Guides

Western red cedar is an excellent sauna timber — very stable, low in density and naturally aromatic — and it is our principal timber. We also build with Canadian hemlock when a client wants a paler, almost scent-free room. Other species, such as aspen, alder, spruce and thermally modified timber, are widely used in saunas overseas and are compared here for reference. The right choice depends on the look you want, how the room will be used and whether the aroma of cedar suits you.

Knots are denser than the surrounding wood and often hold more resin. Denser wood transfers heat to your skin faster, so knots can feel noticeably hotter, and resin can soften and bleed at sauna temperatures. Benches, backrests and anything else you touch should be clear, knot-free timber.

Dense hardwoods such as spotted gum, jarrah and blackbutt are more than twice as dense as western red cedar, so they transfer heat to skin much more readily and are not suited to benches or hot-room linings. They work well outside the hot room — on exterior cladding, decks, change areas and cold-plunge surrounds.

Not inside the hot room. Varnish and lacquer are unsuitable at sauna temperatures. Many manufacturers recommend treating benches with a sauna-specific paraffin oil or wax to reduce staining, and leaving walls untreated or using only products made for saunas. Always follow the timber supplier's and heater manufacturer's instructions.

Yes. Thermally modified timber has a mild, smoky scent. It fades over time, and the ThermoWood industry handbook says it eventually becomes hard to notice except close up, although some makers say it never disappears entirely. If you are sensitive to scent, try a sample in a warm room before committing.

All sauna timber darkens with use, and pale benches show sweat and water marks most. Using towels on benches, drying the room after each session and occasional light sanding keep benches looking good. Darker timbers, including thermally modified species, hide marks more readily.

The lowest-density, driest, knot-free boards. Abachi, western red cedar and eastern white cedar are among the lightest sauna timbers, with spruce, aspen, alder and hemlock somewhat denser. Thermally modified timber transfers heat more slowly than the same untreated species. In practice, a clear grade and good drying matter as much as the species.

They are related but different species. Western red cedar (Thuja plicata) comes from western North America and has warm brown tones and a strong aroma. Eastern white cedar (Thuja occidentalis) comes from north-eastern North America; it is paler, with a milder scent and frequent small knots. Both are light, stable and decay-resistant.

Yes, particularly for walls and ceilings. Clear hemlock is pale, even and almost odourless, which suits people who prefer no scent. It is denser and moves more with moisture than cedar, so lighter species are usually preferred for benches. Ask for the botanical name, because two species are sold as Canadian hemlock.

Mostly because of the scent. Western red cedar has a strong, lingering aroma that many people enjoy and some find overpowering. It is also soft, so benches dent more easily under heavy use. If either is a concern, aspen, alder, hemlock or a thermally modified species may suit better.

It is more stable, darker and resin-free, and it hides marks better, which makes it popular for busy rooms. It is also more brittle, is not termite-resistant and has a mild smoky scent. Natural aspen is paler, odourless and shows marks more readily. Neither is better in every case.

No. Western red cedar is Thuja plicata, from western North America. True cedars belong to the genus Cedrus, and Australian red cedar (Toona ciliata) is a different tree again, in the mahogany family. "Canadian red cedar" and "Canadian cedar" are trade names for western red cedar.

We don't recommend it. Knots are denser than the surrounding wood, so they pass heat to the skin faster and can feel like hot spots. Western red cedar is described as resin-free, so resin bleed is less of a concern than with pine or spruce, but the density point still applies. Use a clear grade for benches, backrests and headrests, and keep knotty boards for walls and ceilings.

Australian timber references, WoodSolutions and the Queensland Government, rate western red cedar heartwood as resistant to termites. The rating applies to heartwood only. Termite management for the building structure and, on outdoor saunas, the base and subfloor remains a matter for the builder and certifier.

Usually from iron. Western red cedar reacts with iron to leave blue-black stains, and damp cedar is corrosive to iron and copper. Fixings should be stainless steel or another non-staining type. Tan or brown marks are a different thing, caused by water drawing the timber's natural extractives to the surface.

Not with varnish or lacquer. Walls and ceilings can be left unfinished. Benches can be treated with a sauna-specific paraffin oil a few times a year, or with a sauna wax, but not both on the same surface. Oil deepens the colour, so test it on the underside of a board first.

Hemlock has no characteristic scent, which is the main reason people choose it. A hemlock room smells of warm timber and very little else, whereas western red cedar has a strong, lingering aroma.

A little. Published densities for western hemlock run from about 430 to 505 kg/m³, against roughly 340 to 380 kg/m³ for western red cedar, and denser timber passes heat to the skin faster. Clear hemlock benches are used by some manufacturers, but where the lightest possible bench matters, cedar or another low-density timber is the better choice.

Sauna hemlock is normally sold as a clear, knot-free grade, but that is a grade, not a property of the species. Construction-grade hemlock can be knotty. Specify a clear grade and the botanical name on the order.

No. WoodSolutions, the Australian timber industry reference, rates western hemlock as not resistant to termites, with durability Class 4 above and in ground. For outdoor saunas in Queensland that matters for any hemlock outside the hot room, and termite management of the structure is a matter for the builder and certifier.

No. The timber is heated to roughly 180–220 °C in a low-oxygen atmosphere, with steam in the ThermoWood process, and no chemicals are added. The heat changes the wood itself, which is why the effect runs right through the board.

No. The ThermoWood Handbook says test results show it is unable to resist termite attack, and Lunawood, a Finnish producer, states plainly that its timber is not termite-resistant. Its improved decay resistance does not extend to termites, which matters in Queensland.

It fades but does not disappear completely. Thermally modified timber has a mild, smoky scent that Thermory says weakens over time but never fully goes. Heating the room with good airing speeds the fading. If you are sensitive to smells, try a warmed sample first.

No. It is more stable, but it is more brittle. ThermoWood tests show splitting strength falling by 30–40%, and bending strength drops at the higher treatment level. Benches need adequate board thickness, supported spans, rounded edges and sealed ends, and the material is not used structurally.

Most of the saunas we build are lined in western red cedar, and we sometimes use Canadian hemlock. Thermally modified timber is an established material in European saunas and you may come across it when researching. If you are interested in it for your project, talk to us about supply and detailing.

Yes. Clear aspen is light, resin-free and close to knot-free in sauna grades, and Finnish building guidance lists it among the recommended bench timbers. Its main drawback is that the pale natural timber shows sweat and water marks, so towels, regular cleaning and occasional oiling matter.

Thermo-aspen is the same species heated to around 185–215 °C in a low-oxygen kiln. It turns golden to mid-brown, becomes much more stable and transfers heat a little more slowly. It is also more brittle, has a mild smoky scent that never fully disappears, and needs its bench ends sealed.

Natural aspen has no characteristic scent, which suits people who find cedar too strong. Thermally modified aspen has a faint smoky note that fades over time.

No. The ThermoWood Handbook and the manufacturer Lunawood both state that thermally modified timber does not resist termites. We found no Australian termite rating for natural aspen either, which is rated non-durable and susceptible to insects.

Botanically, alder is a hardwood in the birch family, even though some suppliers describe it as a softwood. It is still a light timber suited to sauna benches.

It can be slightly warmer to the touch. Published densities for black alder range from about 380 to 600 kg/m³, typically around 490, against about 450 for aspen and about 340–380 for western red cedar. In a clear, well-dried board the difference is modest.

Thermal modification makes alder much more stable and gives it a dark, even colour that hides sweat and water marks. The trade-offs are greater brittleness, so bench ends must be sealed, and a mild smoky scent.

Yes. Alder darkens and reddens with age, and sauna paraffin oil deepens the tone further. If you want a very pale interior that stays pale, alder is not the right choice.

Yes. They are trade names for Triplochiton scleroxylon, a West and Central African hardwood. It is also sold as samba and wawa. Asking for the botanical name avoids confusion.

They are very similar. Abachi averages about 380 kg/m³ and western red cedar about 340–380 kg/m³, so both are among the lightest sauna timbers. We found no direct measurement showing one feels cooler than the other.

