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What is the best wood for sauna benches? | Lauta.fi

juho.kallonen@lauta.fi (Juho Kallonen) — Sun, 01 Nov 2026 15:53:34 GMT

The benches are where you spend the best moments in the sauna, and they are in constant contact with bare skin. Good bench wood does not get too hot, does not release resin and withstands rapid changes in temperature and humidity. This article explains which wood species suit sauna benches, how to size and fix the benches, and how to keep them beautiful for years.

What makes good bench wood?

Low thermal conductivity. Wood that conducts heat slowly feels cool even in hot steam.
No resin. Resinous wood releases hot, sticky resin as the sauna heats up.
Moisture resistance. The benches get wet and dry every time you use the sauna, so the wood has to cope with the changes without cracking.

Wood species for sauna benches

Aspen is a resin-free, light and almost knot-free hardwood. It conducts heat slowly and has a mild scent, which makes it many people's first choice for benches. For example aspen bench board 28x90 and aspen bench board 28x120.
Alder is resin-free with a warm reddish-brown tone. It also feels pleasant against the skin.
Thermally modified species, such as thermo aspen, thermo alder, thermo pine and thermally modified radiata pine, are dark and dimensionally stable. Thermal modification is carried out at high temperature using steam, and it removes the resin. For example thermo pine bench board 26x118 SHP.

Continuously heated sauna: thermally modified aspen is not suitable for a continuously heated sauna. Choose thermally modified alder instead – its tone is close to thermo aspen – or thermally modified radiata pine, which we offer in a wide range of products.

Thermally modified radiata pine: newly installed radiata pine can have a strong smell at first. Ventilate the sauna well, and the smell will fade.

Avoid untreated pine. Resin seeps out when the surface heats up. Thermally modified pine works well in the sauna because thermal modification removes the resin.

Width and direction define the look

Narrow boards create a traditional, rhythmic surface; wide boards a calm, modern one. You can use one or several widths and combine different species. A wide glued plank bench gives a minimalist look – for example aspen plank bench board 43x200 or alder plank bench board 43x200.

Decide whether the boards run lengthwise or crosswise, and take the heater's model and position into account.

Match the benches to the colour, width and profile of the wall panels. Benches are usually left in their natural colour, so the species largely defines the look of the sauna.

Size the benches correctly

Good steam comes from benches at the right height.

Leave 100–120 cm between the upper bench and the ceiling.
The height difference between the upper and lower bench is usually 40–45 cm.
The upper bench is usually 55–60 cm deep.
Allow at least 60 cm of seating per person.
Check the safety distances between the heater and the benches in the heater manufacturer's instructions.

Leave 100–120 cm between the upper bench and the ceiling.

Fix the boards from below

Let the boards acclimatise in the sauna for 1–2 weeks before installation.
Support the benches properly. Fix the brackets to the wall battens or to extra supports installed behind the panels. Support long benches in the middle as well.
Leave a gap between the bench and the wall (about 5–10 mm) and between the boards, so air can circulate and the wood can dry.
Always fix the boards from below with stainless steel screws, so no screw heads end up on the seating surface where they would get hot. Pre-drill the holes so the boards do not split.

Screws from below, gaps between the boards.

Always treat the benches before use

Temperature and humidity in the sauna change quickly and a lot, so benches always need a surface treatment. Treat them with paraffin oil or sauna wax before the first use. For thermally modified benches we recommend paraffin oil only.

Paraffin oil soaks into the wood, makes it harder for water to penetrate and repels dirt. It slightly deepens the tone of the wood.
Test the oil on an inconspicuous spot first to see how the tone changes.
Apply the oil with a sponge or cloth along the grain, and treat the board ends too. The surface is ready for the sauna after about 12 hours.

Paraffin oil or sauna wax before the first use.

How to keep the benches beautiful

Dry the sauna after every use. Lift removable bench sections upright and keep the heater on for about half an hour with the door closed and the vent open.
Use a bench towel, and take textiles out of the sauna afterwards.
Do not hose down the benches after every use. Wash them 1–4 times a year depending on use, with a mild sauna cleaner and a soft brush along the grain.
Renew the oil treatment 1–5 times a year, when the surface starts to look dull.
Tighten the screws once or twice during the first year, as the wood shrinks.

Benches that dry well stay beautiful and last a long time.

Choose your bench wood with a sample

We send samples of bench boards so you can see the tone in your own sauna. Contact our sales team or read more about our wood species.

Wood cladding for saunas and interiors – selection guide | Lauta.fi

juho.kallonen@lauta.fi (Juho Kallonen) — Sun, 01 Nov 2026 15:53:33 GMT

When the sauna, bathroom and living spaces are clad with the same wood, a home or holiday house looks calm and consistent. Conditions in these spaces vary a lot, though: in the sauna, temperature and humidity change quickly, while in the living room the air is stable and dry in winter. This article explains how to choose the wood species, panel and surface treatment so that the same surface works in every space.

