All about car tuning

Foundation for a sauna stove: rubble concrete, slab, columnar, pile-screw. Foundation for a stove in a bathhouse What size is the foundation for a stove in a bathhouse

The external contour of the bathhouse base is connected using supporting structures for partitions into a single system.

This approach ensures uniform settlement of both the bathhouse and the heating boiler. Laying the foundation for heating equipment occurs in the following order:

  1. the site is leveled and marked along with the rest of the supporting structures of the bathhouse;
  2. a pit is dug for the foundation;
  3. its bottom is leveled with a sand-crushed stone cushion of the required thickness;
  4. going and;
  5. Work is being carried out on waterproofing and reinforcing the furnace foundation.

The cross-section of the supporting structure or the thickness of the base slab is calculated based on the following data:

  1. the weight of the furnace, which in turn depends on the main building material and the size of the equipment;
  2. masses of additional structures of chimneys, tanks for heating water, etc.;
  3. soil composition, depth of freezing and occurrence of soil water.

What is the difference between brick and metal?

A metal stove is much stronger than a brick stove. Installation with a slight distortion or deformation of the base will not cause much damage to a metal stove, whereas for a brick stove such movements of the foundation mean complete failure. Hence the need for a high-strength foundation for a brick kiln. Metal stoves are usually quite lightweight, which makes it possible to do without a separately laid foundation. A foundation for an iron stove in a bathhouse is not required. For them, it is necessary to provide proper fire protection measures - asbestos sheeting, a sheet of roofing iron under a metal stove, protruding beyond the stove by at least 25 cm, and in front of the firebox - at least 40 cm.

A brick kiln, having a much larger mass, cannot tolerate deformations of the base and needs a full-fledged foundation, designed to withstand the high pressure of the kiln and compensate for shrinkage processes. There should be no connection with the common foundation, otherwise the difference in the pressure created on the foundation can lead to destruction.

Depth of laying the foundation for the furnace

When assessing the depth of the furnace foundation, it is necessary to take into account the location relative to the walls of the bathhouse or house, as well as ensure the stability and reliability of the furnace base.
If the foundation under the walls of a house or bathhouse has a shallow depth, then the foundation for the stove is located at the same depth. If the furnace is located near a foundation with a large depth, the base of the furnace is raised and placed on a sand bed. It should be noted that the minimum depth for laying the base for the furnace is 50 cm in both cases.

Foundation for the stove. Example

A stronger and more reliable foundation is made for brick stoves, since the weight of this structure exceeds the weight of a metal one.

  • Dig a hole depending on the location of the furnace foundation. The width and length of the pit should be 20 cm larger than the dimensions of the stove foundation.
  • To save concrete, the finished pit is leveled, half filled with sand, thoroughly compacted and checked for horizontalness.

  • Waterproofing is placed on top of the sand and formwork is made.
  • The top of the pit is poured further with concrete to ground level, which can be reinforced with metal rods for greater reliability. Mortar recipe - one part of cement contains 2.5 parts of sand and four parts of gravel. Next, the foundation surface is checked for horizontalness using a building level.
  • After the concrete has hardened, about 5-6 days, the formwork is dismantled, waterproofing is applied and the foundation for the furnace continues to be built to the level of the finished floor. Part of the base above ground level can be laid out of brick or formwork can be made and filled with concrete mortar to the floor level.
  • The gap between the edge of the pit and the foundation is filled with sand and thoroughly compacted.

Foundation for a furnace on a reinforced concrete slab

This technology is used on soils where the lower layers of soil are weak and the upper layers are more reliable.

Remove the top plant layer of soil, about 20 cm, and level it. Sand, crushed stone or gravel are poured, compacted and a reinforced concrete slab with a thickness of 12 to 15 cm is placed on the resulting base or made on site.

Brick stoves can be installed on a stove with an area of ​​no more than 2.5-3 m2, and light metal stoves with an area of ​​about 1.5 m2. Of course, the larger the area of ​​such a base, the stronger and more reliable the foundation will be.

You can make the stove yourself. To do this, after the stage of laying gravel, it is necessary to install formwork corresponding to the dimensions of the slab. After this, you need to pour concrete to a height of 5-7 cm, correctly lay the reinforcement or reinforcing mesh and pour it to the desired height. Before the solution has set, it needs to be leveled.

After the solution has hardened, it is necessary to apply waterproofing and continue building the foundation for the furnace to floor level. This can be done with brick, rubble or with concrete using formwork.

After a week, coat the upper part of the resulting base with hot tar and cover it with roofing felt.

When installing the stove, it is necessary that its center of gravity coincides with the middle of the stove. When making such a base, about 1-2 m 3 of concrete is saved.

Foundation for a stove on a columnar base

For heavy stone stoves, a columnar foundation of four pillars located at the corners of a reinforced concrete slab or a welded frame made of metal profiles is suitable.

To erect pillars, you need to use a regular hand drill to make holes to the depth of soil freezing.

Then we take asbestos pipes, install them in the pits and fill them with concrete. The width of the asbestos pipe is taken based on the bearing capacity of the soil and the weight of the furnace. How to do this for a house is written in the article Calculation of the foundation. Using the same scheme, calculations are made for the furnace.

Then we install the finished slab or make formwork and fill the slab on site. The height of the pillars depends on the height at which the slab will be installed.

You can also install a frame welded from steel profiles on the poles, which will serve as the foundation for the furnace.

If you choose the exact option foundation for the furnace and do all the work correctly, the structure will last for many years.

Base for a metal sauna heater

With a sauna stove weighing up to 750 kg, you can do without constructing an individual supporting structure - just install a protective floor covering. However, if the floor is wooden, its strength characteristics should be sufficient. It is advisable to check the condition of the joists under the flooring and, if necessary, carry out spot repairs of the area.

A layer of clay mortar is applied to a durable wooden flooring, on top of which a sheet of asbestos is laid in such a format that its edges protrude 25-30 cm beyond the contour of the stove. Excess clay is removed by rolling a paint roller over the asbestos, after which the mortar is given a week to harden and dry. A sheet of galvanized roofing iron of an even profile with a thickness of 0.8-1.0 mm of the appropriate format is laid on top of the asbestos.

Protective materials for sauna stoves – asbestos and galvanized sheet steel

To avoid future injuries, the corners of the iron sheet are given an oval shape and pressed to the flooring with self-tapping screws. The protective platform for the heater is ready.

Options for arranging a protective platform for a sauna heater

For a metal stove, sometimes an individual load-bearing base is still installed, and there is a reason for this - wooden flooring and logs in a bathhouse age faster and lose strength.

The sequence and technology of constructing a foundation for an iron stove in a domestic bathhouse:

  • construction of a pit with a depth of 0.5 m and dimensions in plan that are 10 cm larger than the dimensions of the heater;
  • bottom planning with backfilling of crushed stone with a layer of at least 30 cm and compaction;
  • installation of concrete preparation on top of crushed stone from liquid cement-sand mortar 5 cm thick;
  • after the solution has dried, perform waterproofing with 2-3 layers of roofing material coated with bitumen mastic;
  • formwork installation;
  • production and laying of a reinforcing mesh frame with a cell of 8-12 cm from steel or plastic reinforcement of variable profile with diameters of 8-10 mm (the finished frame should be located in the lower part of the volume of poured concrete - at a distance of 5 cm from the waterproofed base);
  • laying a 20 cm layer of concrete prepared in a ratio of 2:5:8 (cement, sand, small crushed stone);
  • when the concrete reaches 70% strength (in a week), lay brickwork on top of it to the floor level.

Construction of an individual load-bearing platform for a metal furnace

Important! The entire volume of the foundation for a small metal stove in a bathhouse can be made of brick laid on mortar. .