Abachi dust is a documented occupational sensitiser for people who saw and sand it, including sauna builders, so workshops need dust extraction and respiratory protection. The evidence concerns workers, not people using a finished sauna.

Possibly, but not easily. None of the Australian sauna timber suppliers in our research listed it. If you want abachi, it is worth confirming supply and certification before the design is finalised.

It is not the usual choice. Finnish guidance includes pale, low-resin spruce among bench timbers, but most manufacturers prefer aspen, alder or abachi for seats because spruce is usually knotty and its knots can bleed resin in the heat. Spruce is well suited to bench frames, where any resin is out of sight.

For linings, yes. Finnish sources prefer spruce because its resin content is considerably lower than pine's. Untreated pine is generally avoided in hot rooms because of resin.

Spruce that has been thermally modified at around 190–212 °C without chemicals. It is darker, much more stable and resin-free, but more brittle and with a mild smoky scent. Like all thermally modified timber, it is not termite-resistant.

It is a trade name. European or Nordic whitewood is usually Norway spruce, but the name can also cover European silver fir, so ask for the botanical name.

Hot air is lighter than cool air, so it rises and gathers under the ceiling while cooler air settles towards the floor. The difference is large. In a 2026 study of four Finnish saunas in normal use, the air averaged about 51 °C at sitting height and about 69 °C at 1.73 m. The top bench puts you in the hotter layer; the lower bench is cooler and works mainly as a foot rest and a gentler seat.

Harvia recommends about 1,100 to 1,200 mm between the upper bench and the ceiling, and notes that less will do if the bathers are short. Finnish Sauna Society and Saunologia guidance gives 1,000 to 1,200 mm. Heater manuals can add their own limits, so the manual for the selected heater has the final say.

It is a Finnish rule of thumb, attributed to the ethnologist Sakari Pälsi and restated by the Finnish Sauna Society, that a bather's feet should rest above the top of the heater stones, ideally by about 100 to 200 mm, so the heat feels even from head to toe. It comes from naturally ventilated saunas, and heater design and ventilation can change the result, so it is a design principle rather than a universal law.

Harvia suggests at least 500 mm for the upper bench and 600 mm or more if you want to lie down or lift your feet up. Finnish guidance gives about 450 to 600 mm for sitting. A lower bench used mainly for feet can be shallower. The right depth depends on how the room will be used.

About 600 mm of bench length per seated adult is the figure Harvia and Finnish sources both use. To lie down, Finnish guidance suggests about 1,800 to 2,000 mm of bench.

They can be the same species, but not always the same grade. Skin rests on a bench for minutes at a time, so bench timber needs to be low in density, free of knots and free of resin. Knots are denser than the surrounding wood, so they feel hotter, and resin can soften and bleed in the heat. Walls can take knotty grades if you like the look; benches should be clear.

Western red cedar is our principal timber, and we use clear grades wherever skin touches, which includes benches and backrests. We sometimes use Canadian hemlock where a paler, almost scent-free room is wanted.

No. Metal conducts heat far faster than timber, so an exposed screw head can become uncomfortably hot. Harvia's guidance is to fasten benches from below, and fixings should be stainless steel or another non-staining type, because iron reacts with cedar and stains it dark.

Generally no. Some manufacturers prohibit benches over the heater outright, and every heater has its own safety distances to benches, walls and ceiling. The manual for the selected model governs.

It is good practice. Benches that lift off their supports, or sections that lift out, make it easier to clean under them, dry the room thoroughly and replace a worn board. Harvia's standard bench sets, for example, rest on wall-mounted supports and are held with locking pieces underneath.

Low and indirect is the safest and most comfortable approach. Light concealed beneath benches, behind backrests or along the bench edges shows the steps and floor without glare. Harvia's North American manuals say lights placed low last longer and call under-bench positions ideal, and they ask that lights not be fitted above the heater or over the upper benches.

Only products made and rated for sauna use, installed where their rating allows. Ordinary household strips are not designed for sauna temperatures. Even purpose-made sauna strips have limits; one Harvia LED strip set is rated to about 60 °C and is meant for low positions such as under benches and behind backrests. The product's own instructions govern where it can go.

Hot air rises, so the top of a sauna is far hotter than the floor. Harvia's Cilindro heater manual, for example, requires electrical equipment more than 1000 mm above the sauna floor to be approved for 125 °C (marked T125). Fittings that high must carry that kind of rating, and many decorative products do not.

No. The air above the heater is the hottest in the room and is where the temperature sensor usually sits. Harvia's manuals ask that lights not be placed over the heater, and every fitting must also respect the heater's published safety distances.

The fibres carry only light. The light source, the part with the electronics, sits away from the hot zone, either outside the room or low inside it where the product's rating allows. Harvia's sauna fibre sets, for example, have a power source rated IPX4 for ambient temperatures up to 80 °C. Fibre is often used for starry ceilings or small points of light in hot positions.

Usually, with a separate control unit. Harvia's Xenio and Fenix controls, for example, have a lighting output, so the lights come on with the sauna and can be switched from the panel or app. The light load must suit the control's rated output, and a licensed electrician connects it.

Fittings sealed for a saturated room. Harvia's steam room guidance asks that every lighting type's suitability for humid conditions be confirmed and cites IP65, and it uses fibre-optic lights on the ceiling and bench fronts. Some other manufacturers cite IP67. The luminaire maker and the licensed electrician confirm the product and position.

Most sauna lighting is warm white. Harvia's sauna fibre lights and LED strip sets, for example, are published at about 3000 K. Warm light flatters timber and keeps the room calm. Coloured or tunable lighting is available in some systems but is a matter of taste.

Yes. Glass loses far more heat than an insulated timber wall, so manufacturers add notional volume when sizing the heater. Harvia adds about 1.2 m³ for every square metre of uninsulated surface, including glass. Its own example is a 10 m³ room with a glass door, which needs about the same heater output as a 12 m³ room. Other makers use different allowances, and the manual for the selected heater governs.

So that anyone inside can leave by simply pushing the door, even if they feel faint or fall against it. Harvia's instructions say the sauna door must open outward, and other heater manufacturers say the same.

No. Heater manufacturers say a sauna door must not have a lock or latch that could stop it opening. Harvia allows magnetic catches, friction catches and spring- or gravity-loaded closers instead. Its installation instructions even ask for the roller latch to be loosened so a new door cannot lock itself on first closing.

Purpose-made sauna doors use toughened (tempered) safety glass. Harvia's sauna glass doors, for example, use 8 mm tempered safety glass in timber or aluminium frames. In Australia, glass in buildings is governed by AS 1288:2021, and the glazier and certifier confirm the glass for each project.

Yes, but its size depends on the ventilation design, and Harvia's own documents differ. Its 2015 planning guide allows up to 25 mm under the door, while its 2022 glass door installation instructions recommend 100–200 mm under a sauna door for ventilation. If the sauna is designed to exhaust into a washroom under the door, Harvia instead requires a gap of at least 100 mm and mechanical exhaust in the washroom. The gap is part of the ventilation design, so it is set with the heater's documentation.

Timber stays comfortable to hold in a hot room, while metal conducts heat and can become uncomfortable. Harvia offers a long vertical timber handle in aspen or alder as an alternative to a chrome knob on its sauna glass doors.

Yes, and it is common in contemporary saunas, but it has to be engineered for. The heater must be sized for the glass, the glazing must be airtight and fixed to suit the structure, the outside surface can get hot, and ventilation may need to change if the heater stands in front of the glass. Harvia notes that a professional must assess whether a glass wall can be installed at the demolition stage of a renovation.

Not quite. Steam rooms face constant moisture rather than dry heat. Harvia specifies 8 mm tempered glass, 8 mm double-layer laminated and tempered glass, or polycarbonate for steam room doors, with a gap of about 15 mm under the door. Some manufacturers specify double-glazed windows. See our steam room design guide.

A traditional sauna uses a heater to warm a mass of stones and the air in the room, and water thrown on the stones gives löyly, a brief rise in humidity. An infrared sauna uses emitters that warm people and surfaces directly while the air stays much cooler. There are no stones, so there is no löyly, and water must never reach the emitters.

