How to Clean a Sauna: A Complete Cleaning and Maintenance Guide

A home sauna does not need complicated maintenance, but it does need consistent drying, gentle cleaning and periodic checks of its timber, heater and other components.

For most domestic saunas, the best routine is simple: use a clean towel on the bench, wipe away visible moisture after your session, allow the sauna to dry properly and carry out a deeper clean periodically rather than aggressively scrubbing the timber after every use. Harvia's UK support guidance recommends after-use wiping and drying, with a more thorough clean around one to three times a year for a family sauna.

Cleaning needs will increase if the sauna is used very frequently or by several people.

This guide explains how to clean a sauna properly, which products to use, how to care for wooden benches and sauna stones, and the extra maintenance required for infrared and outdoor saunas.

How Often Should You Clean a Home Sauna?

A home sauna should receive light care after every use and a more thorough clean periodically. There is no need to deep-clean the timber after every sauna session.

Harvia recommends removing wet items, wiping away moisture and helping the sauna dry after bathing. Its current UK guidance says a family sauna typically needs a more thorough wash around one to three times a year. Sauna from Finland similarly recommends after-use care combined with deeper domestic cleaning around once or twice annually.

A practical home routine looks like this:

Frequency	Maintenance
After each use	Remove towels and water, wipe obvious moisture or marks, ventilate and dry the cabin
Regularly	Sweep or vacuum loose debris, check benches and wipe high-contact surfaces
Periodically	Clean benches, backrests, walls and floor more thoroughly with a suitable sauna cleaner
At least annually	Inspect traditional sauna stones, heater condition, fixings, ventilation and general timber condition
Seasonally for outdoor saunas	Inspect exterior timber, roof, seals, base and signs of weather exposure

Treat this as a starting point rather than a rigid schedule. A sauna being used daily by several people will need more cleaning than one used once a week by one person.

What Should You Do After Every Sauna Session?

The easiest way to keep a sauna clean is to stop sweat, water and dirt from remaining on the timber for long periods.

1. Remove towels and wet accessories

Take out bench towels, mats and other damp textiles rather than leaving them inside the closed sauna.

Empty the sauna bucket if it will not be used again soon and allow accessories to dry.

2. Wipe away moisture and visible marks

Use a clean, damp cloth on areas such as the benches and backrests where necessary.

Harvia recommends wiping away water droplets after bathing rather than allowing moisture to sit on the timber.

3. Let the sauna dry thoroughly

Drying is one of the most important parts of sauna maintenance.

Harvia advises using the remaining heat from the sauna and sufficient ventilation to dry wooden parts after bathing. Its guidance also recommends opening the air vent and leaving the door partly open.

The aim is simple: do not close a damp sauna and leave moisture trapped inside.

The supplied Sauna Menthol guide to sauna cleaning and maintenance likewise puts ventilation at the centre of its after-use routine.

What Should You Use to Clean a Sauna?

Use warm water, a soft cloth or brush and a cleaning product specifically suitable for sauna surfaces when a deeper clean is required.

Sauna timber experiences repeated heating and cooling, so this is not the place to automatically reach for the strongest household cleaning product available.

Sauna from Finland recommends paying attention to the pH of the cleaner and identifies weakly alkaline cleaners in the pH 8.1 to 10 range as appropriate across sauna facilities. Harvia also recommends a suitable cleaning solution and a soft brush for wooden benches.

CenturaHeat stocks Supi Saunapesu Sauna Cleaning Agent, a Tikkurila cleaner designed for wooden, metal and tiled sauna surfaces. Tikkurila states that it removes limescale without chlorine and is intended specifically for saunas and other humid rooms.

Always follow the cleaner's instructions and your sauna manufacturer's care guidance rather than assuming that one concentration or method suits every surface.

Can you use bleach to clean a sauna?

Avoid introducing chlorine-based products unless the manufacturer of the sauna and cleaning product specifically says otherwise.

For example, Tikkurila explicitly states that Supi Saunapesu must not be used together with products containing chlorine.

Never mix cleaning chemicals.

How to Clean a Sauna Step by Step

Step 1: Switch the sauna off and let it cool

Carry out proper cleaning when the sauna and heater are cool.

If you are going anywhere near the heater, stones or electrical components, switch the equipment off first. Harvia specifically instructs owners to ensure the heater is cool and off before removing and inspecting sauna stones.