What to consider when planning the foundation for a sauna stove

Let's consider the case when the weight of the stove exceeds 700 kg; the material is brick. What parameters should be used to select? In general, the choice is made for the entire building at once. The terrain of the site is taken into account - whether planning is needed, how difficult or costly it will be.

Dependence on soil type

  • For difficult terrain, slopes or folds best to use screw piles, which eliminate expensive and not always possible excavation work. In addition, they can be screwed in manually without involving complex construction equipment.
  • For dense rocky soils you can get by with shallow tape foundation. In this case, its purpose is to level the site and establish a plane; the bearing capacity of the soil does not require complex measures.
  • Soils with high groundwater levels require pile type of foundations. Digging a pit in such conditions is tantamount to the formation of a small lake on the site, so screw or driven piles are used, immersed in the soil to the level of dense layers.
  • At large depths of soil freezing done strip foundation buried below the freezing point. The depth of the pit in such cases can be more than 2 meters, which is too much for the base of the furnace. The issue is solved by the formation of a sand cushion, tightly compacted and leveled. The thickness of the cushion is such as to bring the bottom mark of the furnace base to the required height, where the next layer is laid - a butcher block or reinforced concrete slab.
  • Areas with high seasonal elevation changes - soil heaving- require or pile a foundation resting on dense layers of soil and raising the entire building above ground level, or arrangement of a continuous monolithic slab, a massive, durable reinforced concrete base. Such a slab moves along with the ground surface, preventing deformation of the building fixed on it. A solid slab foundation is reliable and durable, but requires a significant investment of money and labor, since it is usually built for the entire bathhouse. A separate stove for the stove will not work in difficult and wet soil conditions; its area is insufficient.

Foundation in a bathhouse under a stove, examples of step-by-step work

It is impossible to imagine a Russian bathhouse without a stove. Today, like hundreds of years ago, the furnace must be placed on a pre-prepared foundation, for which the floors are dismantled, a pit is dug and concrete is poured. It is best to start this process at the construction stage, but sometimes the stove is chosen at the last moment, which is why the floor has to be “unraveled.” The task of the foundation is, firstly, to distribute the load from the main structure. Secondly, ensure an adequate level of fire safety. About how to properly make a foundation in a bathhouse for a stove, which one to choose and what is needed for this - in our article.

  1. When building a foundation for furnaces, it is important to consider the weight of the structure. If its weight does not exceed 750 kg and its construction is supposed to be carried out on the first level, then a reinforced concrete base will be sufficient. If the mass of the furnace exceeds the specified indicator, this is the basis for the construction of a separate foundation.
  2. For a stove that is relatively light in weight, it is recommended to choose a columnar foundation. In such a foundation, sufficiently recessed pillars perform the task of piles, and a reinforced concrete slab placed on the ground acts as a support. This option for constructing a foundation structure has gained a reputation as the most reliable structure.
  3. The construction of a foundation for a brick kiln requires special attention. In this case, it is important to prevent even minimal deformation changes in the foundation structure. Otherwise, there is a high probability of cracks occurring in the brickwork, which will subsequently lead to fragmentary or complete destruction of the stove structure.
  4. The stove foundation should only take the load from it. You should not connect the stove foundation to the foundation of the house. A gap of 5 cm should be made between the two bases. This gap should be filled with sand in two layers. Or pave it with waterproofing material.
  5. To correctly determine the size of the future foundation for the furnace, you need to proceed from the structure of the soil and the mass of the furnace structure. When determining the depth of the foundation, you should take into account the water level of the soil, strength and heaving, freezing depth and the level of the foundation of the house.

Before starting construction, the density of the soil must also be taken into account. This point is especially relevant when constructing heavy furnace structures. The most suitable are clayey and sandy soils, as they are sufficiently dense and do not contain excess moisture. If the soil has a loose, heterogeneous structure, it must be compacted before starting work.

Foundation for the stove photo:

Installation of a pile foundation with a slab

One of the types of foundation for a furnace is a pile structure, which is characterized by good reliability and ease of installation.

Foundation on stilts

  1. We make markings on the ground according to the dimensions of the future oven and measure 10 cm in each direction - this will be the size of the foundation.

    2. We remove 20 cm of the plant layer of soil using a bayonet shovel.

    Vegetable soil layer removed

  2. We put pegs and pull the rope.

    3. In each part of the peg we drill holes with a diameter of 20 cm to a depth of 50 cm.

    Pile foundation for the furnace

  3. We make formwork from wooden boards, fastening them together with nails, and set them according to the size of these holes. The formwork is a wooden box without a bottom.
  4. We make waterproofing using polyethylene, which we staple around the perimeter to the walls of the formwork.
  5. Pour sand onto the bottom, compact it well and fill it with gravel to a depth of 15 cm. Fill with water.

    6. We knit the reinforcing bars using 0.8 mm wire and twist them well.

    Knitting reinforcement mesh

    We install a reinforced frame.

    Foundation reinforcement

    We roll up dense sleeves of roofing felt and insert such piles into the pits. Asbestos pipes can be used as piles.

    Ruberoid sleeves

  6. We fill the finished piles and inserted into the hole with concrete mixture.
  7. We take a technological break for 2 weeks.
  8. Now you can fill the entire foundation with concrete mixture.
  9. Cover with polyethylene and let the foundation harden for at least 2-3 weeks.

How to make a foundation for a stove

When making a foundation for a Russian brick oven, you must adhere to the requirements for the foundations of any other structures. Of course, this type of foundation has its own characteristics that you need to know about.

Preparing for work

If you decide to make a foundation for a stove for a wooden house with your own hands, then, first of all, you need to decide what dimensions will be at the design.

When designing, keep in mind that on each side it should be 50 millimeters more than the size of the stove. For example, if you plan to stove size 1/0.7 meter, then the foundation should be 1.1/0.7 meters.

Once you have decided on the dimensions of the structure, you can choose the location of the furnace. Also consider where the chimney will be located; an exception is made only for barbecue stoves. For all other stove options, this is a very important point, because an ill-conceived chimney can rest against the supporting structure on the roof. To correct such a deficiency, you need to spend a lot of time and effort, so it is better to avoid troubles and make accurate calculations immediately.

If the foundation is made for a Russian stove, then it is not necessary for it to come into contact with the foundation of the house. Such structures have different pressures, and upon contact they can be deformed, which will lead to troubles with both bases.

Making a foundation pit

The foundation pit is an important component of the foundation, without it cannot be avoided. It happens that builders remove only the top layer of soil, thereby saving material and time, but this should not be done recommended. The pit should be made below the freezing level of the ground. These characteristics have individual parameters for each region.

You can make a shallow foundation, but then you must use piles. If the soil is sandy and dry, then it will be enough to make a pit half a meter deep. And for heaving soil, it is necessary to dig a pit at least a meter deep. When the foundation has been marked, they begin to dig the pit, while the width and length must be made with allowance for the formwork.

The formwork itself made with boards 2 centimeters thick, they are knocked together into shields and then fixed in the pit with spacers. A ten-centimeter layer of crushed stone is poured onto the bottom of the pit, leveled and compacted.

We do waterproofing and filling

Making the solution:

  • 1 part cement;
  • 3 parts clean sand;
  • 5 parts of crushed stone without impurities.

First you need to mix all the components in a convenient container. When you get a homogeneous mass, you can start adding water little by little. The mixture should be constantly stirred, you need to add water until it works consistency of thick sour cream, only then the solution will be ready. The finished solution can be safely poured into the formwork. It is recommended to do the pouring in one day, otherwise the foundation will end up consisting of several layers, which may crack during use.