In our usage, a hybrid sauna is one room with a traditional stone heater and infrared emitters. The word is also used elsewhere for heaters with a built-in evaporator, and for infrared-only cabins with mixed emitter types, so it is worth checking what a supplier means before comparing quotes.

It depends on the selected equipment and its instructions. Harvia describes the heater and the infrared panels in its hybrid saunas as controlled separately and makes no statement about running both together. At least one integrated control is designed to allow it, but only under conditions such as an infrared cut-off above a set room temperature and emitters with their own overheat protection. Some suppliers advise against running both at once. It should never be assumed.

No. A combi heater is a stone heater with a built-in water evaporator that adds humidity for softer, lower-temperature sessions. A hybrid sauna, as we use the term, adds infrared emitters to a room with a stone heater. They solve different things, and a room could in principle have neither, either or both.

No. A hybrid is a traditional sauna with a stone heater, löyly and the usual sauna ventilation, to which infrared emitters have been added. An infrared sauna has emitters only, no stones and no löyly.

Manufacturers commonly quote about an hour for a correctly sized traditional heater in a well-insulated room. Infrared emitters reach full output almost immediately, and one infrared-cabin maker suggests a pre-heat of about 10 to 15 minutes. A cold room, an outdoor setting or a lot of glass lengthens warm-up for either type.

Sometimes. It needs emitters rated for the temperature of a hot sauna, benches and backrests that suit the emitter positions, access for wiring behind the lining, a control arrangement that suits both the heater and the emitters, and enough electrical capacity. In practice it often means rebuilding the backrests or part of the wall lining.

We do not make health claims for either type, and we are not aware of good comparative evidence that one is healthier than the other. Choose on the experience you enjoy. If you have a medical condition, are pregnant or take medication, talk to your doctor before using any sauna.

Only slightly. The air temperature rises by a few degrees, but the moisture in the air rises sharply for a short time. The burst of heat you feel comes mainly from water vapour condensing on your skin, which is cooler than the air, and releasing its heat as it does. It fades within minutes as the room settles.

It depends on where you measure. Controls read the air near the ceiling, and the bench is cooler than that. Heater manufacturers commonly suggest setting around 65 to 80 °C, and the Finnish Sauna Society's long-standing reference range is 80 to 100 °C at head height. Most people find their own comfortable setting within those ranges.

Harvia gives about an hour for a correctly sized heater in a properly insulated room; another maker quotes 45 to 90 minutes for its heaters. Glass, tiled or masonry surfaces, a cold outdoor room or a heater that is too small all lengthen it.

A little at a time. Harvia's manuals set a maximum of 0.2 litres per throw, and say never to throw water while someone is close to the heater. Another manufacturer limits throws by room size instead, to about 100 ml per cubic metre, with around ten minutes between throws so the stones can reheat. The two are different methods, so follow your own heater's manual.

Because hot air layers under the ceiling, and some rooms make the difference worse. Common reasons are a foot bench that sits below the level of the heater stones, a ceiling that is too high, fresh air entering low across the floor, or a heater design that sends heat straight up. A Finnish test found a closed-body heater left about 36 °C between ceiling and foot level, far more than a tall open-mesh design. The cure depends on the room, so it is worth having the benches, ventilation and heater looked at together.

Because hot air rises and collects under the ceiling. A modest ceiling keeps that heat close to the people on the upper bench instead of heating empty space above their heads. Heater manufacturers and Finnish practice put the upper bench about 1,000 to 1,200 mm below the ceiling.

Heaters are sized by room volume. Each model is rated for a minimum and maximum volume in cubic metres, and glass, masonry, tile and other uninsulated surfaces add to the volume you size for. Harvia, for example, adds about 1.2 cubic metres for every square metre of such surface. Other manufacturers use different allowances, so the final choice follows the selected heater's own sizing table.

No. An oversized heater warms the air before the stones are fully hot, so water thrown on them can run through without making good steam, and it may fall outside the model's rated volume. An undersized heater heats slowly and its stones cool quickly when water is thrown. The right heater sits comfortably within its rated range for the corrected room volume.

Manufacturers commonly quote about an hour for a correctly sized conventional heater in a well-insulated room. High stone-mass heaters can take longer, while heat-storage heaters kept on standby can be ready in minutes. Glass, a cold starting temperature and poorly stacked stones all lengthen heat-up.

It depends on the model and its output. Some smaller residential heaters are offered in single-phase versions, while larger residential and commercial heaters commonly need three-phase. Some models are published in more than one electrical configuration. In Queensland, the distributors' connection manual may also limit how much some single-phase equipment can draw, so a single-phase version is not automatically suitable for every house. A licensed electrician confirms what the site can supply and how the heater is connected.

Some heaters have a thermostat and timer built in. Others are made to work only with a separate control unit and a sensor in the room, which allows digital temperature setting, pre-set timers, lighting and fan control, and placing the controls outside the hot room. The heater model determines which approach applies.

Manufacturers state which user group each heater is designed for. Harvia, for example, lists each heater for households, professionals or both. Commercial heaters are built for long daily running, with heavier construction, a larger stone mass, elements that can be reached for service and, on some heavy-duty models, stones kept apart from the elements. Commercial controls allow longer on-times under supervision rules set by the manufacturer, and guarantee terms for commercial use are much shorter than for a family home.

Not with Harvia heaters. Harvia's manuals allow only one electric heater in a sauna room, so a large room gets one larger heater rated for its volume. Some other manufacturers allow several heaters in one room with extra safety limiters. The manual for the selected heater governs.

A sauna heater with a built-in water evaporator, so the room can also run cooler and more humid. Harvia's Virta Combi, for example, has a 5-litre evaporator that is filled while the heater is cold, used at about 40 °C for gentle humidity, and drained after every use once it has cooled. A combi heater is not the same as a hybrid sauna, which pairs a stone heater with infrared emitters.

No. Heater manufacturers prohibit chlorinated pool or spa water and seawater on the stones because they damage the heater. Use clean household water, and add only scents made for saunas, diluted at the dose on the label.

Some control systems allow app or remote start. Harvia, for example, permits it only where the heater or sauna door has a cover sensor or door switch, and the room must be checked before a remote or timed start. Whether it is available depends on the heater and control combination.

Harvia's manuals ask for the stones to be rearranged at least once a year, more often if the sauna is used frequently, with fragments removed and broken or crumbling stones replaced at the same time. Harvia's newest Spirit manual and its help centre go further and suggest replacing the stones about once a year in a family sauna used around twice a week. Other manufacturers publish shorter intervals for commercial use, such as every second month, every two or three months, or every 500 operating hours. The manual for your heater governs.

No. Collected stones are not a type or size the heater was designed and tested with, can crack and crumble in the heat, and Harvia warns they may contain unwanted substances. Use only the stones your heater's manual specifies.

No. Stones should be placed loosely so hot air can rise through them, with a denser outer layer only where the manual asks for one. Never wedge stones between or against the elements; the stones should support each other. Tightly packed stones trap heat around the elements, which slows the sauna and shortens element life.

Every session heats them to several hundred degrees and every ladle of water cools their surface suddenly. Over months that repeated thermal shock opens up cracks until stones split or crumble. Harvia notes that occasional bangs from a heater are usually stones cracking in the heat.

Harvia's Spirit product pages recommend rounded olivine diabase stones, 5–10 cm, in four 15 kg boxes of its rounded stones (about 60 kg). Earlier Spirit manuals allow rounded stones only, while the newest manual also lists split-face stones but recommends rounded ones over the air channel. Follow the manual supplied with your heater.

Not for most heaters. Harvia's help centre says ceramic "stones" and soft soapstone do not store enough heat and can lead to overheating and broken elements, and several manufacturers prohibit them outright. A few heaters are designed for specific ceramic stones; use them only where the heater's manual says so.

Only on the top layer, and only as the heater manufacturer allows. Harvia limits its decorative stones to one 10 kg box per heater, placed loosely on top and not touching the elements, and says they may crumble or discolour. They never replace the heater's normal stones.