Step 2: Remove loose dirt

Take out removable towels, accessories and floor mats.

Sweep or carefully vacuum dust, hair and loose debris from:

• the floor
• beneath the benches
• corners
• around bench supports
• doorways
• accessible ventilation openings.

Pay particular attention to areas beneath and around benches. Sauna from Finland identifies lower benches, floors and surfaces people regularly lean against as areas that often require extra attention.

Step 3: Clean the benches and backrests

Sauna benches receive the most direct contact with perspiration and skin, so they normally require the most attention.

Use warm water and a suitable sauna cleaning solution with a soft cloth or brush. Harvia recommends brushing wooden benches in the direction of the wood grain, rinsing away cleaning product and thoroughly drying the sauna afterwards.

Avoid soaking the timber unnecessarily.

Cleaning should lift dirt from the surface, not saturate the wood.

Step 4: Wipe walls and other timber surfaces

Walls generally receive less direct contact than benches, so they may not require the same amount of scrubbing.

Use a damp rather than dripping-wet cloth and concentrate on visible marks, lower wall sections and areas people lean against.

The exact care method can vary depending on whether the timber is untreated, oiled, waxed or otherwise finished, so follow your sauna's instructions before applying any treatment.

Step 5: Clean the floor

Sweep or vacuum loose debris before washing.

If your sauna has a tiled or other non-timber floor, use a cleaner suitable for that surface. If it includes a drain, check that the drain remains clear.

The Saunamo sauna cleaning and maintenance guide specifically recommends checking and cleaning sauna drains as part of the cleaning routine where fitted.

Step 6: Clean the glass

Wipe sauna doors and glass panels using a product suitable for the glass and the manufacturer's instructions.

Where a cleaner is being used near timber, infrared emitters, controls or other electrical components, apply it to your cloth rather than spraying indiscriminately around the cabin.

Step 7: Rinse where required

If the product instructions require rinsing, remove all cleaner residue from the relevant surfaces.

Do not leave unnecessary detergent behind on surfaces that will later be heated.

Step 8: Dry the sauna completely

Drying is the final part of cleaning, not an optional extra.

Use clean towels to remove excess water where necessary and ventilate the sauna thoroughly.

Harvia recommends drying the sauna using heat and sufficient ventilation after a deeper clean.

How Do You Clean Wooden Sauna Benches?

Clean wooden sauna benches gently with warm water, a sauna-suitable cleaning product and a soft brush or cloth. Work with the grain of the timber and allow the benches to dry thoroughly afterwards.

Do not attack stains with an aggressive scourer or flood the wood with water.

For ingrained marks that ordinary cleaning does not remove, light sanding may sometimes be appropriate. Both Harvia and Sauna from Finland discuss gentle sanding as a way of refreshing sauna timber.

Only sand if the construction and finish of your particular sauna allow it. Sand in the direction of the grain and remove all dust afterwards.

How do you prevent sweat stains on sauna benches?

Prevention is much easier than repeatedly removing marks.

Use a clean sauna towel or bench cover between your body and the timber. Sauna from Finland specifically recommends bench covers because they protect porous wood and can be washed far more easily than the benches themselves.

Showering before entering can also reduce the amount of cosmetics, body oils and outside dirt transferred onto the timber.

Should You Oil or Wax Sauna Wood?

Some untreated sauna benches can be protected with a suitable sauna-specific paraffin oil or other approved treatment, but not every surface should automatically be oiled or waxed.

Harvia states that its paraffin oil reduces the amount of moisture and dirt absorbed by wooden benches and recommends treatment once or twice per year when cleaning for suitable timber. Tikkurila similarly offers paraffin-oil protection specifically for untreated or previously oiled sauna benches.

However, walls, benches and exterior timber may all have different finishes.

Do not use ordinary furniture polish, decking oil, varnish or another wood treatment inside a sauna unless your sauna manufacturer confirms it is appropriate for that specific surface.

Cleaning and protecting wood are two separate jobs.

How Do You Maintain Sauna Heater Stones?

If your traditional sauna uses stones, their condition should form part of your maintenance routine.

Harvia recommends checking sauna stones at least once a year and replacing stones that have begun to break down, crumble or become discoloured.