Foundation on stilts

For a shallow foundation it is necessary use piles:

  1. To begin, remove the vegetable matter. layer 25 centimeters.
  2. Then you need to use a drill to make holes a meter deep 20 centimeters in diameter.
  3. In the bottom of the holes made, crushed stone is filled and compacted.
  4. It is necessary to insert into the made wells roofing felt rolled into a sleeve.
  5. Further holes are filled with concrete mortar.

You can do it a little differently if you have asbestos or polyethylene pipes the required diameter and length. Then pipes are simply inserted into the holes, and after 10 days the foundation is being poured.

Today, screw piles have become popular instead of concrete ones, but to install them you need to use the services of specialists. This can only be done with skills and good practice. Watch the video how they work specialists with screw piles.

If you decide to make a stove, you should definitely consider foundation design. Even if you really want to save money on construction, it’s better not to do this, otherwise, that’s all the building may collapse. Only by making a high-quality foundation with your own hands, you will be able to use it for many years, and step-by-step instructions will help you with this instructions and video lessons.

Kinds

Modern construction uses a wide variety of materials to Russian stove and foundation. It can be made not only at home, but also in a bathhouse; what could be better than a Russian stove in a Russian bathhouse? Most often done these types of foundations:

  1. monolithic;
  2. pile;
  3. tape;
  4. screw;
  5. under a stone stove;
  6. under an iron stove.

For low-rise and wooden houses they often do strip foundation for the stove.

If the stove is made of iron, then the last option is most suitable, in which there is no foundation as such. Thanks to the design of the iron stove, a high-quality and durable floor covering is sufficient for its foundation.

Often done slabfoundation, especially for brick kilns. The movement of the soil has no effect on the reinforced monolithic slab, but if the structure is very large, then it will not cope with it. Groundwater also affects destructive to her. This stove is not suitable for installations in baths. The cost of such a foundation is low, but its reliability is not the best. There are many videos on the Internet that will help you easily decide the right type of foundation.

Foundation for an iron furnace

Despite the fact that iron sauna stoves are usually light in weight, even for the lightest thin-walled model it is advisable to have a separate foundation. The thing is that even a slight misalignment, sometimes invisible to the eye, leads to accelerated wear. And only the presence of a solid foundation guarantees its absence, and therefore long-term operation of the stove.

Making a foundation for an iron stove is not difficult. Necessary:

  1. Dig a pit of a suitable size. The size of the foundation should be 10-15 cm larger than the dimensions of the stove (more is possible, less is not possible). If the metal furnace is built with a brick screen, then the indentation is calculated from the outer edge of the screen. The depth of the foundation and pit depends on the type of soil. On non-heaving soils, 50-60 cm is sufficient.

    2. Crushed stone is poured into the bottom and compacted thoroughly. The compacted size of this layer must be at least 30 cm.

    Foundation for an iron furnace

  2. Compacted crushed stone is poured with liquid cement mortar. The approximate ratio of materials for its manufacture is as follows: take 4 parts of sand for one part of cement, the amount of water depends on the state of the solution - it should be of medium thickness.
  3. After the layer has dried (in a day or two), a waterproofing layer is laid. This can be roofing felt in two layers or one of the new bitumen waterproofing materials (roll or coating).
  4. The formwork is set according to the selected foundation dimensions.

    5. A layer of concrete is poured. For one part of cement you need to take 2.5 parts of sand, 4 parts of fine gravel or expanded clay (with expanded clay you will get a more thermally insulated base). First, cement and sand are mixed dry until an even color is obtained. Then gravel or expanded clay is poured in and everything is mixed again. When all parts are evenly distributed, dilute with water. Water usually goes a little less in volume than cement. We carefully level the laid out solution, checking its horizontalness using a building level.

    The foundation for the stove can be covered with bricks: it looks more attractive this way

  5. Instead of a concrete layer, you can use bricks. They are placed on a cement-sand mortar.

The formwork can be removed after three days, and the concrete gains its design strength in three to four weeks. For normal ripening, it must be regularly moistened with water: sprinkle generously 2-4 times a day, depending on the temperature. There should be no puddles, but the solution should get wet well. If it's too hot outside, cover the base with plastic wrap to prevent moisture from evaporating quickly.

There is a moisturizing option that does not require frequent spraying: cover it with burlap or some other fabric, add a good layer of sawdust, and wet it. This is enough for a day.

A concrete base is cheaper and stronger, but requires more physical effort, even if you have a concrete mixer. The disadvantages of concrete include the difficulty of dismantling it.

How to line the foundation for a metal stove

If the upper part of the base is cast from concrete, then outwardly it has an unattractive appearance. You can line the foundation with bricks from the outside, but this is only if conditions permit: the brick is still of decent size. For other cases, cladding with thick ceramic tiles (thick ones) is suitable. Porcelain tiles are likely to crack at high temperatures. Perhaps a natural finishing stone would be suitable.

When tiling, place washers made of thick soft metal (copper or aluminum) under the legs of the stove. Sharp, hard legs often scratch the front surface of the tile, causing it to crack. The washers will be insurance against scratches.

Heat Resistant Tile Adhesive

The tiles are laid on a special heat-resistant glue (there are such). The grout is also selected appropriately - resistant to high temperatures. You can do without grouting: carefully open the seams with glue. If you do everything carefully, the appearance will be normal. The grout only looks good at first. Then, when ash and soot are added, you will be tortured to scrub it off.

Concrete foundation

To build a foundation for the furnace you will need:

  • Cement.

If your soil contains a large amount of sulfates and the groundwater level is quite high, we recommend that you use SSPC grade sulfate-resistant cement. The difference between SSPC cement and conventional PC is the ability of concrete made from this brand of cement to withstand the destructive effects of sulfates dissolved in groundwater.

  • Coarse sand without inclusions. The ideal option would be to use mountain sand, but sea and river sand are also suitable. We have already discussed methods for cleaning sand from impurities on the pages of our Internet resource.
  • Formwork material.
  • Crushed stone.
  • Ruberoid or dense polyethylene.

Tools:

  • Solution trough
  • Shovels: bayonet, shovel
  • Building level
  • Hammer, nails, hacksaw for formwork construction
  • Construction stapler

Do I need to go deeper?

You can begin to build the foundation for the furnace. Many may wonder whether it is necessary to go deep into the ground when laying a foundation for a stove with their own hands. Our answer is definitely. Sometimes there is an option in which the foundation is arranged with shallow depth. Only the top plant layer is removed and after installing the formwork the foundation is poured. This is completely the wrong way. The foundation slab, arranged in this way, will be constantly under stress, especially in winter. The motivation for economical consumption of building materials when constructing such a foundation is not justified. The penetration must be carried out to a depth below freezing level in your region. You can use a shallow foundation for a bathhouse under a stove, but with the obligatory installation of piles under the main foundation slab.

Pit construction - main parameters

Digging a pit

For dry, sandy soils it happens 500 – 600 mm is enough. But on heaving soils this depth should not be less than 1000 mm. We repeat - this is the correct foundation design.

Proper laying of the foundation

According to the markings of the swarm pit. The size of the pit must allow the installation of formwork. But if the soil on your site is dense enough and the edges do not crumble, you can do without it. In any case, it all depends on the specific location and soil. When the formwork is installed, the bottom of the pit is filled with layer of crushed stone 100 mm thick. Crushed stone must be leveled. After this, it is necessary to compact the crushed stone using a manual tamper.

Waterproofing and filling

To waterproof the foundation, a layer of roofing material is attached to the inside of the formwork using a construction stapler. You can start filling

It is important to know that the upper level of the foundation should be 60 - 70 mm lower than the main floor of the building. Prepare the solution according to the following proportions:

  • Cement 1 part
  • Sand 3 parts
  • Crushed stone 5 parts

Sand and gravel must be clean. Additional inclusions reduce the adhesive properties of the mortar mixture. It would be ideal if the sand and crushed stone are washed with water.