Not beyond what the heater is designed for. The stone quantity and size are set by the heater's manual. Piling extra stones on top restricts the airflow through the heater, which Harvia warns against, and can make the heater run hotter without improving the steam.

No. Most sauna heaters are permanently wired in by a licensed electrician rather than plugged into a socket, and Harvia allows remote, app or timed starts only through its own controls with a door switch or heater cover sensor fitted, or with a heater certified to the covering test the control’s manual names. Switching a heater from an add-on relay or smart plug would bypass those safety devices. Monitoring the room temperature with a separate sensor is a different thing and does not control the heater. If you want app control, ask about a control that is compatible with your heater.

It depends on the heater. Some heaters have a thermostat and timer built in. Others, including Harvia's E models and most commercial heaters, are made to work only with a separate control unit and a temperature sensor in the room. A separate unit adds digital temperature setting, longer pre-set timers, lighting and fan outputs and, on some systems, app control.

Only with the right safety device. Harvia permits remote, app or pre-timed starts only where a heater cover sensor above the heater or a door switch is fitted, or where the heater has passed the covering test the control's manual names. The room and the heater must be checked before every remote start, and the control blocks a timed or remote restart for six hours after the heater last switched off.

Sometimes. It depends on whether your heater and control are compatible with an app-ready panel. In Harvia's range, for example, the Xenio WiFi remote kit is listed as compatible with XE model heaters and the 2020 versions of the Xenio CX170 and CX110C control units, and it comes with a door sensor. Harvia describes its Fenix WiFi touchscreen as a plug-and-play update for Xenio control panels. A heater with built-in switches, or an older or different control, may need a new control system or may not be suitable at all, and the manufacturer's compatibility list for the exact model governs. Remote start still needs the safety device the manual requires, such as a door switch or heater cover sensor (unless the heater is certified to the covering test the control's manual names), and a licensed electrician connects it. Send us the make and model of your heater and control and we can look at the options.

Because the control limits heating time. It stops a heater being left on for hours in an empty room. Harvia's controls for family saunas allow up to six hours, and longer limits are reserved for commercial and public saunas, under supervision rules set by the manufacturer.

Not yourself. A tripped overheat protector means something made the room or heater dangerously hot, such as crumbled or tightly packed stones, a heater left on unused for a long time, or a displaced or damaged sensor. Harvia says only a person authorised for electrical work may reset it, after the cause has been found. Contact us or your service provider.

The control's manual sets the permitted positions. Outside the hot room, near the door, is the simplest choice. Some manufacturers allow a panel inside the room only low on the wall, away from the heater and where the air stays below a stated temperature. The power unit that switches the heater normally goes outside the room in a dry, accessible place.

Some controls have an extra output for infrared emitters, while Harvia describes the heater and panels in a hybrid sauna as controlled separately. Whether both may run at the same time is set by the manufacturers of the exact heater, emitters and control. We never promise simultaneous use.

It depends on the site, the building the heater sits in and how the flue leaves it. Whether approval is needed, and which building requirements and standards apply to a sauna stove and its flue, is decided for each project by the building certifier and the local council. Raise the wood heater and flue with them before anything is ordered.

It depends on the model. Harvia's Legend 150 manual, for example, gives 200 mm to combustible material at the sides, 250 mm behind, 500 mm in front and 1000 mm to the ceiling, while its M3 manual gives 250 mm, 300 mm, 300 mm and 1200 mm. Protective sheaths can reduce some distances on the models they are made for. The manual for the selected heater governs.

No. Harvia's manuals rule out painted or impregnated (treated) wood, chipboard, plastics, coal, briquettes, pellets, waste, garden waste and liquid fuels. The Queensland Government's wood-heater guidance likewise says to burn only dry, seasoned, untreated wood. Treated and painted timber can release toxic fumes.

Each heater is rated for a range of room volumes. Harvia's M3 and Legend 150, for example, are both rated for 6–13 m³. Uninsulated surfaces such as glass, tile or masonry add to the effective volume, and Harvia adds 1.2 m³ for every square metre of uninsulated wall or ceiling. The selected model's manual sets the range and the correction.

BSC Wellness is the Australian agent for Dundalk LeisureCraft. Where a LeisureCraft sauna is wood-compatible, its heating is a Harvia wood-burning heater, and we confirm the heater for the model and the site. Flue, approval and installation requirements are confirmed separately for each site.

Harvia's troubleshooting lists leaks in the flue connection, a cold flue, low pressure from an extractor fan or other device in the building, a full ash box, blocked smoke channels and a connection pipe pushed too far into the flue. Stop using the heater and have the heater and flue checked before the next fire.

Some can. Harvia offers a pipe-mounted water heater for certain wood-burning models, and some stoves have a built-in water container. Whether one suits your heater, and what extra protection the hot pipe needs, is set by the heater's manual.

No. Heater manufacturers publish different layouts, and some are close to opposite. Harvia's international manuals bring fresh air in near the heater and take it out low, far from the heater. Another maker designs for natural draught only, with the inlet under the heater and the outlet high on the far wall. Some heaters, such as heat-storage models or heaters standing in the middle of the room, need their own air-supply arrangement. The vent positions for any room come from the installation manual of the heater selected for it.

Harvia's international manuals ask for the air to change about six times an hour, and several other makers give the same figure. One European maker of large heaters gives at least five, and long-standing Finnish guidance gives a range of about three to six. The figure that applies is the one in the selected heater's installation manual. In commercial rooms the mechanical engineer also designs for the number of bathers.

It depends on the heater and the building. Harvia gives layouts for both natural (gravity) and mechanical exhaust, and makes a fan mandatory when the sauna exhausts through an adjoining washroom. Another manufacturer designs for natural draught only and advises against a fan on the sauna exhaust. The heater's manual and the building's ventilation design decide it, and any fan is wired by a licensed electrician.

Some difference between floor and ceiling is normal in every sauna, because hot air rises. A large difference often points to the airflow, for example cool supply air entering low and away from the heater and pooling across the floor. Supply air that is warmed by the heater as soon as it enters, with the exhaust low and far away, tends to mix the room and even out the temperature.

The working inlet and exhaust are generally left open while the heater runs; some manufacturers say the inlet must never be closable. Where Harvia shows a separate drying vent, it stays closed while heating and bathing and is opened afterwards. Follow the instructions for your heater.

Harvia allows the sauna to exhaust into an adjoining washroom under the door, but only with a gap of at least 100 mm under the sauna door and a mechanical exhaust in the washroom. Bathroom exhaust is also governed by the National Construction Code, so the arrangement has to be coordinated with the building's ventilation design.

If incoming air blows across the sensor, the control reads the room as cooler than it is. The heater then runs longer, the benches overheat, or the room never seems to reach its setting. Harvia's diagrams keep the sensor at least 1000 mm from a supply vent that blows in all directions, or 500 mm from one that directs air away from the sensor.

No. Shower waterproofing is designed to stop liquid water, and many shower membranes let water vapour pass through. A steam room holds saturated air for the whole session, so it needs a full enclosure, a continuous low-permeance vapour-control system across walls, ceiling and floor, a sloped ceiling, insulation and sealed penetrations. Adding a generator to an ordinary shower risks hidden moisture damage behind the tiles.

Manufacturers generally describe steam rooms as running at about 40–50 °C with humidity at or near 100 %. Harvia's steam controls, for example, set the room between 30 and 55 °C. That is far cooler than a sauna, but the saturated air makes it feel very warm. Always follow the operating limits of the selected generator.

Steam condenses on every surface. On a flat ceiling the water gathers and drips onto bathers. A sloped, curved or vaulted ceiling lets it run to the walls and down to the floor drain instead. Harvia asks for a curved ceiling or a slope of at least 15°; other sources use a shallower figure. There is no single correct slope, so the design follows the selected generator and waterproofing system.