Before touching them:

1. Switch the heater off.
2. Allow the heater and stones to become completely cool.
3. Remove the stones according to your heater instructions.
4. Check for cracking, crumbling or deterioration.
5. Remove stone debris from the heater.
6. Wash sound stones where the manufacturer's instructions allow it.
7. Allow them to dry.
8. Re-stack them according to the heater manual.

Stone arrangement matters because air must be able to move through the heater. Harvia warns that deteriorated or overly tightly packed stones can restrict airflow and place additional heat stress on electric heating elements.

Do not simply add new stones on top of an old compacted pile indefinitely.

How Do You Clean a Traditional Sauna Heater?

Cleaning the outside of an electric sauna heater is different from dismantling or repairing it.

Once the heater is switched off and completely cool, visible exterior surfaces can be cleaned according to the manufacturer's instructions.

Limescale may build up where water repeatedly dries on heater surfaces. Harvia sells a dedicated heater cleaner for compatible acid-resistant surfaces and also provides specific decalcification guidance for suitable heaters.

Do not pour cleaning product into an electric heater or attempt to clean heating elements as though they were ordinary household surfaces.

If you see damaged components, persistent electrical faults or unusual deterioration, stop using the sauna and obtain appropriate technical advice.

Is Infrared Sauna Cleaning Different?

Yes, slightly. Infrared saunas often create less moisture than traditional saunas, but benches, flooring, glass and high-contact surfaces still need routine cleaning.

There are also infrared emitters and electrical components to consider.

Manufacturer guidance for infrared cabins commonly recommends light cleaning with a damp cloth, paying particular attention to benches and other high-contact surfaces while avoiding unnecessary spraying around heaters and electrical components.

For an infrared sauna:

• wipe benches after use where necessary
• keep the floor free from dust and debris
• clean glass separately
• keep ventilation openings clear
• avoid spraying liquids directly onto infrared emitters or controls
• follow the model's instructions for cleaning heating panels
• let the cabin dry and air between sessions.

Do not assume that because an infrared sauna uses drier heat it never needs cleaning.

How Do You Prevent Mould and Musty Smells in a Sauna?

The most important defence against mould and musty odours is allowing the sauna to dry thoroughly between uses.

Moisture left trapped in timber or poorly ventilated spaces creates conditions in which mould can become a problem.

Both Saunamo and Sauna Menthol put ventilation and drying at the centre of mould and odour prevention.

Good habits include:

• removing wet towels after every session
• wiping standing water
• leaving appropriate ventilation open
• allowing the cabin to dry before closing it for long periods
• keeping vents free from dust
• checking underneath benches
• investigating persistent damp rather than masking its smell.

A musty smell that repeatedly returns after cleaning may indicate a moisture or ventilation problem rather than simply a dirty surface.

If you find extensive mould, soft or damaged timber, leaks or persistent damp, identify and address the underlying cause rather than repeatedly applying cleaner.

How Should You Maintain an Outdoor Sauna?

Outdoor saunas need the same interior cleaning as indoor models plus regular checks of the exterior.

The Saunamo maintenance guide highlights exterior timber, roofing, drainage, foundations and weather exposure as additional considerations for outdoor sauna owners.

For an outdoor sauna, periodically check:

• the roof and weatherproof covering
• exterior timber finish
• doors and seals
• the base and drainage around the sauna
• exposed fixings
• signs of standing water
• leaves and debris
• any visible cracking or deterioration.

CenturaHeat's own comparison of indoor and outdoor sauna ownership also notes that outdoor models require additional attention because of weather exposure, while indoor models avoid much of that exterior maintenance.

Always use an exterior treatment suitable for your particular sauna rather than applying a generic decking product without checking compatibility.

What Are the Most Common Sauna Cleaning Mistakes?

Using too much water

Sauna timber should be cleaned, not flooded.

Use the amount of moisture necessary for the job and dry everything thoroughly afterwards.

Reaching for a strong household chemical

A stronger cleaner is not automatically a better sauna cleaner.

Use products designed or approved for the relevant sauna material and follow their instructions.

Forgetting underneath the benches

Dirt and moisture are not limited to the surfaces you can see easily. Sauna from Finland specifically recommends cleaning the underside of benches as part of maintaining wooden sauna fixtures.

Closing the sauna while it is still damp

This removes the airflow needed for drying.

Ignoring the heater stones

Traditional sauna maintenance is not only about timber. Stones gradually deteriorate and should be inspected and re-stacked periodically.