1. Know what each space demands

We divide interiors into four applications, and every product we make is labelled for each of them:

Dry interiors: living rooms, bedrooms, hallways and lobbies. Almost any species works, and you can choose the finish freely by appearance.
Wet room ceilings: moisture rises to the ceiling, but water does not splash directly onto the surface.
Wet room walls: a more demanding application, where the wood has to withstand splashes and rapid changes in humidity.
Saunas: the toughest conditions. The wood must be resin-free and conduct heat slowly.

The labels also show whether the wood can be used as it is or whether surface treatment is recommended. They are based on our wood species suitability table.

2. Choose a species that works in every space

If you want the same species from the sauna to the living room, choose it for the most demanding space – the sauna.

Spruce is light and affordable. In the sauna it needs a sauna protective finish or paraffin oil.
Aspen is resin-free, almost knot-free and light. It creates a fresh, bright feel and has a mild scent.
Alder is resin-free with a warm reddish-brown tone that darkens beautifully over time.
Western red cedar is a light, aromatic speciality wood that suits saunas.
Thermally modified species, such as thermo aspen, thermo alder, thermo pine and thermally modified radiata pine, are dimensionally stable and dark. They are especially well suited to wet rooms and saunas.

Remember two exceptions: thermally modified aspen is not suitable for a continuously heated sauna – choose thermally modified alder or thermally modified radiata pine instead, which we offer in a wide range – and untreated pine releases resin in the sauna. The tone changes over time: light wood darkens and dark thermally modified wood lightens.

3. Choose the profile, width and direction

Narrow panels create a rhythmic surface, wide panels a calm one. A sharp-edged profile casts strong shadows, a rounder one gives a softer look. A batten panel looks like separate battens but installs like a panel.

Different profiles of the same species can set spaces apart without breaking the whole.

Consistency comes from running the panels in the same direction from one space to the next. Or make the sauna a space of its own by switching from horizontal to vertical panels. On ceilings, run the panels in the direction of the light.

Panels can be installed horizontally, vertically or diagonally.

4. Match the finish to the space

The same wood can get a different treatment in each space, as long as the tone stays the same:

Sauna: spruce, aspen and alder with a sauna protective finish or paraffin oil; thermally modified species with paraffin oil. A sauna protective finish can also be tinted.
Wet rooms: a moisture-resistant finish made for wet rooms.
Dry interiors: paint, oil, wax or lacquer. A semi-transparent finish leaves the grain visible; opaque paint gives an even colour. For panelled ceilings, choose a matt paint.

Good to know: light wood darkens and yellows in daylight. To keep a light tone, choose a white-pigmented or UV-protective, non-yellowing product.

You can also order the panels pre-finished. When the treatment is applied at the factory before installation, the tongues and edges are treated too, so no light stripes appear at the joints when the wood shrinks in winter.

Treat new wood before fixing it, so the tongues and ends are treated as well.

5. Install it right and the surface stays neat

Let the panels acclimatise in the installation space for 1–2 weeks at about +20 °C and 40–60% relative humidity.
Allow 10–15% for waste and choose panels at least 5 cm longer than you need.
Fix the battens at right angles to the panels, at most 600 mm apart.
Allow for movement: about 10 mm between the panel and the wall in dry spaces, about 15 mm in the sauna.
In the sauna, install horizontal panels tongue up, leave a ventilation gap behind the panels and always use stainless steel fixings.

Vertical battens for horizontal panels, horizontal battens for vertical panels. Face nailing is the easiest and most secure method. Panels with a concealed-nail tongue are fixed through the groove.

Example combinations

Light and bright: aspen panel 15x90 STS4 for the sauna and bathroom ceiling, and the same panel with a white semi-transparent finish in the living room.
Warm and reddish: alder panel 15x120 STS4 for the sauna and bathroom.
Dark and modern: thermo pine panel 15x118 STS4 for the sauna and wet rooms, with light-painted spruce panels in dry spaces for contrast.

Need help choosing?

We send samples of wood species and finishes so you can see the tones in your own light. Contact our sales team, explore our wood species or browse the product catalogue.

Sauna panels for hotels and spas – selection guide | Lauta.fi

juho.kallonen@lauta.fi (Juho Kallonen) — Sun, 01 Nov 2026 15:53:31 GMT

A sauna in a hotel, spa or holiday resort is hot for many hours a day, and more people sit on its benches in a week than in a home sauna in a year. That is why it pays to choose the wood species, profile, surface treatment and maintenance plan for the interior cladding together, at the design stage. This guide covers the questions developers, architects and sauna builders ask us most often.

How is a hotel sauna different from a home sauna?

In a hospitality sauna, the wood is put under strain for three reasons:

Operating hours. The sauna may be heated all day or even continuously. Temperature and humidity change quickly every time water is thrown on the stones.
Cleaning. Surfaces are washed more often than at home, so the finish has to withstand washing and the wood has to dry quickly.
Appearance. The sauna has to look clean and tidy year after year, and the same wooden look often continues from the washrooms to the lobby.

Choose the wood species for the way the sauna is used

Wood species for saunas are free of resin, or have had the resin removed by thermal modification. They conduct heat slowly, so the surface does not get too hot against the skin.