Yes. Steam condenses on every surface until that surface warms up, so heavy, dense finishes such as stone or tile on masonry take longer to heat and need more generator output. Glass keeps losing heat outward. A light, insulated shell such as acrylic, or tile on insulated board, warms faster. Each manufacturer sizes for this differently, so the generator is chosen from the selected brand's own tables.

It needs care. Harvia advises avoiding porous natural stone in steam rooms, and some board and membrane manufacturers do not recommend it over their systems. Stone can stain or deteriorate under constant vapour, and it needs a considerably larger generator. If stone matters to the design, confirm it in writing with the waterproofing system manufacturer and the stone supplier first.

It depends on the generator system. Harvia's guidance uses an insulated door with a gap of about 15 mm underneath for supply air, together with planned ventilation. Some other manufacturers specify a gasketed, sealed door and no ventilation during use. Each approach is sized differently, so the door must match the selected generator's instructions.

Outside the steam room, in a dry, ventilated, accessible space close by, usually a plant cupboard or room with a floor drain. Harvia limits the air temperature around its generators to 30 °C, which Queensland roof spaces can exceed. Our guide to steam generator location and service access covers the detail.

Harvia makes mechanical supply and exhaust ventilation mandatory for public steam rooms and recommends it for homes. Some other manufacturers design for a sealed room during use and drying afterwards. The generator is sized differently for each, so the ventilation approach must match the selected system. Either way, the room should be dried after use.

For household use it is considered good quality, but by steam-generator standards it is moderately hard. Seqwater's figures for the year to August 2026 give the Brisbane supply zone an average total hardness of 118 mg/L as calcium carbonate, which is above the point at which some generator manufacturers ask for a water softener. The Gold Coast and Sunshine Coast averaged much softer water. Hardness varies from place to place, so the water at the site should be tested.

It depends on the water at the property and on the generator. Harvia recommends a softener where the water is hard and publishes a water-quality table its guarantee depends on. One European manufacturer requires a softener above 4 °dH, roughly 71 mg/L. In softer areas a home steam room may need only regular descaling. Compare a test of the water at the property with the selected generator's manual.

Often, but it depends on the generator. Several manufacturers require a softener for public or commercial use whatever the local hardness, while Harvia ties its requirement to its water table and the water at the site. Either way, commercial generators need interval flushing and scheduled professional servicing. Harvia asks for a thorough service at least twice a year for community and institutional use.

Yes. Softening slows scale but does not stop it. Manufacturers say plainly that a softener does not replace regular descaling and maintenance, and some scale remains even with automatic flushing.

No. Methods are brand-specific. Harvia's manuals describe descaling with a citric acid solution. One North American manufacturer forbids chemical descalers on its commercial generators altogether. Use only the method in your generator's manual.

No. Most generators drain and flush themselves after a session and need power to do it. Harvia's HGX manual says not to disconnect the power while the tank empties after switch-off. Cutting the power stops the flush and is a known cause of scale build-up. Use the control panel to switch off, and leave the supply on.

No. Length times width times height is the starting point, but the walls, ceiling, floor and benches absorb heat and condense steam, and some materials do so far more than others. Glass, outside walls, a tall ceiling, ventilation and a long steam pipe also increase the output needed. Manufacturers publish different volume ranges for different constructions for this reason.

Dense materials such as stone, concrete and tile on masonry take in a great deal of heat before their surfaces warm up. Until they do, steam condenses on them instead of heating the air. In Harvia's published tables, the same generator suits a considerably smaller room with tiled stone walls than with light walls.

No. Each manufacturer uses its own wall categories, corrections and tables, and the results differ. For a Harvia generator, Harvia's own tables govern. Never apply one maker's factor to another maker's generator.

Makers differ. One North American manufacturer argues that the finish correction exists mainly because home steam rooms start from cold, and that a room running continuously needs less of it. Harvia's commercial HGP220XW table still gives a smaller room volume for tiled stone walls than for light walls. Follow the selected generator's documentation.

No. Harvia publishes a minimum as well as a maximum room volume for each model, so a room can be too small for a generator. A larger unit also needs a larger electrical supply. The aim is the model whose published range suits the room as built.

Yes. Air removed from the room takes heat and moisture with it, so manufacturers that publish separate figures allow a smaller room volume for the same generator when the room is ventilated. Harvia makes mechanical ventilation mandatory in public steam rooms, so commercial rooms are normally sized from the ventilated figures.

In Queensland, usually not. Harvia limits the air temperature around its steam generators to 30 °C, and roof spaces in South East Queensland can run well above that in warm weather. A roof space is also hard to reach for servicing and is a poor place for a hot discharge drain. A ventilated cupboard or plant room at the level of the steam room is the safer plan.

For Harvia's HGX, HGD and HGP generators, the manuals give a maximum of 10 metres of well-insulated steam pipe and recommend keeping the generator as close to the room as possible. Harvia's steam room guide prefers under 6 metres, at the same level as the room. Other manufacturers publish different limits, so the selected generator's manual governs.

Only if the space meets the manufacturer's conditions. Harvia requires sufficient ventilation around the generator if it is in a cabinet or similar closed space, and the 30 °C ambient limit still applies. Some manufacturers rule out vanities and small cupboards altogether because heat builds up. The space also needs a floor drain and room to service the unit.

Not with a Harvia steam generator. Harvia's manuals say the control panel cannot be installed in the steam room; it goes in a dry area such as the bathroom, dressing room or living area. The temperature sensor is the part that goes in the room.

To a floor drain in the plant space, never into the steam room. Harvia notes the discharge water is about 70 °C, and its pipes must fall away from the generator. The drainage is designed and installed by a licensed plumber.

Steam generators need regular attention: emptying the sediment cup, cleaning the water-level sensor, descaling and, in commercial use, a thorough service at least twice a year under Harvia's manuals. A generator hidden where a technician can't reach it turns routine servicing into a building problem.

It treats the cold water on its way into a Harvia steam generator or combi heater so less scale forms inside it. Harvia's manual describes a cartridge with a particle pre-filter and activated carbon, then ion exchangers that remove lime, then a final carbon and particle stage. The cartridges reduce the lime content and carbonate hardness of the water. Harvia's product page says the HWF removes nearly all calcium, magnesium and other minerals.

Harvia's manual gives two criteria. The cartridge must be replaced when it reaches the capacity in litres that Harvia's table gives for the water's carbonate hardness and the filter's bypass setting, and Harvia recommends replacing it every 12 months even if capacity is left. A water meter on the filter outlet tracks the litres used. In hard water or busy commercial use the litres run out sooner, so the change is driven by use, not only by the calendar.

Harvia sells it as a water filter system, but its manual says the cartridges are used to soften cold tap water, using ion exchangers to reduce lime and carbonate hardness. It is a disposable cartridge, not a salt-regenerated softener. Harvia sells a separate automatic softener, the HWS 1500, for commercial use, listed in EU, UK and US versions.

Not automatically. It depends on the water at the property, how much the generator is used and what the generator's manufacturer requires. Harvia recommends treatment where the tap water is hard and makes its guarantee depend on its water table, and some manufacturers require softening for all commercial use. In soft water a home steam room may manage with the generator's own flushing and regular descaling. Test the water at the site and compare it with the selected generator's manual.

There is no universal answer. It depends on the manufacturer and model, the water hardness and treatment, the hours the generator runs and whether it is in a home or a commercial setting. Harvia's HGX, HGD and HGP generators show a service light 200 operating hours after the last service, and Harvia asks for a thorough service at least twice a year when a generator is in community or institutional use. Follow the manual for your exact model.

Yes. Automatic draining and rinsing throw away the most mineral-rich water and loose sediment, which slows scale build-up, but they do not stop it. Harvia's manuals still call for descaling, sediment cup emptying, level sensor cleaning and, in community or institutional use, a thorough service at least twice a year.

No. Switch off at the control panel and leave the supply on. The automatic drain runs after switch-off and needs power to finish. Harvia's HGX manual says not to unplug the power while the tank empties. Cutting the power leaves concentrated, mineral-rich water sitting in a hot tank, which is how scale forms.