Spraying cleaners around electrical components

Apply cleaners carefully and follow the sauna manufacturer's instructions for control panels, infrared emitters and heaters.

Using unsuitable wood treatments

Only use oils, waxes or other finishes specifically approved for the surface being treated.

Is a Home Sauna Difficult to Maintain?

For most domestic users, no. The majority of sauna care comes down to a few small habits after each session rather than frequent intensive cleaning.

Harvia and Sauna from Finland both recommend routine after-use care combined with only periodic deeper cleaning for a normal home sauna.

That makes maintenance worth considering before purchasing, but it should not generally be viewed in the same way as maintaining a water-filled spa system.

If you are currently researching ownership, you can compare traditional, infrared, indoor and outdoor options in the CenturaHeat home sauna collection. Different designs have slightly different care requirements, so it is worth considering maintenance alongside size, location and heating type before buying.

A Simple Sauna Maintenance Checklist

For most home sauna owners, the routine can be reduced to five principles:

1. Protect the benches. Sit on a clean towel or sauna cover.
2. Keep it dry. Remove damp items and ventilate after use.
3. Clean gently. Use appropriate tools and sauna-safe products.
4. Inspect the equipment. Check traditional sauna stones and the visible condition of the heater periodically.
5. Follow the manual. Product-specific instructions take priority over generic advice.

If you need a cleaner made specifically for sauna surfaces, Centuraheat's Supi Saunapesu Sauna Cleaning Agent is suitable for wood, metal and tile sauna surfaces and is designed to remove limescale without chlorine.

Frequently Asked Questions

What is the best thing to clean a sauna with?

For routine cleaning, use warm water and a soft cloth or brush. When additional cleaning is needed, use a product specifically suitable for sauna surfaces and follow both the cleaner's instructions and your sauna manual. Sauna from Finland recommends weakly alkaline cleaning products for general sauna cleaning.

How often should I deep-clean my home sauna?

It depends on usage. Harvia's UK guidance recommends thorough cleaning of a family sauna around one to three times per year, while Sauna from Finland suggests roughly one or two thorough cleans annually alongside after-use care. Heavily used saunas may require cleaning more frequently.

Can I pressure-wash the inside of a wooden sauna?

A pressure washer should not be treated as a normal method for cleaning sauna interiors. Specialist manufacturer KLAFS explicitly warns against high-pressure cleaning of its sauna timber because excess water and pressure can damage the wood. Follow the instructions supplied with your sauna.

How do I remove sweat stains from sauna benches?

Begin with warm water and a sauna-safe cleaning product. Gently brush along the grain. If a stain remains and your sauna's care instructions permit it, light sanding can refresh the timber surface. Harvia includes light sanding among its maintenance options for sauna wood.

How often should sauna stones be replaced?

There is no universal replacement date because deterioration depends on the stones, heater and frequency of use. Harvia recommends inspecting and re-stacking stones at least annually and replacing individual stones that crack, crumble or deteriorate rather than automatically discarding sound stones.

Why does my sauna smell musty?

A persistent musty smell can indicate that the sauna is not drying properly or that moisture is remaining in timber, underneath benches or elsewhere in the structure. Improve drying and ventilation, inspect hidden areas and investigate any source of persistent damp rather than simply covering the smell with fragrance.

Final Thoughts

Good sauna maintenance is mostly preventative.

Using a clean towel, wiping away moisture and allowing the sauna to dry after each session can reduce how much intensive cleaning is needed later. Periodic deeper cleaning then takes care of accumulated dirt, while checks of timber, ventilation, heaters and sauna stones help identify wear before it becomes a bigger problem.

Most importantly, treat the sauna as a specialist heated environment. Use appropriate cleaning products, avoid saturating wooden surfaces and follow the care instructions for your particular model.

If you already own a sauna and need a suitable cleaning product, CenturaHeat offers Supi Saunapesu Sauna Cleaning Agent for compatible wooden, metal and tiled sauna surfaces.

If you are researching sauna ownership, you can also browse CenturaHeat's range of home saunas, including indoor, outdoor, traditional and infrared options. For questions about the care requirements of a specific CenturaHeat model, contact the CenturaHeat team.

A sauna should be a space you look forward to using. A small amount of regular care helps keep it clean, dry and ready for the next session.