  • First prepares dry mixture of cement, sand and crushed stone. Can be used.
  • After shoveling and obtaining a homogeneous mass, water is gradually added until a solution of consistency is formed thick sour cream. The solution can be poured.

Try to complete the filling in one day. Otherwise, several layers will form in the foundation, which can lead to cracking.

Construction of the foundation

Under a metal stove You don’t have to build a separate foundation and limit yourself to fire safety shutoffs. However, if the weight approaches the limit value (700 kg), and it consists of the weight of water in a fully filled boiler plus the weight of stones plus the own weight of the stove- it is better to equip a separate foundation for a metal furnace. To do this you need:

  1. Dig a pit (to a freezing depth, but not less than 50 cm), fill it with crushed stone and compact it thoroughly.
  2. A concrete layer is poured on top, which must completely harden. The composition of the solution is cement with sand 1:4.
  3. Double layer of waterproofing (roofing felt or similar sheet material),
  4. Filling the main slab with a solution of cement, sand, fine gravel. While the solution has not hardened, the horizontal line is checked and adjusted if necessary.

Foundation for a brick oven requires a more thorough approach and is made as durable as possible.

  1. A pit is being dug. Most often, this is done simultaneously with a common foundation pit for the entire building.
  2. A layer of sand is added to remove the bottom of the pit. Sand is poured in layers of 15 cm, each layer is spilled with water to compact it. Subsequent layers of sand are added only after the water has subsided. This technology makes sand compaction easier and provides a dense layer. After this, a rubble layer is laid - broken brick, concrete, thickness - 20 cm. Again a layer of sand, spilled with water - and so on until a dense cushion is formed that does not settle when compacted.
  3. A layer of crushed stone 10 cm thick is laid.
  4. Formwork for the main foundation slab is erected on top.
  5. A reinforcement frame, welded or knitted, is installed inside the formwork.
  6. Concrete is poured to a height that does not reach the floor level by 5-15 cm. It is kept until completely dry.
  7. The surface is generously lubricated with tar, several rows of brickwork are laid on top to the floor level, on which the construction of the furnace itself will begin.

Useful video

The specialist explains the intricacies of construction:

Options

The most common options for building a foundation are considered, proven by frequent use and quite reliable. In some cases, other types of foundations are used, for example, pile-slab. With this method, the monolithic slab rests on piles buried to dense layers of soil.

The good thing about this method is that the possibility of settling of the bedding and the butting layer is excluded, the piles stand firmly and motionless. Driven reinforced concrete piles or screw piles are used as piles, making it possible to independently screw them into the ground. The installed piles are trimmed (extended) to the required length and tied with a channel belt (grillage), which serves as a support for the slab.

Nuances that must be taken into account during construction

Experts advise maintaining reasonable proportionality in the ratio of the weight of the furnace to the power of the foundation. We must remember that the foundation itself is also subject to sedimentary processes that can upset the balance base, create a distortion or disruption of the plane. The thicker the butt layers, the higher the risk of sedimentary deformations.

Hence the rule: the foundation must correspond to the load. This applies to such types as monolithic, brick, rubble and slab foundations, which are, in fact, variants of the same foundation.

Pile foundations that require the use of equipment must be designed in advance and pile driving work must be carried out simultaneously with general work, otherwise the equipment will not be suitable for the work site. At all, all work on the construction of a bathhouse should be designed and carried out simultaneously so that one does not get ahead of the other. In this way, errors and inconsistencies in construction stages will be avoided.

Screw piles can be screwed even inside a finished building, if there is room for the gate to move. This option may be needed when constructing a stove in an already completed building or when reconstructing a bathhouse.

In conclusion, it should be noted that the issue of reliable and competent placement of the stove is quite complex and responsible, but it is necessary to understand it, since the safety of the entire building, the comfort and safety of people may depend on the correct actions. Before starting work, it is necessary to thoroughly study all available materials for the chosen construction method, find out the geological conditions of the area, and ensure compliance with building codes and regulations. This will ensure long and reliable service for your bath.

You may also need the following materials from the section on bathhouse foundations:

  • Height and depth of the foundation,
  • How to do it right and how to do it yourself,
  • How to fill correctly
  • Which foundation is better?

reference Information

Where to buy, order:

Sauna stoves >>>

Completion of foundation work

Ruberoid protects the brick from moisture, which, coming from the ground, destroys it.

As for the inside of the foundation for a Russian stove, it is done “under backfilling” (at first they simply lay stones, then use a liquid solution - pour the stones with it). The foundation for the stove is built from rubble, without reaching the level of the floor itself (finished floor). Leave 14-15 cm. Ordinary clay bricks are laid at the very top of the masonry, which occupy a whole row. The foundations for the pipe are constructed in the same way. Now it is necessary to arrange waterproofing. Most often they take roofing felt, which is laid in two layers. Both glassine and roofing felt will do. Another brick row completes the work.

The foundation for a brick stove should be made one row lower from the border of the finished floor. And in order to protect the stove mass from moisture, a waterproofing layer is laid, on which the last brick row is laid. This should be equal to the clean floor. In the case of installing a foundation under a pipe, the same operations are carried out separately. When laying corners, its correctness must be checked after 4 rows, better even after 3, which is done with a plumb line or using templates in the shape of a metal square.

You cannot connect the foundation masonry for a Russian stove with the walls of the room, since there is a possibility of destruction of the masonry if the walls in the house settle or the structure being built settles.

It is also desirable (and quite relevant) that the owner does not encounter the problem of laying pipes under the foundation. This is a rather serious and complex matter. Therefore, it is initially necessary to determine the location of utilities at the design stage. Then there will be no unexpected expenses in the house and you won’t have to change anything on the fly. The foundation for a Russian stove will meet all expectations, and there will be no need to reconstruct it for a long period of time.

Innokenty Andreevich Vlasov

Ivan, in this case you need to start from a 10 liter bucket. Fill a full bucket with sand and add 1/3 of cement, mix everything - 10 liters. or.

How is ready-mixed concrete calculated for 1 square meter of screed 5 cm thick? How much sand and cement will this require? So as not to buy too much. Want.

For different brands of concrete, if measured by volume, then only the ratio of sand and crushed stone to cement changes, and water is always taken exactly half of the volume of cement.

A few additions: 1. If you need to perform high-quality waterproofing with liquid rubber, it is advisable to use geotextiles over the entire surface. Consumption.

How and with what to make the upper border of the foundation cladding (natural stone, flagstone)?

Copyright 2014–2017, moifundament.ru

  • foundation work
  • Reinforcement
  • Protection
  • Tools
  • Installation
  • Finishing
  • Solution
  • Calculation
  • Repair
  • Device
  • Types of foundation
  • Tape
  • Pile
  • Columnar
  • Slab
  • Other
  • About the site
  • Questions to the expert
  • Editorial
  • Contacts

  • Foundation work
    • Foundation reinforcement
    • Foundation protection
    • Foundation Tools
    • Foundation installation
    • Finishing the foundation
    • Foundation mortar
    • Foundation calculation
    • Foundation repair
    • Foundation structure
  • Types of foundation
    • Strip foundation
    • Pile foundation
    • Columnar foundation
    • Slab foundation

Why do you need to make a foundation for a stove?

Every process and component in the construction industry plays a very important role. Failure to comply with the technology will certainly lead to the destruction of the structure in the very near future.

The lack of a foundation will soon affect reliability and safety. Therefore, if you plan to use the stove for a long time, then building a reliable foundation is an integral part of the construction.

