A Finnish sauna runs at 80-100 °C with 10 % humidity. A steam room runs at 45 °C with saturated vapour. They share neither envelope, nor ventilation, nor finish.
Most domestic saunas and hammams fail for the same reason: they are installed as furniture rather than as wet installations. Two years later there are stains on the adjoining bathroom ceiling, cracked timber and blackened joints.
We design these rooms from the envelope inwards: continuous waterproofing, sloped ceilings for condensate, calculated ventilation and timbers that survive thermal cycling without varnish.
Nordic spruce, western red cedar or aspen, unvarnished: varnish degrades under heat and off-gasses. Benches are chosen for thermal conductivity, not looks.
Behind the cladding, so moisture cannot migrate into the partition and condense inside the wall build-up.
Inlet beside the heater, outlet on the opposite wall at height. Without that circuit the air stratifies and bench level never heats properly.
Roughly 1 kW per m³ of volume, adjusted for glazing and cold surfaces. An oversized heater dries and cracks the timber.
Waterproof membrane to floor, walls and ceiling, not only the shower zone: saturated steam reaches every millimetre of the enclosure.
Between 2 % and 5 % so condensate runs to the walls instead of dripping on the user.
Water-repellent microcement, glass mosaic or low-absorption natural stone. No standard plasterboard, no timber.
Generator sized by volume and insulation, with dedicated drainage and accessible servicing for regular descaling.
Steam generator and fan sit away from adjacent bedrooms or on anti-vibration mounts.
The bathroom hosting a hammam needs upgraded extraction, not the standard rate of a conventional bathroom.
In hard water areas, a softener upstream. Limescale is the single biggest cause of generator failure.
Access panels designed in from the start for heater, generator and drain. Without them, every repair means breaking finishes.
Design and site supervision fees. Equipment is quoted with the selected manufacturer.
| Scope | Indicative range |
|---|---|
| Feasibility study (ventilation, drainage, electrics) | 600 – 1,800 € |
| Bespoke sauna design package | 2,500 – 7,000 € |
| Bespoke steam room design package | 3,500 – 9,000 € |
| Turnkey delivery | 9,000 – 45,000 € |
A sauna is simpler to install and maintain and can sit in a dry location. A steam room needs full tanking and descaling but suits people who cannot tolerate dry heat.
From around 1.5 m² for a two-person sauna and 2 m² for a two-person hammam, with 2.10 m minimum clear height.
Yes. A domestic sauna heater usually needs a three-phase or reinforced single-phase circuit with dedicated protection, defined in the electrical design.
Yes, if there is accessible drainage, extraction and enough contracted power. The usual constraint is drainage and ventilation, not floor area.
Sauna: cleaning and an annual check of the elements. Steam room: descaling the generator every three to six months depending on water hardness.
Four to ten weeks from approved design, depending on whether waterproofing and services must be rebuilt.
Tell us where you want it and we will review drainage, ventilation and power before drawing anything.