On Harvia's HGX, HGD and HGP generators, descaling is one of the few maintenance jobs the manual allows non-professional users to do, using a citric acid solution and the rinse steps the manual sets out. Other manufacturers use different methods, and one forbids chemical descalers on its commercial range. Use only the method in your generator's manual, and leave it for the service visit if you aren't comfortable.

On Harvia's HGX, HGD and HGP generators the indicator light starts blinking when 200 operating hours have passed since the previous service. It is a reminder that maintenance is due, not a fault. The service counter is reset after the service.

Switch it off at the control panel, keep clear of hot water and steam, and call a licensed or authorised service person. Leaks and repeated tripping are not owner jobs, and safety devices must never be bypassed.

There is no single product for every steam room, because tile, grout, mosaic, terrazzo, natural stone and glass react differently. A pH-neutral cleaner made for tile or stone is the safe default for routine cleaning. Acidic limescale removers suit only surfaces that are acid-resistant, and that includes the grout. Check the instructions from your tile, grout, stone and sealer suppliers and your installer before using anything stronger.

Only where every surface it touches is acid-resistant. Vinegar is an acid. The Natural Stone Institute warns that vinegar, lemon and other acids can dull or etch marble, limestone and travertine, the National Terrazzo & Mosaic Association lists vinegar among the products not to use on terrazzo, and one Australian grout maker says its cement-based grouts corrode in contact with acid. Glazed tile and glass may tolerate it, but the grout between them may not.

Be careful. One Australian grout maker allows well-diluted bleach on its grouts but warns that strong bleach can affect grout colour, and terrazzo associations advise against bleach on terrazzo. Never mix bleach with ammonia or acidic cleaners, and do not use Harvia's acidic heater cleanser together with chlorinated products. Follow the grout and cleaner makers' instructions and rinse thoroughly.

No manufacturer sets one interval for every steam room. A quick rinse and squeegee after each session, with the room dried as designed, does most of the work. How often a deeper clean is needed depends on how much the room is used, water hardness, the finishes and whether it is a home or commercial room. Commercial rooms need a written cleaning schedule.

It depends on the grout. Grout makers say epoxy grouts never need sealing, while cement-based grout is porous, so sealing is recommended or optional to improve stain resistance and make cleaning easier. A sealer used in a steam room must suit constant moisture and heat, so check with the installer and the sealer maker, and reseal when they advise.

Only when the generator is off and the outlet has cooled, because steam from the outlet is scalding. Harvia's commercial generator manual says the steam nozzles can be cleaned with a mild soap solution. Do not take the outlet apart, use abrasives, or block or cover it.

Generally not. The National Terrazzo & Mosaic Association recommends neutral pH cleaners and advises against degreasers, bleach, vinegar, ammonia, household chemicals and cleaners containing harmful acids or alkalis. Terrazzo is usually sealed, so follow the sealer maker's and installer's instructions as well.

Only if the heater, controller and supervision arrangements are set up for it. Manufacturers that reference the international sauna heater safety standard set different maximum on-times for different uses, and the longest settings are reserved for public saunas with staff supervising. Harvia's current Fenix control, for example, offers commercial limits of 12, 18 or 24 hours, and Harvia says a public sauna heater run without a timer, or for longer than the factory timer allows, must be constantly supervised. Record the controller settings at commissioning.

It is not advisable. Manufacturers publish guarantee terms by user group, and cover for commercial or institutional use is usually much shorter than for a family home. Harvia's terms for several heaters and controls, for example, are two years for families and three months for institutions or commercial facilities. Some residential steam generators are not warranted for commercial use at all. Choose equipment the manufacturer rates for your operating hours and supervision model, and confirm the terms in writing.

Not with Harvia heaters. Harvia's heater manuals, including those for its commercial Virta Pro and Club Pro ranges, allow only one electric heater in a sauna room, so a large room gets one correctly sized commercial heater. Some other manufacturers allow several heaters in one room under conditions set in their manuals. The manual for the selected heater governs.

There is no reliable published figure. Recovery depends on heater or generator output relative to the room, the stone mass, the amount of glass and other uninsulated surfaces, the ventilation rate and how long the door stays open. Sizing to the manufacturer's allowances, a self-closing door and sensible door management all help.

Queensland Health's water-quality guideline for public aquatic facilities addresses pools and spa pools rather than saunas or steam rooms specifically. Operators should seek advice from their local council, environmental health officer and work health and safety adviser, and follow the equipment and timber manufacturers' instructions.

Far more often than at home. Harvia advises rearranging the stones at least once a year, or more often if the sauna is in frequent use, and a commercial sauna is in very frequent use. Other manufacturers publish commercial intervals of every two to three months, or set them by operating hours. Follow the interval in the manual for your heater and record each check.

Harvia requires steam generators in community and institutional use to be serviced thoroughly by a professional at least twice a year, and its generators show a service reminder after 200 operating hours. Between visits, staff carry out the simple tasks the manual allows, such as emptying the sediment cup and descaling. Other manufacturers set their own schedules, so follow the manual for your generator.

Some control ranges offer gateways to building protocols such as KNX or Modbus, and some offer app control or remote monitoring. Availability depends on the product, so confirm the protocol with your services engineer before the equipment is selected. Remote operation still requires the safety devices the manufacturer specifies.

Published limits differ between jurisdictions and sources. Set operating temperatures within the equipment manufacturer's range, state them on your safe-use signage, keep control of the settings with staff and record temperatures as part of your daily checks.

Possibly, but check before you buy. Manufacturers state which user groups each product is made for and set guarantee terms by how it is used. Harvia's terms, for example, give two years for families, one year for building residents and three months for commercial facilities, and they do not describe holiday rentals as a separate class. Ask the supplier to confirm in writing which terms apply to your use before the heater is ordered.

Only if the control and heater are set up for it. Harvia permits remote or timed starts only where a door switch or heater cover sensor is fitted, or where the heater has passed the covering test the control's manual names, and the room must be checked before every remote start. With a door switch, opening the door cancels the armed start, so in practice the remote start is set up by whoever last checked the room.

That is set in the control at installation and depends on the use class. Harvia's Xenio control, for example, allows 1 to 6 hours for a family sauna and 1 to 12 hours for a public sauna in an apartment building. Longer settings belong to supervised commercial saunas. Choose the setting with the installer to suit how guests will use the room.

Keep it short and practical. Never cover the heater or dry towels in the room, use small amounts of clean water on the stones only, children stay supervised and away from the heater, how to switch off, and who to call if something seems wrong. Base the wording on the heater and control manuals, and avoid any claims about health.

It depends on the building, the work and the by-laws. A sauna can involve new electrical circuits, ventilation, plumbing or waterproofing that affect common property or shared services. Ask the body corporate early, and confirm approvals with your building certifier and your insurer before work starts.

Because there is no single correct interval. How often stones need attention or a steam generator needs descaling depends on the model, the water hardness and treatment, the operating hours, the use class and the condition found at each check. Harvia, for example, ties stone care to frequency of use and steam generator service to operating hours and use class. Set each interval from the manual for your equipment and your own records, then adjust it as the log shows what your room actually needs.

Only those the manual for each product allows. For Harvia steam generators, users may empty the sediment cup once the generator has cooled, clean the water-level sensor and descale as the manual describes. Cleaning, visual checks and recording are staff tasks. Opening electrical equipment, resetting overheat protection, bypassing any safety device or dismantling a generator are not.

Yes. Harvia's guarantees for heaters, controls and steam generators depend on installation, use and maintenance following the manuals, and for steam generators on meeting the water-quality requirements. A dated log is how you show that. It also shows the operating hours that service intervals depend on, and lets a technician see patterns, which shortens fault-finding and downtime.

Use your browser's print command on this page and choose landscape orientation for the wide tables. The checklist and the blank log print with the rest of the guide; print only the pages you need, or copy the log columns into your own spreadsheet or log book.

The light is a reminder that service is due, not a fault to clear. On Harvia generators it comes on after 200 operating hours since the last service. Record it in the log and arrange the service the manual calls for; resetting the reminder without doing the work removes the prompt but leaves the scale.