An important condition is the independence of the base for the stove-heater from the main foundation. In this case, the weight of the entire building will not affect the resistance of this component. Otherwise, the weight of the stove and the weight of the entire structure will put enormous pressure on it, which can cause deformation and destruction.

For example, the average weight of a stove made of brick will be 500 – 700 kg, which is an impressive figure. And if you add the weight of the entire building, you can only imagine what kind of destruction the foundation will undergo in just a couple of months.

If this component is not present at all, then using the bathhouse for its intended purpose may not work at all.

Concrete

The classic base for a furnace is a concrete slab, which is made by pouring cement-crushed stone mortar into a deep pit.

Circuit and device

The general structure of the foundation is the same regardless of the type of furnace and soil; usually it is a solid base in the form of a cube, which is made from a large amount of concrete mortar. The base structure is clearly shown in this diagram:

The diagram shows the base that we calculated above for a stove weighing 1150 kilograms.

Materials and tools

To install a high-quality concrete foundation, a certain list of materials is required:

  • Cement;
  • Coarse sand;
  • Boards for formwork construction;
  • Crushed stone;
  • Waterproofing, which is ideally served by roofing felt or polyethylene film.

Also, to install a concrete foundation for a brick oven with your own hands, you need the following tools:

  • Container for preparing mortar or concrete mixer;
  • Bayonet and shovel shovels;
  • Measuring tools: tape measure, corner, level;
  • For making formwork: hammer, hacksaw, nails;
  • To install waterproofing, a construction stapler;
  • For laying the base, a manual tamper is used.

Preparation of the solution

The base for the furnace must be strong, so the concrete solution is prepared in the following proportions: 1 part cement, 3 parts sand, 5 parts crushed stone. This consistency can withstand large ovens for a long time.

Manufacturing instructions

  1. It doesn’t matter what kind of brick or concrete base is installed under the stove, it is initially necessary to dig a foundation pit for it. The depth of the pit depends on several factors: the mass of the stove, the type of soil, and the presence of groundwater. The width and length of the pit must correspond to the dimensions of the heating system and additionally have a certain margin of distance for the formwork. In order not to accidentally make a mistake, it is recommended to first prepare a drawing of the future concrete foundation.
  2. After this, formwork is installed, the dimensions corresponding to the final values ​​of the dimensions of the structure, according to the drawing and diagram, which should have been prepared in advance. Sometimes formwork is not needed - if the soil is very hard and does not collapse from external influences on it.
  3. After the formwork is ready, the waterproofing is laid, attached to the formwork using a stapler.
  4. Pieces of brick or large stones are poured into the resulting hole - this is necessary so that the resulting concrete slab under the stove does not sag and is well adhered to the ground, as shown in the photo below:
  5. Then the concrete solution is poured so that the base rises 6 centimeters above the floor. When pouring, carefully measure its evenness using a building level and level it to perfection.
  6. If it is possible to line the ground part of the foundation with brick or rubble concrete, this can be done this way:

Before installing the heating system, the foundation under the furnace should dry for about 10 days; during the first week, spray the concrete surface with plain water.

Foundation for a furnace, what is the role of soil?

Features of laying a stove foundation depending on the type of soil.

It is better to build the foundation for the stove on solid soils. These include, for example, granite (rock), limestone. They have great compression resistance and are resistant to negative temperatures and groundwater. Dense soils (for example, clay or sand) are also a solid basis for the foundation, if the moisture content in them does not exceed the permissible level. The difference between bulk ones is their loose and more varied composition. Therefore, such soil is removed until dense soil is found, or it is thoroughly compacted. Clay sandy soils, loams and sandy loams are well suited as bases for foundations.

Only on macroporous soils, which contain clay, but with large pores, it is impossible to make a foundation for a Russian stove, since the ingress of water liquefies such soils and they become fragile.

The foundation is laid in a soil layer with high humidity using strong materials (both artificial and natural origin), such as concrete, rubble stone and others, which are resistant to the destructive influence of water.

The foundation is laid in dense and dry soils using lime (or cement added to it) mortar. If the humidity is excessive, only a cement solution is required.

The bathhouse is an excellent means for spending fun leisure time and preventive health measures. But many novice builders have one very important task before building it - how to make a foundation for a stove in a bathhouse with high quality and without wasting resources.

Indeed, the construction of such a structure itself is not cheap, and if the use of materials is inappropriate, then such construction will cost a pretty penny.

In this article we will talk about the types of foundations for stoves, whether a foundation is needed for a stove in a bathhouse as such, and also consider its construction for different types of stoves.

Preparation

Before starting any land and construction work, you must definitely decide on the future type of stove. The need for laying additional foundation elements () may depend on the type of heat source itself.

It will perform a protective function and is suitable for baths that are used once a week, because in winter the ground freezes to a considerable depth and its homogeneity is destroyed.

Experienced experts recommend laying the foundation for a sauna stove no less than the depth of soil freezing. You can learn this parameter from building climatology; in the southern districts of Russia the figure will be about 60-70 cm, and further to the north it will increase.

An important factor for construction is the type of soil, it can be:

  • Sedimentary or alluvial. It is found in areas where previously there were reservoirs and is well suited for any foundation. If you come across porous clay, then you need to dig a little above the freezing level, because it swells greatly from water and expands when freezing;
  • Soil containing sand and gravel, least exposed to frost, it is perfect for any building;
  • Bulk soil, consisting of crushed stone or gravel, after a few years becomes a good basis for the foundation for a stove in a bathhouse. In the case when it is not “seasoned”, it must be thoroughly mixed with crushed stone and compacted;
  • Permafrost - northern Siberia, etc. In such a situation, the foundation must also provide good thermal insulation from frozen soil.

Important. It is not recommended to place such a foundation for a bathhouse stove closer than half a meter near walls and main structures. The fact is that if it subsides or gets washed away, it can damage these structures.

The dimensions of the base will depend on the dimensions of the stove itself, but it must protrude ten centimeters from all sides.

Construction for an iron stove

It must be said that although iron stoves are light in weight, they also need to build a foundation. The fact is that with even small distortions, such a device will wear out more, and only if there is a high-quality base, there is a guarantee of its long-term operation.

It should be noted that building a foundation for an iron stove in a bathhouse is a simple matter and can be done with your own hands; this requires:

  • Dig a pit of the required dimensions, with the required depth depending on the type of soil and location;
  • Then crushed stone is poured into the bottom of the hole and compacted. When compacted, this layer must have a thickness of at least 300 mm;
  • Next, cement mortar is taken and poured on top of the crushed stone. In a few days it will dry out and you will need to put waterproofing on it;
  • A layer of concrete is poured on top of it, and the resulting surface is carefully leveled. If you have bricks on hand, they will work well instead of concrete.

This foundation is solid and its price is reasonable. And the main thing is that it does not require much physical labor.

Brick oven base

Such stoves are heavy, so the foundation for them must be more massive. Note that it weighs up to 4 tons dry and about 8 tons wet. In order to approximately calculate this indicator, you need to multiply the weight of one brick by their number and add 40-50% to the weight of the mortar.

Important. The ideal option is when the foundation for the stove in the bathhouse is poured simultaneously with the laying of the foundation of the structure itself. In this case, it will be monolithic and more resistant to external environmental influences.

If you have non-heaving soils on your site, then a reinforced concrete slab with a thickness of 150-200 mm will be enough for you, but provided that it is completely monolithic (without voids). To increase the stability of such a structure, it is recommended to make piles; in this case, they can be made from asbestos pipes with reinforcement filled with concrete.

The construction instructions allow the use of roofing felt sheets as formwork in such conditions. To do this, they are rolled up and additionally reinforced and filled with concrete.