Spruce is a light, affordable standard choice for sauna walls and ceilings. A sauna protective finish protects it against moisture and dirt.
Aspen and alder are resin-free hardwoods. Aspen is almost white and very even; alder has a warm reddish-brown tone.
Thermally modified species, such as thermo pine, thermo aspen, thermo alder and thermally modified radiata pine, are dimensionally stable and dark. Thermal modification is carried out at high temperature using steam, and it removes the resin from the wood.

Thermally modified radiata pine: newly installed radiata pine can have a strong smell at first. Ventilate the sauna well before opening it to guests, and the smell will fade.

Avoid untreated pine. Resin seeps out when the surface heats up.

See our wood species suitability table for which species suit which spaces.

Profile and direction define the look

Narrow panels create a rhythmic surface, wide panels a calm one. You can combine different widths and species in the same space. A batten panel looks like separate battens but installs like a panel, which speeds up cladding large surfaces such as ceilings.

The profile determines how light and shadow fall on the surface.

Panels can be installed horizontally, vertically or diagonally, and you can change direction within a surface. On ceilings, run the panels in the direction of the light so the joints are less visible.

Diagonal, vertical or horizontal – the direction changes the feel of the room.

Factory finishing saves time on site

For a large project, order the panels with the surface treatment already applied. We treat the wood in our own industrial paint shop right after planing, while the surface is open and absorbs the finish effectively.

Sauna protective finish helps sauna surfaces withstand high temperatures and humidity, and keeps them easier to clean. It can also be tinted.
Semi-transparent stain gives the wood a tone but leaves the grain visible. Use it to carry the same tone into changing rooms and the lobby.
Tongues and edges are treated too. When the wood shrinks in the dry season, no untreated stripes appear at the joints.
An even finish across the whole project. Under controlled conditions every panel gets the same treatment, so the tone stays consistent from floor to floor.

We treat batches of at least 500 metres at a time, which suits the quantities of hotel and spa projects. Spaces outside the sauna, such as corridors and lobbies, may have stricter fire safety requirements. With fire-retardant treatment, a wooden surface reaches fire class B-s1, d0 – the highest class possible for wood building products. Fire-retardant treatment cannot be used inside the sauna itself, as there is no fire-retardant product suited to sauna conditions.

When panels are treated before installation, the tongues get treated too.

One wooden look from the sauna to the lobby

When you use the same wood species in the sauna, washrooms and lobby, the spaces connect naturally. In the sauna, the panels are treated with a sauna protective finish or paraffin oil; in dry spaces with a semi-transparent or opaque finish. Match the benches to the tone, width and direction of the wall panels. Bench boards and battens of the same species also work for benches, shelves and other furniture.

Example combinations:

Light and fresh: aspen panel 15x90 STS4 or aspen batten panel 15x90 with aspen bench board 28x120.
Warm and reddish: alder panel 15x120 STS4.
Dark and dimensionally stable: thermo pine panel 15x118 STS4 with thermo pine bench board 26x118 SHP.
Pre-finished spruce: spruce panel 15x120 STS4 with tinted sauna protective finish.

Installation for heavy use

Let the panels acclimatise in the installation space for 1–2 weeks before installation, at about +20 °C and 40–60% relative humidity. Wet work such as levelling and tiling raises humidity, so do not store panels in the same space while it is going on.
Leave a ventilation gap between the panels and the vapour barrier. Leave a small gap at the bottom of the wall and leave out mouldings at the wall-ceiling joint so air can circulate behind the panels.
Allow for movement. Wood moves more in a sauna, so leave a gap of about 15 mm between the panel and the adjacent wall.
Install horizontal panels tongue up so moisture cannot get into the groove.
Use stainless steel fixings whatever the species. Fix thermally modified panels with a nail gun so they do not split.
Fix bench supports to the wall battens or to extra supports behind the panels – never to the panelling alone.

Battens always run at right angles to the panels, at most 600 mm apart.

Maintenance in heavy use

A sauna that dries well lasts longest. Train your staff in these routines:

Dry the sauna after every period of use. Keep the heater on for at least 30 minutes, with the door closed, the exhaust vent open and mechanical ventilation running.
Do not hose down the walls every day. Wash the panels according to use – more often when the sauna is busy. Use a mild sauna cleaner and a soft brush along the grain. Do not use chlorine-based products or a pressure washer.
Renew the surface treatment in time, preferably every year. Spruce, aspen and alder: sauna protective finish or paraffin oil. Thermally modified species: paraffin oil.
Treat the benches with paraffin oil or sauna wax. Benches in a busy sauna need treatment more often.

When the sauna dries after use, the wood stays beautiful for years.

Checklist for designers

Is the sauna continuously heated? If so, choose the species accordingly.
Which species and tone continue from the sauna to the washrooms and lobby?
Profile, width and direction for walls and ceilings.
Factory finishing: sauna protective finish, semi-transparent stain, fire-retardant treatment for spaces outside the sauna.
Quantity plus 10–15% waste allowance.
Fixings, ventilation gaps and bench supports.
Maintenance instructions for staff.

Talk to our sales team

We supply wood for visible surfaces to contractors, sauna builders and designers in Finland and abroad. We send samples of wood species and finishes, and help you calculate quantities. Contact our sales team or browse the product catalogue.