Sauna installation guidelines

Preparing for installation

  • Read the user manuals for the sauna materials and the installation guides for all electrical devices to be used
  • Check that there is adequate ventilation in the room where the sauna is to be installed
  • Make sure that the wooden materials won’t come into constant contact with water, for instance at the bottom of the wall, during installation
  • Ensure that the external surfaces of the sauna won’t remain exposed to water or moisture upon installation
  • Ensure that any electrical work, including installation of the electric sauna heater, is done by a licensed electrician


Treating wooden components

  • It is obligatory to treat the wooden parts with special liquids to protect the wood from moisture. Treatment liquids are available in well-equipped construction stores. The manufacturer is not responsible for the products which are damaged due to the lack of protective treatment or incorrect installation.
  • Dust all of the wooden sauna components and then clean them with a sauna detergent before allowing them to dry
  • Treat the walls and ceilings on both sides with a specialist sauna finish product such as Tikkurila Supi Saunasuoja and then treat all surfaces of the seating materials with a sauna bench protection product like Tikkurila Supi Laudesuoja
  • Don’t use paints or varnishes, as the wood must be able to breathe


Installing the heater and heating stones

  • Ensure that the heater is installed according to the manufacturer’s instructions
  • Install the heating stones as directed by the manufacturer and make certain that the heating elements aren’t visible, as pouring water directly onto them can reduce their lifespan
  • Wash the heating stones to remove any production chemicals
  • Important – do not use your sauna when heating it for the first time!
  • During the first heating, do so under supervision to a temperature of about 100°C for two hours, keeping the sauna well ventilated both during and after heating; the heat will cause the wood to absorb the treatment products, which will form a protective layer

Advice for sauna maintenance

During use

  • Only throw water on the heater, not on the walls or benches
  • Don’t wear wet swimsuits in the sauna, as water from these will damage the bench
  • To keep the bench fresh, we recommend using seat covers – these can also make it more comfortable to sit on the bench when it is hot
  • Keep an eye on the heating stones, as they may crack over time – whenever necessary, they can be replaced or
    more stones can be added


After each use

  • Wipe the benches with a clean, damp cloth – don’t use running water to clean them, and ensure that excess water doesn’t pool on the wooden surfaces
  • Use appropriate cleaning products for the benches and other wooden components, reading the instructions first
  • After cleaning your sauna, allow the surfaces to dry and ensure that the room is well ventilated – we recommend leaving the heater on for at least half an hour with the air vent open and the door and windows closed
  • If possible, lift up the benches to allow them to dry better


At least once per year

  • Treat the sauna’s wooden surfaces with an appropriate product (see Treating wooden components above) – this should be done more frequently if the sauna receives intensive use
  • Clean all surfaces of the seating materials, walls, and ceilings using a soft brush or cloth and a specialist cleaning product, following the instructions on the packaging
  • For deeper stains and soiling, gently clean the bench using a fine sandpaper before treating the sanded surface with a wood preservative (see Treating wooden components)
  • Avoid using cleaning agents that are unsuitable for saunas – for example, disinfectants bleach the wood and can spoil its surface
  • Inspect the fastenings on the benches and supports, tightening any screws if necessary; they may loosen over time due to changes in the wood caused by heat and humidity


Things to avoid

  • Don’t dry textiles in your sauna, as this can be a fire hazard – excessive moisture can also damage the surface of the wood
  • Avoid heating the sauna beyond the maximum temperature specified by the heater manufacturer – excessive heat may create a fire risk or cause the wood to warp
  • Never use a pressure washer or running water when cleaning your sauna, as excessive moisture can permanently damage the structure and surface of the wood


How wood changes when used in the sauna

  • Wood is a natural material, and its surface may crack or bend when used in the sauna
  • This is normal due to the extreme and rapid changes in temperature and humidity that occur
  • The risk of wood deformation depends on the material and intensity of use – the effects are also more visible in wider boards
  • Wooden materials in the part of the sauna most exposed to the hot steam may darken over time
  • When new, thermally modified wood may give off a noticeable scent as the sauna is heated, but this will diminish over time

Suggestions for using intensely thermally modified wood

Thermory’s range of wooden sauna products includes a large selection of thermally modified products. Of these, the most exclusive and luxurious items are made with wood that has undergone intense thermal modification, which gives it a beautiful rich brown color, such as dark alder and radiata pine. These elegant materials can be sensitive, and they require special care and attention to maintain their appealing properties.

  • Handle packs of wood or individual boards with care during installation
  • Don’t scratch the surface of the wood or slide the boards over one another
  • Thermally modified wood has a distinctive scent that diminishes over time but never fully vanishes – however, it will lose this scent more quickly if the sauna is heated for an extended period while being ventilated
  • Treating the wood with a suitable wood oil or care product will also soften the scent
  • Avoid washing untreated thermally modified wood with water, as this will intensify the scent
  • Please note that we cannot accept claims about the quality or scent of the wood after it has been cut, installed, or treated
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