The piles are installed below the freezing point of the ground. A hole is dug under them, crushed stone is poured onto the bottom and compacted, and after that the pile itself is made ().

After a week and a half, a slab is laid on it, and then waterproofing is organized. A good option is metal screw piles. They are screwed into the ground in a short time, but their noticeable drawback is the price and the call of a team of specialists.

Concrete and rubble base for a brick kiln

The foundation for a sauna stove made of bricks can be made of concrete and rubble.

To implement this you need:

  • Carry out excavation work - dig a foundation pit;
  • Crushed stone is poured onto its bottom and compacted. It is recommended to make this layer at least 150 mm. If you have very heaving soil at the construction site, then it is better to apply another layer. It is made from sand and filled with water twice and only after that with crushed stone;
  • Next, work is carried out on pouring the foundation;
  • Work is being carried out to install waterproofing on the inside of the formwork; for this, rolls of roofing material and bitumen impregnation are used. Large stones are laid at the bottom and crushed stone is poured between them;
  • Cement mortar is poured over the stones so that at least 60 mm remains to the floor level. The surface is leveled and covered with roofing material to dry for two weeks.

Important. When building the base of the furnace, it is necessary to leave a distance between it and the foundation of the building. This is done so that during operation it can rise and shrink. If you neglect this advice, the oven may collapse.

Conclusion

Many craftsmen uninitiated in the intricacies of the construction process ask themselves the question: is a foundation needed for a stove in a bathhouse at all? As you can understand from this article, it is absolutely necessary, because thanks to it the oven is not subject to deformation processes. The latter can appear due to high humidity of the soil on which the bathhouse is located, as well as severe frosts.

In this article we looked at the details of the construction of several types of foundation; if you adhere to the above technologies during construction, you will be able to build a good bathhouse for many years (). In the video presented in this article you will find additional information on this topic.

A stove in a bathhouse is an important attribute, the quality of which determines the functionality and safety of the entire structure. Sauna stoves have special requirements: they must be fireproof and easy to use. One of the criteria for assessing the quality and safety of a stove in a bathhouse is the presence of a foundation for the stove structure and its proper arrangement.

Types of foundation for a stove in a bathhouse

The foundation for a sauna stove is a mandatory element. This is explained by the fact that a metal or brick stove puts a significant load on the floor in the bathhouse. The absence of a solid foundation will lead to deformation and destruction of the floor structure and the stove itself. Therefore, in parallel with the main foundation for the bathhouse, it is necessary to think about arranging the base for the stove.

In most cases, the following types of foundations for a sauna stove are used:

  • A monolithic concrete foundation is considered the most popular; it is poured simultaneously with the main foundation or as a separate structure. The depth of laying such a foundation for a sauna stove should not be large, so in most cases the backfill is made of sand, crushed stone or rubble.
  • The brick base is also a monolithic slab, laid out from several rows of bricks. The strength characteristics of such a foundation are at a high level, like those of a concrete foundation, but with some advantage. In particular, we are talking about the possibility of dismantling if necessary. However, it should be taken into account that on problematic soil prone to seasonal movements, the integrity of such a foundation may be compromised.
  • A columnar foundation can be called a rarity; it is erected in cases where the above options are not suitable.

Height of the foundation for the stove in the bathhouse

The foundation for a sauna stove can have three heights:

  • Above floor level.
  • At floor level.
  • Below floor level.

The first two options are used very often, so questions about them practically do not arise. As for the third option, it is used for two reasons:

  • Firstly, air intake to support the combustion process is carried out from the underground space. Consequently, oxygen combustion does not occur in the waiting room or rest room. A prerequisite in this case is the presence of ventilation holes that will provide air flow.
  • Secondly, thanks to increased air circulation in the underground, the floor in the bathhouse warms up much faster. This applies to both concrete and wooden floors.

It should be noted that air intake from the underground can be arranged for a metal stove on a foundation made at or above the floor level. To do this, a metal pipe with a damper is welded into the side of the structure.

Construction of a foundation for an iron sauna stove

The technology for creating a foundation for a metal stove in a bathhouse involves performing the following steps:

  1. First of all, you need to dig a pit. Its length and width should slightly exceed the parameters of the stove. As for the depth, it depends on the characteristics of the soil. Most often, the base of the sauna stove foundation is located below the soil freezing level, approximately 0.5 meters.
  2. The bottom of the pit is well leveled and compacted.
  3. Crushed stone is poured in a layer of about 30 cm, and it is also leveled and compacted manually or mechanically. Read more.
  4. Prepare a solution of 1 part cement, 4 parts sand and water. The resulting mixture is poured over a layer of crushed stone; the thickness of the cement-sand mortar can be several centimeters.
  5. The cement screed must be left for some time until the cement gains the necessary strength.
  6. Next, waterproof the screed, using strips of roofing material for this purpose (read in more detail). Such protection from the negative effects of moisture will extend the service life of the base of the sauna stove. As a result of these actions, a kind of cushion is formed under the foundation, which softens the destructive effect of heaving soil on it.
  7. To create the main foundation, a concrete solution is prepared, which contains 1 part cement, 4 parts crushed stone and 2.5 parts sand (we also have a detailed article on that). All components are mixed dry and water is added in small portions. The solution should have a uniform consistency of medium thickness.
  8. The concrete mass is poured on top of the roofing felt, the surface is well leveled and the horizontalness is checked using a building level.

It should be noted that the finished base for a sauna stove is located 0.3-0.4 meters below the floor level. Fire bricks are used to raise the foundation to or above floor level. On top of the concrete base, 3-4 rows of refractory brick masonry are made, and the masonry is carried out over the entire area, and not along the contour of the stove.

Brick foundation for a sauna stove

A brick oven is a fairly massive structure; it places a load on the foundation 4-5 times greater than an iron oven with similar parameters. Therefore, the foundation for such a structure should be stronger and more solid.

Foundation for a brick stove

The foundation for a brick stove is formed using the following technology:

  1. First, a pit is dug; its depth should be at least 0.7 meters. As for the width and length of the pit, it is important that they exceed the parameters of the main structure by about 0.2 meters.
  2. The bottom of the finished pit is leveled and thoroughly compacted.
  3. Next, pour sand in a layer of up to 0.2 meters, moisten it well and compact it using a vibrating plate or other device.
  4. Broken bricks, crushed stones or stones must be poured on top of the sand layer. The height of this layer must be at least 0.2 meters. The rubble material is well leveled, covered with a small amount of sand, spilled with water and compacted thoroughly. Sand should fill all the voids in the rubble layer, so it is added until the material remains on the surface.
  5. On top of the compacted layer of rubble material and sand, crushed stone of the middle fraction is poured to a height of up to 0.1 meters; it should also be compacted using special devices.
  6. Formwork made of wooden boards is installed on the formed cushion. If the pit’s length and width exceeds the stove by 0.1 meters on each side, then the dimensions of the formwork structure must fully correspond to the length and width of the sauna stove. The wooden formwork should rise approximately 15-20 cm above the ground level.
  7. A reinforcing frame is laid inside the formwork structure; steel rods with a diameter of 12 mm are used for its manufacture.
  8. Next, you should prepare a concrete solution using classical technology and pour it into the formwork with a reinforcing layer. Before pouring concrete, the formwork walls are moistened to prevent moisture from being absorbed from the concrete mixture. The solution is poured in layers of 0.2 meters until the top level of the wooden formwork is reached, the surface is well leveled and left for 21 days for the concrete to gain the required strength. During this time, the foundation should be protected from drying out.
  9. After this, the wooden structure is dismantled.
  10. Between the walls of the pit and the finished foundation for the brick sauna stove, a space of 10 cm was created on each side, which allows waterproofing of the base. For this purpose, melted tar is used, which is used to cover the side surfaces of the foundation in 2-3 layers.
  11. Then the free space is filled with fine gravel or coarse sand. These materials create a kind of drainage layer.