Ideally at concept or schematic design, and certainly before framing. Equipment selection drives clear height, wall build-up, structural loads, power and water supply, drain positions, ventilation and plant space. Changing equipment after framing is the usual cause of rework.

It depends on the build-up and the products chosen. In a sauna, the lining, battens and air gap sit inside the vapour-control layer on every wall and the ceiling, and benches and the heater guard take further space. In a steam room, the board or mortar bed, membrane and tiles do the same. Treat any figure as indicative until the system is confirmed, and set out from finished internal dimensions.

Most heater manufacturers specify taped aluminium foil with the shiny side facing the room and a ventilated gap behind the lining, but at least one major manufacturer's building guide does not recommend foil or plastic in the wall. Because sources differ, the vapour-control approach should be confirmed for each project against the selected heater's documentation and the wall's position in the building.

Framing is chosen to meet the whole building's termite management, which the builder and certifier decide under the NCC and AS 3660.1. WoodSolutions lists H2 or H2F treated pine for framing in termite areas. None of the heater manufacturers we reviewed says whether treated framing may sit behind a sauna lining, so ask the timber or treatment supplier about heat exposure. The lining, benches and backrests themselves stay untreated.

Not on its own. Shower membranes are designed to stop liquid water, and many are vapour-permeable. A steam room needs a continuous, low-permeance vapour-control layer across walls, ceiling and floor, sealed at every penetration. Use one manufacturer's system with a written statement that it suits steam-room use.

Not at the time of writing. Specifiers usually combine adjacent worksections — waterproofing of wet areas, ceramic tiling, thermal insulation and pliable membranes, light timber framing, glazing and joinery — with a proprietary section from the sauna or steam specialist.

Usually not without care. Manufacturers set maximum ambient temperatures around the generator — one widely used range limits it to 30 °C — and Queensland roof spaces often run far hotter. Generators also need a floor drain, service access and a short steam pipe run, so a ventilated plant cupboard or room close to the steam room is the safer allowance.

At design development, once a heater or steam generator has been nominated. The supply, the number of circuits, isolation, controller and contactor positions and sensor cable routes all follow from the manufacturer's data, and they need to be confirmed before the switchboard and supply are finalised and before walls are lined.

That is for the licensed electrician to determine under AS/NZS 3000 and the heater manufacturer's instructions. Give the electrician the installation manual for the selected heater early, so circuit protection is designed with the full manufacturer data in hand.

It depends on the manufacturer. Maximum steam pipe lengths in the documents we have reviewed range from about 5 m to about 18 m, and some manufacturers prefer much shorter runs than their maximum. The selected generator's manual sets the limit, so the plant location should be confirmed against it at design stage.

Generally not. Sauna lighting has to suit the temperature at its position, and the top of a sauna is far hotter than a normal room. Manufacturers typically keep LED strips and drivers low in the room and require high-temperature ratings for anything mounted high. The luminaire manufacturer's rating and the licensed electrician decide what goes where.

Responsibility is set by the contract. In Queensland, waterproofing is a separate QBCC licence class, and most building work valued over $3,300 needs a QBCC-licensed contractor, so confirm the licences needed with the QBCC. Good practice is to install one documented steam-room system, with the system and hold points agreed between the specialist, waterproofer and builder, and the waterproofing pathway confirmed by the building certifier.

Sources differ. Some heater manufacturers and design sources recommend a floor drain, especially in commercial rooms where floors are cleaned often. Another manufacturer prefers draining to a waste outside the room, because a rarely used trap can dry out and let odours in. Either way, drainage needs to be planned with the floor set-down, falls and waterproofing at design stage.

Oiling is optional, and the interval depends on the manufacturer. Harvia recommends paraffin oil on benches one to three times a year, depending on how often the sauna is used. Another heater maker suggests a sauna-suitable oil if needed after washing or sanding. Use only a product made for saunas, follow its instructions, and let it dry fully before using the sauna.

No. Manufacturers advise against bleach, chlorine and harsh household cleaners on sauna timber, and against pressure washing the interior or using abrasive pads. Use warm water with a mild detergent suitable for saunas, a soft brush or cloth, and dry the room afterwards.

Harvia asks for the stones to be rearranged at least once a year, more often with frequent use, with fragments removed and crumbled or broken stones replaced. Other manufacturers set their own intervals, such as yearly or every 500 operating hours, whichever comes first. Commercial rooms need much more frequent attention. Follow your heater's manual.

Manufacturers agree the room should be dried and ventilated after each session but differ on the details. Harvia suggests running the heater for about 10 minutes with the vent open and the door ajar; another maker suggests 30 minutes with the heater on, then opening the vents and door. Follow your heater manufacturer's instructions.

No. Harvia prohibits chlorinated water and seawater on its heaters, and other makers rule out pool and spa water too. Use clean household water only, and if you are on tank or bore water, check it against the water-quality limits in your heater's manual.

Yes. Cedar staves swell and shrink with the weather, so LeisureCraft asks owners to check the stainless steel bands within the first month and periodically after that, and its manuals give about every six months. Bands should be secure but not over-tightened. Band checks are owner maintenance, not a warranty item.

Owners can keep the heater clean, keep the stones in order and keep the area around it clear. Electrical work, element replacement and resetting the overheat protector inside the heater's connection box are for qualified people. Harvia states that all service operations must be carried out by professional maintenance personnel.

Harvia's heater manuals set a maximum ladle volume of 0.2 litres, and Harvia's own plastic ladle holds exactly that. More water than the stones can flash to steam runs through the heater, cools the stones and can splash boiling water. Some other manufacturers set their own limits, so the manual for your heater governs.

Because they measure different places. The control's sensor sits high in the room near the heater, where the air is hottest, and it controls and protects the heater. A thermometer mounted at bench height shows the air you are actually sitting in, which is cooler. A difference of several degrees or more is normal and does not mean either is faulty.

Only products made for sauna use, and only as their maker directs. Harvia's sauna scents are mixed into the water poured on the stones, or used in parts designed for scent, such as scent cups. Never pour an essence or oil neat onto hot stones; other manufacturers warn that undiluted essences, alcohol and herbs can catch fire.

Not every heater, but many manuals call for one or specify the clearances a guard must keep, and commercial heater manuals commonly include a safety railing. Where a guard is used, it must keep to the clearances in the heater's manual. The manual for the selected heater, and the room's design, decide.

It puts water, or water mixed with sauna scent, onto the heater's stones at the press of a button or at set intervals, so bathers don't need to lean over the heater with a ladle. Harvia's Autodose is aimed at professional and spa saunas. It needs a water supply and an electrical connection, and its compatibility with the heater and room should be confirmed before it is specified.

Manufacturers differ. Harvia's North American manuals advise against wooden duckboards as flooring for hygiene reasons and prefer a tiled or similar cleanable floor. If a removable grate or mat is used, it should lift out so it and the floor beneath can be cleaned and dried.

Yes. Harvia's manuals say the heater and the new stones give off a smell the first time they are heated, and the Spirit manual says to allow for this the first few times. Ventilate the room well until the smell clears. A smell that keeps coming back after the first few heats, or any smoke or burning smell beyond that, should be reported.

No. The safer approach is to run the first heat with nobody inside and the room ventilated, so the smell from residues burning off the heater and stones can clear. Some manufacturers say so explicitly and suggest repeating the heat if the smell persists.

Harvia says a correctly sized heater in a properly insulated room takes about an hour to reach bathing temperature, with the stones reaching temperature at about the same time. Heat-storage heaters behave differently and have their own instructions.

Harvia's Cilindro manual suggests about 65–75 °C as a suitable room temperature, and other heater makers suggest ranges up to about 80 °C; your heater's manual sets the limits. Starting at the lower end is sensible while you get to know the room. Remember the control's sensor sits high up near the heater, so the benches are cooler than the setting.

A little at a time. Harvia's manuals set a maximum ladle volume of 0.2 litres. Throw it onto the stones, never when someone is near the heater, and let the stones recover before the next ladle. Use clean household water only, never pool, spa or sea water.

