Instructions for building a sauna

The purpose of these instructions is to give basic knowledge about the construction of a sauna and the building process.

In the instructions, the sauna is built into a room made of concrete bricks and ceramic tiles are used for the floor covering. Ventilation is mechanical. The walls are paneled so that heater output can be kept moderately low.

The sauna is equipped with a glass door, which increases the calculated sauna volume by 1.5 cubic meters.

Instructions for building a sauna

Requirements set by the heater

Planning

Read the heater manual and pay attention to the safety distance information. There shall be no inflammable materials within the established safety distances. Neglecting the safety distances causes a risk of fire.

The safety distance requirements for a woodburning stove can be reduced using protective covers. (see the stove’s instructions for installation)

If the heater has a separate temperature sensor, plan the sauna so that it can be installed exactly as described in the installation instructions.

Requirements set by the heater

If you have chosen a Combi heater, the sauna room should have a floor drain. If you have chosen a Combi heater with automatic water intake, there must be a water outlet in the vicinity of the heater.

Also, when planning the electrical wiring, it must be considered that Combi heaters are always controlled via a separate control unit.

Requirements set by the heater

PlanningWiring

Familiarise yourself with the wiring required by lighting, heater, sensor/s, control panel and/or control unit.

Decide if you want to run the cables on or under the paneling.

Wiring

PlanningSauna interior model

Sauna interior model

Exclusive Formula Futura

Scala Solar Ventura

Harvia offers a wide range of possibilities for sauna interior.

We only use high quality materials in our products.

Floor and ventilation

Waterproof the floor according to the building directives. While choosing the floor covering material, consider that particles disintegrating from the sauna stones and impurities in the sauna water may stain and/or damage sensitive floor coverings.

Use floor coverings made of ceramic materials and dark joint grouts. Stone pillar type heaters should be placed on a heat-resistant floor, as hot pieces of stone may fall from the heater.

The floor covering should extend 10-20 cm on the wall. You can fix the covering either straight to the wall or use an underlayment board.

Floor

Ventilation

A. Supply air vent location. If mechanical exhaust ventilation is used, place the supply air vent

above the heater. If gravity exhaust ventilation is used, place the supply air vent below or next

to the heater. The diameter of the supply air pipe must be 50–

100 mm.

Ventilation

B.    Exhaust air vent. Place the exhaust air vent near the floor, as far away from the heater as possible. The diameter of the exhaust air pipe should be twice the diameter of the supply air pipe. If the exhaust air vent is in the washroom, the gap underneath the sauna door must be at least 100 mm. Mechanical exhaust ventilation is mandatory.

Do not place the supply air vent so that the air flow cools the temperature sensor (see the temperature sensor installation instructions in the control unit installation instructions)!

Ventilation

C.    Optional vent for drying.Closed during heating and bathing.

The sauna can also be dried by leaving the door open after bathing.

Frame

Frame

Fix frame battens (50 x 50 mm) to walls. C/c 600 mm or according towidth of insulation material.

Fix ceiling frame battens to wall frame battens. The height of a sauna

is usually 2100-2300 mm.

The minimum height depends on the heater model. The space between

upper bench and ceiling should not exceed 1200 mm.

Insulation

Insulation

Place insulation material between frame battens. Do not leave any gaps in the insulation.

Proper insulation of the ceiling is essential to make the sauna energy efficient. Use double insulation in the ceiling.(minimum 100 mm)

Moisture barrierAluminum paper

Moisture barrier

The purpose of the aluminum paper is to keep moisture

inside the sauna. The moisture barrier must be entirely tight so that moisture cannot enter the

structures.

Fix the aluminum paper using e.g. staples. Place the glossy

side of the paper towards the sauna.

Moisture barrier

Fix the aluminum paper first to the ceiling. Fold the edges on the

walls so that there is plenty of paper for overlapping.

Tape the seams carefully with aluminum tape.

Fix the aluminum paper on the walls and tape the seams. Avoid

placing the seams in corners, because taping is difficult there.

Tape the lower edge of the paper to the upper edge of floor tiling

or waterproofing.

Seal all lead-through areas (air vents etc.) with tape!

Nailing battens, bench supports and heater supports

Nailing battens

Fix the nailing battens (e.g. 22 x 50 mm) to ceiling. Align them with the frame battens.

Fix the nailing battens to walls. The upper ends of the nailing battens should be 20 mm below the ceiling battens. The battens should be installed vertically – otherwise air cannot move upwards behind paneling.

Fix another layer of battens horizontally, if you want to make the paneling vertical.

Bench supports

Check the bench heights from your bench plans.

Reinforce the walls in the areas where bench supports will be fixed. Make the reinforcements from wood, which has the same thickness as the nailing battens.

Fix the reinforcements to the frame battens.

Notice that the bench supports require reinforcement inside the walls. The bench support placing depends on interior model/bench plan.

Heater supports

If a wall-mounted heater is to be installed in the sauna, place an additional support (A) to the wall behind the heater, so that the fastening screws can fix to it. Check the places of the fastening screws in the heater installation instructions.

Have you already thought out the wiring? (See item 1. Planning.)

Paneling

Paneling

Nail the panels to the nailing battens. Start from the ceiling.

Nail a couple of panel rows to a wall at a time, then move to the next wall – by circulating like this, the possible differences in panel widths do not affect the outcome.

Drill holes for wiring and thread the wires through them.

Leave an air gap of a few millimeters between the upper edge of the paneling and the ceiling.

Finishing the interior

Finishing the interior

Fasten the air vents.

Bench supports and sauna lighting

Bench supports and sauna lamp

Fix the bench supports according to your bench plan. The sauna lamp is easy to install at this point.(contact an electrician if necessary)

Benches

Benches

Lift the benches on the bench supports. See the installation instructions

delivered with the benches.

Heater

Heater

Install the heater according to the installation instructions.

Enjoy your sauna!