The need to insulate the foundation of a sauna stove

The question of whether or not to insulate the foundation of a stove in a bathhouse concerns almost every owner. However, the decision is made in each case individually. Before making a positive or negative decision on this issue, it is necessary to understand the purpose of thermal insulation of the foundation.

Firstly, the absence of a layer of insulation leads to the formation of condensation on the internal walls of the foundation in winter during the heating of a sauna stove, since in this case the temperature difference is quite large. The presence of moisture helps to reduce the service life of the foundation and reduces its strength characteristics.

Secondly, the heat-insulating layer compensates for seasonal soil movements, reducing the degree of destructive effects of heaving forces on the foundation of the stove in the bathhouse.

Thirdly, the insulated foundation does not thaw in winter when the furnace is fired, therefore, the likelihood of its destruction is reduced.

In any case, thermal insulation of the sauna stove foundation allows you to reduce fuel consumption.

In general, the technology for manufacturing a foundation for a sauna stove is not particularly difficult; doing the work yourself can significantly save material resources. However, to create a strong and reliable foundation, a sequence of actions is required. Otherwise, deformation of the structure and, as a consequence, further destruction cannot be ruled out.

The stove in the bathhouse is built separately from the main supporting structure.

And its parameters depend on the weight of the stove itself.

Foundation for a brick oven

Even a small brick stove weighs at least 480 kg, so the base for it is made solid.

The dimensions of the foundation for a stove in a bathhouse are selected based on the following rule: its width and length must be 200 mm larger than the stove itself - 100 mm on each side.

Sequence of operations:

  1. A pit is dug, the depth of which exceeds the level of soil freezing in a particular area.
  2. A sand cushion is built at the bottom of the pit. Its thickness is 150 mm. Sand can be compacted by spilling it with water several times and then adding it to the desired thickness. The last action should be to thoroughly moisten the sand layer.
  3. Now you can lay stone or broken brick on the sand. Laying is done in layers with careful compaction of each of them. In the end you should have a well-compacted 200mm layer of broken brick.
  4. Proceed with the next water procedure. It is necessary to spill the cake until the sand stops settling.
  5. A 100-mm layer of crushed stone is poured onto the brick block and compacted well.

Having prepared the pillow, proceed with installation. Its height should be such that the future monolith rises 150 millimeters above ground level. To strengthen the structure, a reinforcement cage () is installed in the formwork. After this, you can pour the concrete mixture ().

After the concrete has hardened, the formwork can be dismantled, and the side edges of the foundation can be treated with a waterproofing compound ().

If you are making the foundation for a stove in a bathhouse with your own hands, and there is no experienced craftsman nearby, remember one of the main rules: laying the stove can only begin after the monolith has gained strength corresponding to its brand ().

Foundation for a steel furnace

Manufacturers of steel stoves usually stipulate in the accompanying documentation the requirements for preparing the base for the product.

In general, the construction of a foundation for an iron stove in a bathhouse is carried out as follows:

  1. A pit is being dug half a meter deep. The dimensions of the foundation for the stove in the bathhouse are selected in accordance with the dimensions of the heater with a small margin around the perimeter.
  2. The pit is filled with crushed stone to a depth of 250 mm, compacted and poured with liquid cement mortar mixed with sand (for one part of cement you need to take 4 parts of sand). The solution must be poured so much that the top layer of crushed stone is completely covered with it ().
  3. A day later, before pouring the foundation for the stove in the bathhouse, waterproofing is installed on the surface of the screed - for example, by laying roofing felt in two layers.
  4. A concrete mass is poured directly onto the waterproofing layer (grade M200 is quite sufficient in this case).

After a week, the concrete will set, and it will be possible to begin building the podium. It serves to raise the heater above the level of the finished floor by 100 millimeters.

Burnt brick is suitable as a starting material. The podium can be made as a single unit with the foundation, but in this case you will have to tinker with the formwork.

Requirements for the base for a cast iron stove

Cast iron stoves weigh at least 200 kg, and together with stones and the chimney, the total weight will be approximately 400 kg. So the question - is a foundation needed for a stove in a bathhouse - is purely rhetorical: of course, it is needed.

The foundation for a cast iron stove in a bathhouse can be provided at the stage of erecting the foundation of the main building. It is being built just like under a brick stove.

It’s another matter if the thought of buying cast iron came to your mind when the construction was completed, and even the floor in the steam room was laid. How to make a foundation for a stove in a bathhouse in this case?

An acceptable solution in this situation would be to install the heater directly on the floor. To strengthen it, additional supports in the form of brick columns, screw piles, etc. can be placed under the beams (joists).

The installation site of the heater is laid out with bricks or lined with fire-resistant sheet material.

Video about the foundation for a stove in a bathhouse.


The stove is truly the heart of the sauna; without it it is impossible to create a steam room. Previously, the stove in the bathhouse was installed directly on the floor, but today completely different rules and regulations apply. Heavy, massive stone stoves that retain heat for a long time require a foundation. And here a number of questions and nuances arise that require coverage: what kind of foundation for furnaces is needed, how it is done, why it is needed. Correct calculations and adherence to foundation installation technology will help protect against possible misalignment of the stove, destruction of the chimney, or the appearance of cracks in the masonry of the stove itself.

The very first questions that arise are whether a foundation for the stove is really necessary and, if so, why.

First of all, whether a stove needs a foundation depends on its weight. For example, under a metal stove, the weight of which is usually no higher than 200 - 250 kg, does not require a personal foundation. It can be placed on a solid floor base. The exception is a wooden floor - sometimes it is preferable to make a simple foundation for a metal stove. This will reduce the fire hazard and also reduce the impact of the stove on the wood floor.

Brick oven can have different weights: from 500 kg to 8 - 10 tons. The most common option is a stove weighing 1200 - 1500 kg. Brick kilns weighing more than 750 kg require a separate foundation. This is primarily due to soil movements and settlement of the structure.

The structure of the bathhouse and the design of the furnace are subject to settlement, which depends on the distribution of mass over the area. Taking into account the design, a heavy massive stove will influence the foundation of the bathhouse unevenly with its weight and will press at the point of contact. As a result, the foundation will sag unevenly, and the structure of the bathhouse may become askew. To prevent this from happening, a personal separate foundation is built under the brick oven.

Important! The requirement to equip a separate foundation for the furnace is specified in SNiPs. However, there are exceptions. When these SNiPs were written, slab foundations had not yet been made everywhere, mostly only strip foundations. If a reinforced concrete slab is poured under the entire structure of the bathhouse, then a personal foundation for the stove is not needed.

When choosing the type of foundation, it is necessary to take into account the properties of the soil. For example, another reason why it is necessary to make a separate foundation for a stove in a bathhouse is the heaving of the soil during frost. The bathhouse is not always heated; quite often it is unheated. During this time, the soil under the bathhouse freezes and either expands or contracts, which is called heaving. As a result of heaving, the foundation under the stove can rise above the level of the foundation under the bathhouse itself. If the foundations were connected to each other and did not have a gap, then destruction and distortion of both the furnace and the building would inevitably occur.

How to make a foundation for a brick oven

The most important requirement for the foundation for a stove in a bathhouse is reliability and non-susceptibility to soil movement. To ensure this, you need to know exactly what type of soil the bathhouse is on and to what depth it freezes. If you do not have such information, then you should contact the geological service of your region, they have all the data.

