The sauna’s floor covering can be solid or with a free drain, tiled, or wooden. We have prepared installation instructions for each type.
The atmosphere in the steam room largely depends on the floor covering. We tell you how to correctly make the sauna floors so that you can steam with comfort and pleasure.
What is the best material for a sauna floor: choosing materials
The materials of the floor covering in the sauna should be environmentally friendly, without an unpleasant smell when heated. And most importantly resistant to mold and decay. Usually, two main types are used.
Wood
Wooden floors will help to maintain a pleasant forest aroma in the steam room. The material does not like high humidity, but with the right choice of type and proper care, wooden flooring will last 5-8 years.
Pros
- Natural material.
- Pleasant to the touch surface.
- Heats up quickly.
Cons
- Varieties with high moisture resistance are expensive.
- It needs to be dried regularly.
- Requires frequent replacement.
What boards are suitable for installing finishing floors in a sauna?
- Made from larch – the best quality-price ratio slowly absorbs water, does not rot due to resins and fights bacteria, and smells nice when heated.
- Alder is relatively inexpensive and water resistant.
Pine is a little cheaper but will swell faster even with careful care. Cedar, oak, teak, and abashi are the species from which ships were once made. They are very durable and not afraid of water, but very expensive.
Any wood after installation must be treated with a water-resistant compound. Choose special oils or impregnations marked “for a bathhouse”, or “for interior decoration”. They do not emit harmful substances when heated.
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Concrete
A concrete floor is much more practical than a wooden one and can last up to 50 years. But it is more difficult to do it yourself without experience.
Pros
- Durability.
- Easy to care for.
- Possibility of laying additional finishing coating on top.
Cons
- Complexity of work.
The concrete floor is cold and unpleasant to the touch. It is always covered with something on top the steam room you can use:
- plank flooring – small square “mats” that are easy to remove and dry;
- ceramic tiles or porcelain tiles – if installed correctly, they reliably protect the base from moisture.
In the dressing room and the recreation room, concrete is covered with tiles, wood or decking. There, the humidity and temperature are lower, so the requirements for materials are lower.
Whatever material you choose to lay the floors in the sauna, you first need to prepare the foundation for the stove. A separate base is required for fireboxes heavier than 750 kg. And even light ones are advised to be placed on their own foundation so that uneven loads do not deform the joists and cause the concrete to crack.
When creating a foundation for a stove, immediately think about fire protection for the floor. Between the wood and the firebox, you need to lay a layer of heat-resistant insulation, a brick podium, or a ready-made pedestal from the manufacturer. It is also not recommended to put stoves on tiles without thermal insulation: temperature changes can cause ceramics to crack. Check the conditions with the manufacturer of the sauna stove.
“Estrich” cheapest and fastest way to get a concrete floor
How to lay floors in a sauna: two technologies for installing boards
There are two options for laying wooden floors in a bathhouse:
- with free flow of water from the cracks between the boards into the ground;
- with a drain into a pipe leading to a septic tank or sewer.
Free-draining floors dry faster, but in winter they let in cold from the ground. If the soil underneath is too dense, the groundwater is high, and a swamp of stagnant water will appear in the crawl space, which smells bad.
Solid flooring is warmer, but requires replacement more often: some moisture still stagnates in the boards. It is more difficult to lay since the angle of inclination must be carefully calculated.
The type of boards for the finished floor depends on its design. In any case, they must be carefully planned on all sides. But solid floors are laid from tongue and groove boards with ready-made locks. And spilling, or leaking, – from ordinary.
With free drain
How to lay a sauna floor with free water drainage into the ground? Installation is very simple but requires careful preparation of the base.
- Measure the depth of the crawl space. To create a proper drainage cushion, it should be about 60-70 cm. Deepen it if necessary.
- Calculate the size and number of logs, and draw an approximate diagram of their installation. The logs are laid parallel to the short wall with a step of 0.4-0.8 meters, retreating from it by 0.2-0.3 meters. For a bathhouse, a 100×100 mm beam is enough. But you can’t save on the type of wood. Take a beam made of waterproof wood.
- Form support columns that will prevent the logs from sagging in the center. One column is needed for every meter of timber. The optimal dimensions are 250×250 mm. Each column should have a monolithic base. Concrete is poured into the formwork up to 5 cm high. After hardening, brick supports are placed on the solution. They should reach the upper edge of the strip foundation. The logs are not placed directly on the bricks, but after a layer of waterproofing – coating or roofing felt.
- Fill the space around the posts with a 10-15 cm layer of sand. Level it, but do not compact it. If the soil is sandy and the area is dry, you can skip this step. Lay a 15-25 cm layer of crushed stone. The denser the soil, the thicker the layer of crushed stone you need.
