adds: “It is also very important to get the correct tongue and groove shape and suitable bench materials from a sauna specialist to ensure that the walls are not going to warp and that all the wood kiln dried and wont off gas chemicals or saps when heated to a sauna temperature.”
Rules that govern outbuildings also apply to sheds, greenhouses and garages as well as other ancillary garden buildings such as swimming pools, ponds, sauna cabins, kennels, enclosures such as tennis courts and many other kinds of structure created for leisure purposes at home or at a guest house.
Outbuildings such as a shed to house an outdoor sauna are considered to be permitted development and therefore not in need of planning permission. However, there are limits and conditions to this which could affect your proposed sauna.
- No outbuilding on land forward of a wall forming the principal elevation.
- Outbuildings and garages to be single storey with maximum eaves height of 2.5 metres and maximum overall height of four metres with a dual pitched roof or three metres for any other roof.
- Maximum height of 2.5 metres in the case of a building, enclosure or container within two metres of a boundary of the curtilage of the dwellinghouse.
- No verandas, balconies or raised platforms.
No more than half the area of land around the original house may be covered by additions or other buildings. This restriction refers to the house as it was first built or as it stood on 1 July 1948 if it was built before that date. Although you may not have built an extension to the house, a previous owner of the property may have done so.
- In national parks, the Broads, areas of autstanding natural beauty and World Heritage sites the maximum area to be covered by buildings, enclosures, containers and pools more than 20 metres from house must be limited to 10 square metres.
- In the case of listed buildings, any outbuilding will require planning permission.
The permitted development allowances described here, with regard to proposed sauna development, apply to such structures being installed outside houses, and not to flats, maisonettes, converted houses, or houses created through the permitted development rights to change use. It does not apply either to areas where there may be a planning condition or other restriction that limits permitted development rights. If you are in any doubt it is advisable for you to check this out before embarking on any such project.
It is also recommended that you read government technical guidance documents for installing an outdoor sauna to help understand how permitted development rules might apply to your circumstances.
Unlike a plain garden shed, with saunas foundations are generally required to be able to transmit the load of the building safely to the ground. The extent to which foundations – normally concrete are required which will vary depending on the size and weight of the proposed sauna facility.
It makes perfect sense to ensure foundations are lain as a matter of course for your own peace of mind installing an outdoor sauna since you do not want the building structure housing your sauna to subside in any way, giving rise to cracks in the wall for example that may lose heat and therefore raise the cost of the fuel used to heat the sauna.
The foundations you choose may be cast as deep-fill, filling most of the trench, or shallow-fill, where the minimum thickness to transfer the load to the soil is provided.
There are other types of foundations for installing an outdoor sauna that may be used if the ground conditions do not make trench fill practicable. It is advisable to contact a structural engineer or speak to building control for further advice.
The type of soil that the foundation will sit on is important for two reasons: It should be able to bear the weight (load) of the foundation and the extension – different soils have different load bearing capabilities, and the way it reacts to variations in moisture content (such as in prolonged rainy or dry seasons) can lead to the soil expanding or contracting.
This is a particular issue with some clay soils installing an outdoor sauna. These changes mainly occur up to a certain depth, typically about 0.75m, so the foundations should be made deeper to avoid being affected by ground movement.
It is important to ensure that the excavation for the new foundation does not undermine adjacent structures. In general it is recommended you excavate at least to the same depth as the bottom of the foundation to the adjacent building. If the excavation runs alongside an existing footing then care will be needed – for example, by excavating and concreting the foundation in shorter sections to avoid undermining a whole length of an adjacent structure.
Trees will draw moisture from the ground around them and beyond through their root system. As moisture is drawn from the ground it will have a tendency to shrink. The extent to which the ground will shrink will depend on the type of soil. Clay soils shrink more than other types of soil, for example, so excessive movement of the ground could cause damage to the foundation and the structure it supports.
The vulnerability of the ground to root damage is also determined by the size and type of tree. The size to which a tree or shrub will grow when it reached its mature height, and the tree type itself, will determine how much moisture it generally draws from the ground. Eucalypytus or gum trees for example have an insatiable thirst.
The presence of trees in clay soil areas can mean foundations need to be significantly deeper than might be first expected, although if the trees are far enough away, there may be no impact.
There are other regulations that may apply when you erect your sauna such as those relating to drains and sewers. As the weight from the foundation of your sauna is transferred to the soil it will spread downwards outside the footprint of the foundation at a typical angle of 45 degrees. If a drain or sewer is within the area covered by that area then there is a risk that it could be affected by the load from the foundation and possibly crack. In such cases the foundation excavation should normally be at least to the same depth as the bottom of the deepest part of the drain, sewer or its trench.
You may consider the measures to be excessive, but for the sake of your own peace of mind you really ought to heed whichever regulations apply to your situation and property.
Sensible sauna use
- It is important to ensure none of your guests stay in the sauna for too long. A period of 15 to 20 minutes at a time is generally considered the sensible maximum, although up to 30 minutes should be acceptable. The length of time the body can tolerate will vary from person to person. You should advise guests that if they are sensitive to heat, they should start off with a short stay.
- Guests using the sauna should be advised to rest for at least ten minutes afterwards to let their body recuperate.
- They must rehydrate. Encourage those who use the sauna to drink plenty of water both before they enter and afterward. They may also want to eat something salty afterwards.
- Encourage people to go in pairs or groups. This means that if problems do occur, someone else is on hand immediately to assist. You can stress that sauna is a social affair.
- Suggest guests cool down after their sauna. There is a Finnish tradition of going straight from the sauna into the snow. A less extreme way for guests to cool down is to take a cold shower. This has the added bonus of removing any impurities that the body has expelled and prevents their reabsorption.
- The heat of a sauna makes the heart work harder. Advise your guests to avoid using the sauna if they have heart problems.
- Never allow guests to drink alcohol in the sauna and advise them not to go in straight after a large meal or after strenuous exercise.
- Saunas can burn and too much time in the sauna at a too high temperature can lead to blistering. Your guests shod be advised that if their skin starts to sting, they should get out. The average sauna temperature is about 85C though it can range anywhere between 60C and 110C. It was at the upper end of this range that the Russian participant perished in the sauna world championships, so seek advice from the supplier on means to restrict the heat levels.
- Guests using your sauna facility should be warned ahead of time that If they start to feel dizzy, nauseous or have a headache, they should leave immediately. There is no point in taxing the body to extremes – especially not in the name of wellness.
- Moderation is key.