A wooden sauna absorbs everything. Steam, heat, the oils from your skin, the quiet repetition of each session. Over weeks and months, that accumulation becomes visible: a bench that has lost its warmth, a scent that has shifted from birch and cedar to something less inviting. Cleaning a wooden sauna is not just maintenance. It is how you keep the ritual alive.
In Finland, caring for the sauna is taken as seriously as the sauna itself. The wood is treated with attention, cleaned gently and oiled regularly, not because it is laborious but because a well-cared-for sauna rewards you every time you walk through the door. This guide covers everything you need to know: how often to clean, how to do it properly, what to avoid, and how to protect the wood so it stays beautiful for years.
Why Wooden Sauna Surfaces Need Special Care
Sauna wood lives in one of the most demanding environments imaginable. Temperatures swing from ambient to 80°C or higher. Humidity rises dramatically every session. Skin oils and sweat absorb into the grain. And all of this happens repeatedly, week after week.
Most common household cleaners are not designed for these conditions. Harsh chemicals can dry out and discolour the wood, strip its natural character, or leave residues that become unpleasant when heat activates them. The same goes for too much water: wood that is oversaturated can warp, develop mould in the cracks beneath bench slats, or simply break down faster than it should.
Sauna wood needs cleaners that are gentle enough to preserve the grain, strong enough to remove sweat and dirt, and formulated specifically for an environment defined by heat and steam. It then needs protection: an oil that nourishes without sealing, allowing the wood to breathe while shielding it from moisture and wear.
How Often Should You Clean a Sauna?
There are two kinds of sauna cleaning: what you do after every session, and the deeper ritual you perform a few times a year.
After each use, a quick wipe-down of benches, backrests and any surfaces that came into contact with skin will prevent sweat from settling into the wood and turning into the stains that are far harder to remove later. This takes only a few minutes and makes the deeper cleaning much easier when it comes.
A proper full clean (with a wood cleaner, brush, and thorough rinse) should happen two to four times a year, depending on how frequently the sauna is used. Regular sauna users, families and hospitality settings will naturally need to clean more often. After cleaning, treat the wood with care oil to restore its protection. How often you oil the wood depends on how dry or worn the benches look, but once or twice a year is a reasonable baseline for most saunas.
What You Need Before You Start
Before cleaning, let the sauna cool completely. Working on hot or even warm surfaces is harder on both you and the wood: the cleaner evaporates too fast, the wood pores are in a different state, and you lose control of the process. Let everything come to room temperature first.
You will need the sauna/ing Sauna Wood Cleaner (either the ready-to-use Spray for convenience, or the Concentrate if you are cleaning more frequently or covering a larger area), the sauna/ing Sauna Clean Brush, clean cotton cloths for wiping, and the sauna/ing Sauna Wood Care Oil for the finishing step. Avoid anything abrasive, any general household cleaning product, bleach, or pressure washers. The goal is gentle and thorough, not forceful.
Step 1: Clean the Wood
Start by removing any loose debris with a dry cloth or light sweep. Then moisten the wooden surfaces with clean water, working with the grain rather than across it. This opens the pores gently and prepares the surface to receive the cleaner.
For quick regular cleans, after each session or light use, the sauna/ing Sauna Wood Cleaner Spray applied directly to damp surfaces and worked in with the sauna/ing Sauna Clean Brush is all you need. Brush parallel to the grain, working along each bench slat, and pay particular attention to the undersides of the benches, where sweat collects and where bacteria and mould are most likely to develop if cleaning is neglected.
For deeper or larger-area cleans, the sauna/ing Sauna Wood Cleaner Concentrate is a smart choice. Dilute one part concentrate with four parts water to get 2.5 litres of cleaning solution from a single 500 ml bottle. It is the same gentle formula as the spray, in a more economical and sustainable format: less packaging, lower cost per use, and ideal for frequent sauna users and hospitality settings. Adjust the dilution based on how much cleaning is needed and how soiled the surfaces are.
Once you have brushed all surfaces, wipe away the residue with a clean damp cloth. Then rinse with fresh water. Never leave cleaner sitting on the wood. It must be fully removed before drying begins. Open the sauna door and vent the space thoroughly; wood that stays damp too long will suffer.
Step 2: Nourish and Protect with Wood Care Oil
Cleaning removes what should not be there. Oiling restores what the wood needs to stay resilient: a protective layer that shields against moisture, dirt and the physical demands of repeated heating and cooling.
This step should only be done on surfaces that are clean and completely dry. Oiling damp or dirty wood traps rather than protects. Once the sauna has aired out fully after cleaning, apply a thin, even coat of the sauna/ing Sauna Wood Care Oil to the benches and any other wooden surfaces using a lint-free cloth. Work it in with the grain and allow it to absorb for about fifteen minutes before wiping away any excess.
If the wood is particularly dry or has not been oiled in some time, a second coat after the first has absorbed will deepen the protection. After oiling, heat the sauna to around 60°C to help the oil fully bond with the wood, and wipe away any remaining excess with a clean cotton cloth before anyone sits on the benches.
The result should be wood that looks naturally richer, feels smooth to the touch, and has a quiet sheen without appearing varnished or sealed. The grain stays open, the character stays intact.
What to Avoid When Cleaning Sauna Wood
A few common mistakes will damage the wood or make the problem worse rather than better. Avoid pressure washers entirely: the force strips the grain and drives moisture into places it cannot escape from. Do not use bleach or general bathroom cleaners; they are too aggressive and often leave residues that smell unpleasant when heated. Do not use too much water at once, and never leave any cleaner to dry on the surface before rinsing.
Do not oil wood that has not been cleaned first, and never apply oil to a hot sauna or immediately before use: the oil needs time to absorb and bond before the sauna reaches full temperature. And always use clean brushes and cloths for each cleaning session; a brush that has accumulated old residue will redeposit it onto surfaces you are trying to clean.
The sauna/ing Sauna Clean & Care Collection
We developed the sauna/ing Sauna Clean & Care collection specifically for this purpose: products made in Finland, designed for wooden sauna surfaces, and formulated to work with the unique demands of the sauna environment rather than against them.
The cleaners are pH-neutral and phosphate-free, made with plant-based surfactants and biodegradable ingredients, and delicately scented with pure pine essential oil. They clean without stripping, and rinse without leaving residue. The care oil is a pure, colourless paraffin oil that nourishes and protects without altering the natural look or feel of the wood. The Finnish-made cleaning brush has natural fibre bristles and a long wooden handle that reaches into every corner, every gap between bench slats, every place where neglect tends to settle.
Used together, they make sauna care feel less like a chore and more like the ritual it was always meant to be.
A Sauna That Invites You Back
There is a particular quality to a well-maintained sauna. You notice it the moment the door opens: the wood is clean and bright, the air carries only warmth and whatever scent you have chosen for the stones, nothing accumulated or stale. The benches feel smooth under your hand. The space feels cared for.
That quality does not happen by accident. It comes from cleaning gently and consistently, from oiling before the wood has a chance to dry out, from paying attention to the undersides and the gaps and the corners that are easy to overlook. It comes from treating the sauna not as a room that needs maintenance but as a space worth preserving.
In Finland, the sauna is considered the most honest room in the house: a place where nothing is performed, everything is felt. A clean sauna honours that. It keeps the experience what it has always been, and what it should always remain.
