Whether you are building a new sauna or renovating an old one, you should always invest in careful work and high-quality materials. This increases the durability of your products and ensures a longer service life.

Cover all surrounding surfaces with suitable materials. For example, use hardboard or packing board to protect tile floors.

Pay particular attention to occupational safety and accident prevention. All HVAC and electricity work must be carried out by a professional. Any unprotected electric wires must be protected and their power supply cut off. The locations of any underlying electric wires, water pipes and ventilation ducts should be marked in the structures. This will help to minimize the risk of hitting them with fasteners, such as nails and screws, during the construction phase.

The tools used must be suitable for the purpose. When building a sauna, you should not customize your tools in any way. All tools should be available for purchase at a hardware store or for rent at an equipment rental service.


Framing and setting up the space

After the initial preparations, start the work by inspecting the framework around the sauna. Visually check the framework for any moisture damage and cracks and verify that the insulation is tight. Any damaged parts must be replaced or fixed. Use a spirit level to check that the framework is level. If the framework is significantly slanted, it needs to be straightened. Slight deviations can be corrected later while installing the nailing strip.

Install the necessary ventilation ducts and power supplies between the frame structures. After the framing is complete, install the vapor barrier. The vapor barrier can consist of aluminum paper or aluminum-coated insulant, depending on the method of construction. All seams and lead-ins must be carefully sealed with aluminum foil tape.

Next, install the nailing strip, which will also function as a ventilation strip. It is good to choose strip material that has been planed to the right dimensions, such as 22×48. Check that the strips are level and straighten them with wedges, if necessary. This helps to prevent uneven finished surfaces later on.


Benches, stove & lighting

The bases for attaching the benches and stove must be installed before starting the paneling. Use a suitable material for the base, such as 21 mm softwood plywood. Saw the plywood into 150 mm wide strips and attach them between the nailing strips. When attaching the plywood, make sure that it does not hinder the circulation of air between the vapor barrier and the panel.

The top edge of the plywood used for attaching the benches should be installed at the same height as the top surface of the benches. Typically, the following dimensions are used: top bench h=1,100 and bottom bench h=700, measured from the surface of the finished floor. Please note that the dimensions of your own sauna may be different. Always check the plans for the correct dimensions. The base for attaching the stove should be installed according to the stove manufacturer’s instructions.

Nowadays, saunas are often equipped with fiber optic lighting. The fibers are routed to the desired installation points between the nailing strips. Do not install the fibers under the strips, as they may be damaged during the nailing. Other technical elements, such as the power cord of the stove thermostat, can also be routed between the nailing strips before starting the paneling.



Start preparing for the paneling work by cleaning the floor surfaces. This ensures that there is no debris or litter on the floor, as they could damage the finished floor when trestles are used.

Carefully consider the method of attachment before starting the paneling. Face nailing provides strong attachment, but the nails need to be lined up carefully to achieve a neat result. Blind nailing is an easy way to achieve a neat finish. However, especially when using wide panels, you must always ensure that the attachment is secure enough, as fluctuating moisture levels will cause the wood to move, which may result in panels coming loose.

Start the paneling from the ceiling. Begin by measuring the run of the ceiling (i.e. the width of the area to be paneled). Then, narrow the first panel to the same width as the last panel. This allows you to avoid a result where the first panel is at full width and the last one only a narrow strip.

Cut the first panel on the tongue side so that the groove is left facing you. Leave a gap of at least 5 mm between the fist panel on the ceiling and the nailing strip on the wall. This allows the ceiling panels to expand and contract freely as the moisture level fluctuates. Check the run as the work progresses to ensure that the paneling is even and the panels are not wedging into each other. If the dimensions are not exact, correct them evenly. Do not use the last panel as a wedge.

Start the wall paneling by installing the corner moldings. Cut the moldings to the length of the area to be paneled and attach them lightly to the nailing strips. Start the paneling at the top. Narrow the first panel by cutting off at least the tongue. However, you should check the run of the entire wall and make the first panel even narrower if it looks like the width of the bottom panel might be less than 30 mm. Such narrow strips are difficult to attach, and this may also be visible in the result.

Install the first panel on the wall with the groove facing down. Leave a gap of 3 to 5 mm between the ceiling panel and the wall panel to allow the passage of air. As the work progresses, it is good to keep checking the run and the evenness of the installed panels. If there are any deviations, correct them evenly. Panel all the walls at the same time by proceeding around the room. This helps you avoid a result where the surface patterns of the panels on adjacent walls do not match each other in the corners.



After the paneling is complete, finish the surfaces by attaching your preferred moldings from our comprehensive selection. The stove should be installed according to the plan; either before or after the benches depending on the bench model.

When the sauna is finished and the final cleaning done, it is time to heat up the stove!

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