- Treat the joists with antiseptics and dry. Lay them on supports and level them using underlays. For leaking floors, a slope is not needed, the joists should lie in one plane.
- Fix the joists to the supports using anchors, and metal corners on the lower crown of the log house. Leave about 4 cm between the edges of each and the walls to compensate for deformation. Treat the attachment points with a coating waterproofing or sealant.
- Cut the clean board and start laying it across the joists. Step back 1-2 cm from the wall, leaving an equal gap of 2-3 cm between the boards. When laying each next one, check the floor level: it should remain level. Secure the boards at the intersections with the joists with 1-2 nails.
If the soil is clayey and does not absorb water well, you can make a leaky floor, but with a centralized drain into a septic tank or drainage. The stages of creating the underground will differ. We will tell you about the rules for its construction below.
Solid decking
The continuous flooring goes at a slight slope to the wall, which has a drain trap, covered with a decorative grate. The work also begins with the arrangement of the underground.
- The sand and gravel cushion and supports are made according to the same principle as for leaking floors. However the crushed stone should be laid at a slope of 10-15 cm to the point of water drainage. You can check this using a stretched thread or a laser level.
- At the drain point, a pit is dug 70 cm deep and 50 cm wide. Its walls and bottom are covered with a dense layer of clay from 15 cm or concreted over a reinforcing mesh.
- From the pit, you need to lay a drain pipe at an angle to the septic tank or sewer. Lower the drain pipe of the trap into the pit itself. The water that still seeps under the floor will go into the pit and into the sewer.
The logs are laid from the wall opposite the drain. If it is in the center, then they go to it from both sides. Each subsequent beam is lowered by 0.5-1 cm below the level of the previous one. This can be achieved by an additional layer of waterproofing, and cutting the timber in places of contact with the finished floor.
To form the correct slope, lay the joists and finished floor on a level area next to the bathhouse. Mark the places for cutting, cut everything to size, and treat with an antiseptic. Then move and fasten to the support posts. You cannot make holes in the joists. Lay them in such a way that the drain gets into the gap between them and the wall.
Nail small square bars 2-3 cm high to the joists at the bottom on each side. Lay the subfloor on them – plywood or boards, securing them with nails. Put film waterproofing on the underlay, then insulation on top, and then a layer of the same insulation. Expanded clay can be used as insulation. Mineral wool does not like high humidity, and polystyrene foam can release toxic substances when heated.
After the top layer of waterproofing, the finished floor is laid. If you have done everything correctly before, the boards will go at an angle to the drain. If the slope is not enough, you can put small pieces of plywood under them. After that, all that remains is to install the drain.
In the dressing room or other dry rooms
A solid floor is much more convenient and practical here. It is laid without a slope, on perfectly level joists. However, a sand and gravel cushion is always provided in the base for additional protection from the cold and rotting of the boards.
How to make floors in a sauna with your own hands from concrete: step-by-step instructions
If you have chosen concrete floors for your bathhouse, first of all, decide on the drain location and lay a pipe from it to the septic tank. Only after that can you start building the foundation.
- The sand and gravel cushion is made perfectly flat. First, a 20-30 cm layer of crushed stone is laid, then the same layer of sand. They are rammed, leveled, and covered with film waterproofing or roofing felt. Its connections with the crown or foundation are reinforced with coating waterproofing. Film insulation is brought a little onto the walls.
- A heat insulator — expanded clay — is placed on the insulation layer. A second layer of waterproofing is placed on top. A reinforcing mesh with a rod thickness of 5 mm is rolled out on it. Beacons are installed, forming a slope of about 5-10% towards the drain. After this, the solution can be poured. It will dry for at least a week, longer in cold weather.
You can lay tiles or continue the remaining finishing work in the sauna only after the concrete has completely dried.
Rules for the care of flooring and concrete
- Treat dried concrete with a waterproof primer containing antiseptics to protect against mold, even if you are going to lay tiles on top.
- Renew the impregnation of the entire tree annually. Immediately replace the boards on which you notice cracks. Without repair, water will accumulate in them.
- Check the condition of leaking floors once a year. Remove the finished floor and take it out to dry in the sun. Rinse the top layer of rubble with clean water from a hose to wash off the soapy film. Or replace the rubble with fresh rubble. Treat open areas of the joists with protective compounds.
- Do not leave wet towels in the steam room or dressing room. Ventilate the sauna thoroughly after each steam session. You can turn on a dehumidifier in the relaxation room to reduce the humidity level.