Usually because the stones aren't hot enough yet. Give the heater the full heat-up time. If it keeps happening once the room is hot, Harvia points to a heater output too high for the room, ventilation, or stones that are packed, settled or the wrong type, which is worth having checked.

Only briefly, to help dry the room, and only as your heater's instructions describe. Harvia says to switch the heater off after bathing and notes that leaving it on for a short while can help dry the timber; its care instructions suggest about 10 minutes with the vent open and the door ajar. Always check the heater has actually stopped heating.

Usually not. Harvia's manuals say the cause must be found before the reset button is pressed, and that only a person authorised to carry out electrical installations may reset it unless the product's manual says otherwise. On some models the button is inside the heater's connection box. Switch the heater off and call a service person.

On Harvia's Xenio and Fenix sauna controls, E1 and E2 point to the temperature sensor's measuring circuit (broken or short-circuited) and E3 to the overheat protector's measuring circuit. The remedies involve sensor wiring and the overheat reset, which are jobs for a service person. Codes vary between products, so always look the code up in your own control's manual.

Not necessarily. On Harvia's Xenio and Fenix controls these are status messages, not faults. Door means the door switch circuit is open, so close the sauna door. SAFE means the cover sensor (Harvia's "safety switch") above the heater has detected something on it, so remove the object. A message such as rESt means a 6-hour pause before a timed or remote start is active.

On Harvia's HGX, HGD and HGP generators the maintenance light starts blinking 200 operating hours after the previous service. It is a reminder that servicing is due, not a fault. Arrange the service, which includes descaling and cleaning as the manual describes, and the counter is reset afterwards.

Harvia requires the steam pipe to fall towards the steam room with no water pockets, and other manufacturers explain that condensate trapped in a dip can be pushed out as spitting hot water. Scale and a fouled water-level sensor are other causes named by manufacturers. Stay clear of the outlet and arrange a service visit.

Harvia says occasional bangs are usually stones cracking in the heat, and that heater parts expanding as they warm can make noise. On heaters with a mechanical timer, ticking is normal while it runs. If the timer ticks when the heater is switched off, or the noise is new and different, have it checked.

Harvia's guarantees can be voided if the installation, use or maintenance instructions aren't followed, or if non-recommended stones are used, and its steam generator guarantees also depend on water quality and servicing. Stick to the checks the manual allows owners to make, and keep your proof of purchase and installation and a record of servicing.

Harvia's instructions for its full-spectrum radiators are to switch the radiator off, let it cool, then wipe the glass with a damp cloth. Never pour water over a radiator, never immerse it and don't get it too wet. Other emitters have their own instructions, so follow the manual for your model.

Harvia describes its VitaMy and FIR full-spectrum radiators as maintenance-free, so owner care is limited to cleaning and checking. A radiator with cracked glass, a damaged cover or a fault should be inspected by a qualified person; Harvia's Vitae manual says a broken radiator must always be replaced with a new one.

Yes, onto the stones only, in small ladles, as your heater manual allows. Keep water and splashes off the emitters. Harvia's radiator manuals say not to pour water over them and not to install them in a steam bath, and its Vitae manual says they must not be installed above the heater.

Only if the selected heater, emitters and control are designed for it. Harvia controls the heater and panels in its hybrid saunas separately, and its Vitae radiator manual recommends using the radiators in hybrid rooms at temperatures under 70 °C. Never assume simultaneous use; follow the manuals for your equipment.

Walls generally need no treatment. If you treat benches or backrests, use only a sauna-specific product, follow its data sheet, keep it off the emitter glass and covers, and let it dry fully before switching the emitters on. Never use paint, varnish or lacquer inside the room.

Yes. There is no löyly, but people still sweat and the timber still takes up moisture. Leave the room to air with the door ajar after use, keep the vents open as designed, and take towels out.

Less than many people expect. A room for one or two people can be quite compact, because capacity comes from bench length rather than floor area. Allow about 600 mm of bench per seated adult, and a bench of roughly 1.8–2.0 m if someone wants to lie down. Then add space for wall insulation and lining, the heater and its required clearances, and an outward-opening door.

Count bench length, not the label on a brochure. Around 600 mm of bench per adult is a comfortable allowance. Two tiers of benches add seating within the same footprint and put bathers higher in the warmer air.

Harvia gives about an hour for a correctly sized electric heater in a properly insulated room, with the stones reaching temperature at about the same time. Heaters with a large stone mass can take longer. Large areas of glass or tile, a cold starting temperature or an undersized heater all slow things down.

Often, yes. Saunas are regularly integrated into bathrooms and ensuites. It needs careful coordination with the room's waterproofing, the sauna's ventilation and the bathroom's exhaust, and the electrical work, so it is best planned at design stage rather than added later.

Opinions differ. Some manufacturers say a drain is not required in a private sauna but is convenient, while others recommend one in new construction, particularly where floors are washed down. A floor waste is worth serious consideration where the sauna sits within a wet area or will be cleaned with water. Any waste is plumbing work for a licensed plumber.

No. Heater manufacturers are consistent that only clean household water should be used on the stones. Chlorinated pool or spa water and seawater can damage the heater, and at least one manufacturer warns that chlorinated water can release chlorine gas.

It depends on the project. An indoor sauna is often part of a fit-out, but structural, waterproofing and electrical work may still need certification. A freestanding outdoor sauna may need building approval depending on its size, height and location. Your building certifier decides how the work is classified and what approvals apply.

It depends on the size of the sauna, where it sits on the block and the planning and building rules that apply to your property. Some small outbuildings need no building approval and others do, and the building certifier decides how a sauna is classified. Check with your council or a private building certifier before you order, and include any wood-fired heater or flue in that conversation.

The cabin itself does not care where it is used, but the heater, lighting and controls do. Ratings published for North America are not Australian specifications. The heater needs to suit Australian supply, and the electrical work must be designed and installed by a licensed electrician to the heater manufacturer's instructions.

Kits are designed to be assembled from pre-cut parts with ordinary carpentry tools, and the manufacturer recommends at least two people for the job. Electrical connection is a separate matter and must be done by a licensed electrician. Any wood-fired heater and flue also need to be installed to the manufacturer's requirements and whatever your certifier and council require.

No. Untreated cedar weathers to a silver-grey outdoors, which does not stop the sauna working. If you want to keep the natural colour, the manufacturer suggests a UV-inhibiting exterior stain or oil, recoated as it wears. Paint and varnish are not recommended on the exterior, and no stain should be used inside the hot room.

Treat the person rating as a maximum rather than a comfortable number. Retail ratings often assume shoulder-to-shoulder seating. Check the interior bench length on the drawings and allow roughly 600 mm per seated adult, or about 1.8–2.0 m if someone wants to lie down.

A kit suits a freestanding outdoor sauna where one of the standard shapes and sizes fits your space and style. A custom sauna suits rooms built into a house, unusual spaces, specific heaters or finishes, and projects where the sauna needs to match the architecture.

Size is only one of many factors. The timber grade, the amount of glass, the heater or generator, the controls, the finishes, the services available on site, access, and whether the room is for home or commercial use can each change the scope more than a few extra square metres. A quote needs the drawings, the intended use and the site conditions.

A kit's design and manufacture are already done, so there is less design work and the room arrives as a set of parts. The total still depends on the site, including the base, the power supply, access for delivery, assembly and any approvals. Compare the full installed scope, not just the room.

Usually, in more than one way. The glass, framing and door hardware are costs in themselves, and glass loses heat, so manufacturers ask for a larger heater or steam generator when there is more of it. A larger heater or generator can in turn need a larger electrical supply.

It varies by contract, but building work such as framing and structural reinforcement, licensed electrical and plumbing work, tiling, mechanical ventilation and approvals are often carried out or engaged separately. Ask every supplier for a written list of what is included and excluded so quotes can be compared fairly.

Mainly the heater or generator output, how long it runs each time including heat-up, how often it is used, how well the room is insulated and how much glass it has. Steam rooms add water treatment and descaling, and commercial rooms add longer operating hours and scheduled professional servicing.