By The Sauna Company · Published 5 Nov 2026
In the sauna vs steam room choice, a sauna gives you hot, relatively dry air: 75–95°C at the ceiling with 5–15% humidity in a traditional Finnish sauna, plus bursts of steam when you ladle water on the stones. A steam room runs much cooler but is filled with moisture from a steam generator.
For most homes a sauna is simpler to build, because a steam room needs full waterproofing, tiling and drainage. The two also work very well side by side.
Key takeaways
- Different rooms, different build. A sauna is a timber room with dry heat and occasional löyly; a steam room is a fully tiled, waterproofed room filled with generated steam.
- The steam room asks more of your builder. A sauna needs a suitable electrical supply and careful ventilation. A steam room also needs drainage, waterproofing and tiling.
- Prices. Standard Finnish saunas (Aqua Spazio Sana) cost from £9,995 and steam rooms (Aqua Spazio Vapore) cost from £19,995, excluding VAT and builders' work.
- Often both. Most of the steam rooms we build are combined with a sauna.
- Spaces you already have. A shower room can often become a steam room; a spare WC, loft or under-stairs void can often become a sauna.
How do the two rooms feel?
Sauna. Heat comes from a heater loaded with stones. In a traditional Finnish sauna (Aqua Spazio Sana) the air at the ceiling sits at 75–95°C with low humidity of 5–15%. Ladling water on the stones produces a wave of steam, called löyly, that raises the humidity briefly.
Users typically stay up to 30 minutes, often less, then cool off in a shower or plunge. For something gentler, a bio sauna (Aqua Spazio Combi Bio) runs at 50–60°C with 50–60% humidity, sitting between the two experiences.
Steam room. A steam generator mounted outside the room pipes steam in. The air is far more humid and much cooler than a sauna, and moisture condenses on your skin, so the heat feels wet rather than dry. There are no stones to ladle and no timber inside.
For more on how humidity changes the experience, see our post on humidity control in a sauna.
What does each room need from your house?
Sauna
Steam room
Structure
Timber frame, insulation, vapour barrier, timber cladding
Insulated tile backing boards over high-integrity vapour barriers, fully tiled
Water
Not essential (handy for a shower nearby)
Water supply and drainage essential
Power
Dedicated supply sized to the heater (6kW typical for a family sauna)
Supply for the steam generator
Equipment location
Heater inside the room
Generator outside the room, with touch controls
Ventilation
Designed to remove CO2 and even out heat
Steam vented to the outside via an exhaust after use
Ceiling
Flat, ideally about 2.1m high
Shaped so condensation does not drip on bathers
Builder's share
Smaller
Larger: waterproofing, tiling, drainage
The ceiling detail matters more than people expect. In a steam room, condensation forms on every cold surface, so we shape the ceiling and seats to run water away instead of dripping it onto you.
In a sauna, the hidden work is ventilation. A sealed hot room fills with exhaled CO2, and that is what causes the stuffy, light-headed feeling in badly built saunas.
What about finishes and maintenance?
Sauna. Clad in timber: Aspen or Alder for standard builds and Thermo Aspen for premium ones, with benches in low-density timber such as Western Red Cedar. Maintenance is simple. Keep it ventilated and dry after use, and replace the stones annually.
Steam room. Tiled throughout. Finishes include glass mosaic, full-body porcelain, natural stone, slate and marble; a common approach is large-format tiles on walls and floor with mosaic on the seat and ceiling. Lighting is concealed LED.
Because a steam room is a wet room, the quality of the waterproofing and the drainage falls decide how long it lasts.
How do the costs compare?
All prices are fully installed and exclude VAT and builders' preparatory work.
Room
Installed price (ex VAT)
Infrared sauna (Aqua Spazio Radiata)
From £9,995
Standard Finnish sauna (Aqua Spazio Sana)
From £9,995
Premium Finnish sauna (Aqua Spazio Premio)
From £14,995
Steam room (Aqua Spazio Vapore)
From £19,995, tiles up to £50/m² included
Add the builder's costs for a steam room's waterproofing, tiling and drainage, which are usually greater than the preparatory work for a sauna.
What about health?
Most of the published research on regular heat bathing concerns Finnish-style saunas. A 2018 review in Mayo Clinic Proceedings by Laukkanen and colleagues reported that regular sauna bathing is associated with lower risk of cardiovascular disease and several other conditions. It also found a good safety profile, while noting that much of the evidence is observational.
There is far less research on home steam rooms, so we do not make health claims for them. Choose on the experience you enjoy. If you have a heart condition, are pregnant or take medication, speak to your GP before using either.
What did we build in Walton-on-Thames?
In a loft conversion gym in Walton-on-Thames, Surrey, we built both. The sauna has a full glass front (door and side panels), Thermo Aspen cladding, a 2+1 bench layout with a floating upper bench and concealed LED lighting. It is heated by a Harvia Legend 10.5kW with Xenio Wi-Fi control.
The adjacent shower room was refitted as a steam room: old fittings removed, Marmox insulation board fitted, full waterproofing, a new wet-room tray and drainage, and a single bench. Steam comes from a Harvia HGX 4.5kW generator on the same Xenio Wi-Fi system, so one app runs both rooms.
Frequently asked questions
What is the main difference between a sauna and a steam room?
A sauna heats the air with a stove and stones to 75–95°C at low humidity, with steam added by ladling water. A steam room is cooler but filled with moisture from a steam generator. Saunas are timber-lined; steam rooms are fully tiled and waterproofed.
Which is easier to install at home, a sauna or a steam room?
A sauna. It needs a suitable electrical supply and well-designed ventilation but no drainage. A steam room needs waterproofing, tiling, drainage and a generator mounted outside the room.
Can I have a sauna and a steam room together?
Yes, and most of our steam rooms are combined with a sauna. A shower room next to a sauna can often be converted into a steam room, as we did in a Walton-on-Thames loft gym.
How much does a home steam room cost?
Our steam rooms (Aqua Spazio Vapore) cost from £19,995 fully installed, with tiles up to £50 per square metre included. Prices exclude VAT and builders' work such as waterproofing and drainage.
Should I use the sauna or the steam room first?
It comes down to preference, as there is no strong evidence either way. Whichever order you choose, cool down between rounds. Keep sessions to 15–20 minutes and drink water afterwards.
Talk to a sauna designer
Not sure which suits your space? Book a free design consultation, or email photographs and dimensions to 020 8058 0871 for an initial assessment. See our bespoke steam room page for finishes and sizes.
Planning one for your own home? See our bespoke steam rooms page for options and recent projects, or book a free design consultation and we'll talk through your space.
Sources
- PubMed — Laukkanen, Laukkanen and Kunutsor, "Cardiovascular and Other Health Benefits of Sauna Bathing: A Review of the Evidence", Mayo Clinic Proceedings, 2018.
- ScienceDaily — Frequent sauna bathing has many health benefits. Plain-English summary of the same review, including its safety profile.
- Harvia — HGX45 4.5kW steam generator. Wall-mounted generator for household steam rooms of 2–7m³.
- Harvia — Ventilation in the sauna. Recommended air changes and vent positions for electric-heater saunas.
Planning a sauna of your own? See how our sauna installation service works, from free design consultation to handover.