Steam Construction

Steam Room Construction


The following information is presented as an aid to those installing a steam generator or constructing a steam room. Due to complex construction variables, climate variances and changes in manufacturing specifications, this information represents suggestions only. It is recommended that you consult your architect, material manufacturer and/or specification engineer regarding your particular installation. Please see the disclaimer at the end of this guide.


When planning to install a steam room, the objectives of comfort and relaxation should be kept in mind. A properly designed and constructed room should maintain a temperature range of 115° to 120° Fahrenheit, heat to this temperature in 15 to 20 minutes, and have a comfortable seating arrangement. Space permitting, seating which allows the bather to recline or even lay down greatly enhances the steam bath experience.

Steam Room Design Considerations:

  1. A steam room, unlike a sauna, is a moist environment. Avoid using construction materials which are subject to corrosion or decay.
  2. All inside surfaces of the steam room must be completely sealed and covered with a waterproof finish such as tile. Sheet-rock surfaces are not recommended. However, fiberglass re-enforced cement sheet-rock such as "Dura Rock" or "Wonder Board" may be used if properly sealed against moisture with a commercial waterproof paint. All joints or cracks including shower head, handle escutcheon and steam escutcheon should be sealed with silicone. Acrylic or fiberglass enclosures recommended for steam by the manufacturer also make excellent steam rooms.
  3. Ceiling and seats inside the steam enclosure should be sloped to allow condensation to run off the interior surfaces and prevent dripping on the bather. A ceiling slope of 2 inches per foot should be adequate. In some installations, sloping the ceiling from the center may be required to minimize the ceiling height.
  4. A floor drain should be provided for cleaning and allowing water drainage and a nonskid floor surface should be used for safety.
  5. Ceiling height should be limited to 8 feet. Heights in excess of 8 feet may result in hot or adequate temperatures near the ceiling, but uncomfortably cool floor temperatures.
  6. An area for mounting the steam generator must be selected to provide the following:
    1. Allow access for servicing and providing sufficient space to remove elements should they ever need replacing.
    2. Protect steam generator from freezing, moisture and areas which might exceed 140°F (Do not mount the generator in the steam room or in an outside location).
    3. The all-copper line from the steam generator to the steam room should not exceed 25 feet, should always slope toward the steam generator or steam head, should not form traps or valleys allowing condensation to accumulate, and should be insulated to prevent heat loss and prevent burns from accidental contact.
    4. The steam head should be located in accordance with the generator installation instructions and minimize potential user contact.
    5. When installing the generator, plumbing unions should be used to allow removal of the generator should service be required.
  7. When selecting a construction material for lining the inside of your steam room, make sure to contact the material manufacturer to determine that the material is warranted for the hot, moist conditions of a steam room.
  8. The steam room must be totally enclosed.
  9. Ceiling vents in the steam room are not recommended. If used, they must form a vapor-tight seal and positive closing ducts must be waterproof.
  10. Skylights and exterior windows are not recommended. If used, they must be double pane. Caution must be used to insure that the height and size of a window or skylight in a steam room does not prevent the room from maintaining comfortable temperatures in a reasonable length of time.

Selecting the proper steam generator:

In order to achieve the objective of comfort and relaxation, the selection of the proper steam generator model and size are as critical as design of the steam room itself.

Model selection considerations:

  1. Water Quality: The more impurities or minerals in the water the more flushing and/or filtration is required to reduce build-up in the tank. An automatic flush and water filtration system should be considered where the water quality is poor to reduce manual flush maintenance requirements.
  2. Thermostatic Control: The thermostatic controller or air switch gives the option to regulate the temperature of the room. In installations where the steam generator is used frequently and for greater length of time the cost of a thermostatic control or air switch may be justified to provide a more even temperature in the steam room.
  3. Digital Display: The preferences of the bather may be for simple on/off simplicity or for more advanced feedback, including time of day, set temperature, temperature in the steam room, remaining steam bath duration, and programmability.

Power (KW) selection considerations:

  1. Cubic footage of steam room and surface area.
  2. Steam room surface material mass, Rfactor and thermal conductivity.
  3. Ceiling height relative to height of seating.
  4. Are steam room walls exterior walls subject to large temperature fluctuations?
  5. Actual line voltage and phase available (one phase or three phase, 240 volt or 208 volt, the lower the voltage the lower the steam output).
  6. To avoid rewiring and provide the capability to "size-up" if it turns out a generator of insufficient size is installed, it is strongly recommended that the next larger or even second larger wire size be installed for the generator you select.

DISCLAIMER: This information represents recommendations only. Due to conditions of your installation, these suggestions may not be applicable. AMEREC manufactures steam generators only and therefore can not warrant and should not be relied upon for information given concerning steam room materials or construction techniques.