Before making a foundation for the stove, you need to calculate its weight. The size of the foundation and its depth will depend on this. 1 m3 of brickwork weighs 1350 kg, this already includes the weight of the bricks and the weight of the cement mortar. To calculate the weight of the furnace structure, it is necessary to multiply the total volume of the masonry (furnace) by 1350 kg. A stove weighing 750 kg does not require a separate foundation. The base for such a stove can be an asbestos sheet. A sheet of asbestos must be laid on top of the floor on the clay mortar; a sheet of roofing iron must be laid on top of the asbestos sheet. This will be enough to insulate the floor and ensure fire safety. The dimensions of asbestos and iron sheets must exceed the dimensions of the stove by 25 cm on each side.

If the weight of a brick kiln exceeds 2 tons, then a buried concrete foundation must be installed under it. Also, the basis for arranging such a foundation can be the type of soil - porous clay or loess soil. Porous clay, saturated with water, expands greatly, especially when freezing. And loess soil, when wet, simply turns into slurry. Therefore, a foundation is built on such soils with a depth below the freezing point of the soil in winter.

Stages of work:

  • We dig a pit for the foundation. The dimensions of the pit should exceed the dimensions of the furnace by 10 - 15 cm on each side. The depth of the pit should be greater than the freezing level of the soil. For many regions, a depth of 1.5 m is sufficient.
  • We compact the bottom of the pit.
  • Add a layer of crushed stone and compact it as well. After compaction, the height of the crushed stone layer should be at least 15 cm.
  • We pour a 20-30 cm layer of sand on top. We spill it with water and wait until it seeps into the voids between the crushed stone fractions.

  • When the sand dries, pour another layer of crushed stone 15 - 20 cm thick. Compact it.
  • We install wooden formwork in the pit. We lubricate the inner surface of the formwork with hot bitumen or waterproof it in another way.
  • Inside we lower a reinforcing frame made of steel rod 8 - 12 mm thick.

  • Pour the concrete to a level 6 cm below the floor level in the bathhouse. We use the same solution as for the foundation of the bathhouse.
  • After pouring, check the horizontalness of the foundation surface.
  • Cover the concrete with film or roofing felt and leave to dry. It will take from 15 to 30 days.
  • After the concrete has completely hardened, remove the formwork.
  • We coat the foundation walls with waterproofing material - tar or any other. It is better to do this in 2 - 3 layers.
  • The space between the foundation and the soil walls, as well as between the foundation of the bathhouse, must be filled with sand.

Waterproofing the foundation surface can be carried out from above, before laying the furnace. Or maybe at the stage of building the foundation. For example, appropriate additives can be added to the solution. Or, at the stage of the last crushed stone filling, make a concrete preparation on top with a layer of only 2 cm of liquid mortar. When it dries, you can spread roofing felt or other rolled material on top in 2 - 3 layers. Concrete is poured on top of the waterproofing.

For a furnace weighing from 1 to 1.5 tons, you can get by with a shallow foundation. Especially if the soil on the site is continental or sedimentary, and the groundwater level is very low. If the region does not suffer from severe floods, then this type of foundation, as described below, will be quite sufficient.

Stages of work on arranging a shallow foundation for a furnace:

  • We are digging a pit for the foundation: the dimensions are 20 cm larger than the size of the furnace, the depth of the pit is 70 cm.
  • At the base of the pit we make an extension - a heel. On each side we expand the pit by 10 cm. This will make it possible to avoid soil movement.
  • Pour the sand in a layer of 15 cm. We spill it with water and wait until the water is absorbed and the sand settles.
  • Then add sand so that the total layer is still 15 cm. And fill it with water again and wait until the water is absorbed.
  • Pour broken brick, stone and crushed stone in a layer of 20 cm. Carefully level and compact.
  • Pour sand on top and spill with water. We wait for the sand to settle in the cracks between the stones. Add sand and fill it with water until the entire space between the stones is filled with sand.
  • Fill in a 10 cm layer of crushed stone and compact it.
  • Then we install the formwork inside so that there is a free space of 10 cm between the formwork and the walls of the pit.
  • We insert a reinforcing frame made of 8 mm rod inside the pit.
  • Pour concrete to the floor level in the bathhouse.
  • We check the horizontalness of the foundation surface.
  • Cover the concrete with film and wait for it to dry, about 2 - 3 weeks.

  • After the concrete has completely hardened, remove the formwork and coat the foundation walls with waterproofing mastic.

We fill the free space between the walls of the foundation and the walls of the pit with sand or fine gravel. Sand is preferable.

For highly heaving soils, a foundation in the form of a concrete monolithic slab on piles or pillars is also suitable. If you bury the pillars to a depth below freezing of the soil, little ground movement will be felt in winter. This option for arranging a foundation for a furnace is suitable for those regions where the soil freezes very deeply and making a full-fledged foundation to such a depth is simply not profitable.

On non-heaving soils, you can make a monolithic slab without columnar supports. After all, if the soil is subject to heaving, then the concrete slab will move along with the soil. And if it is also connected with the structure of the floor, then destruction inside the bathhouse cannot be avoided. It is to minimize the movement of the slab that pile or columnar supports are made.

Arrangement of a slab foundation on columnar supports:

  • The height of the concrete slab will be 15 cm. Therefore, we remove the top layer of soil to this depth. The dimensions of the pit should exceed the dimensions of the furnace by 15 - 20 cm on each side.
  • At the four corners of the pit, at a distance of 15 - 20 cm from the edge, we drill holes for the pillars. The depth of the holes is below the soil freezing level, diameter 20 cm.
  • Place 10 cm of crushed stone on the bottom and compact it.
  • We insert rolled roofing material into the hole. It will serve as both formwork and waterproofing of the columnar foundation.

  • We insert a frame made of reinforcement 8 mm thick inside.
  • We arrange formwork throughout the pit for pouring the slab. We also lower the reinforcing frame inside.
  • We fill everything with concrete. First the pillars, compacting the concrete with a vibrator, and then the slab.

Important! It is advisable not to take breaks between pouring the pillars and pouring the slab. Otherwise, the structure will turn out to be disconnected, but it needs to be monolithic.

After the concrete has dried, about a month later, we cover the surface of the slab with waterproofing material. After which you can safely equip the oven.

Slabs on screw piles:

  • Screw piles can be used instead of concrete pillars. They are screwed into the ground using threads. As a result, the soil is compacted and foundation settlement will be minimal.

The foundation on screw piles is stronger and more durable than on pillar supports. But more expensive. The concrete slab is poured on top of the screw supports using conventional technology. The height of the slab is 15 cm. Accordingly, the top of the screw piles must be buried to a sufficient depth.

Foundation for a sauna stove made of rubble concrete

The most common type of foundation for a furnace is rubble concrete. It is more economical than a concrete foundation, especially if there is a lot of construction waste left in the form of fragments of bricks or stones. Such a foundation can be installed instead of a buried concrete foundation.

  • We dig a pit for the foundation. Depth - 1 - 1.2 m. The dimensions on the sides are 15 - 20 cm larger than the dimensions of the stove.
  • Compact the base soil.
  • Pour crushed stone in a layer of 15 cm and tamp it down.
  • We install wooden formwork. We waterproof the internal walls.
  • We place large stones or bricks at the bottom, the maximum size of which is 15 cm. The total layer of stones is 20 - 30 cm.
  • We fill the voids with small crushed stone.
  • We prepare a concrete solution with a consistency like liquid sour cream and pour it over the stones. Concrete should fill all voids.

Important! If the foundation height is large, then the next layer of stones and concrete pouring can be done the next day. If the height of the foundation is such that 2 layers are enough, then everything can be done in one day.

  • The last layer of stones should end at such a level that there is 6 - 7 cm left to the finished floor.

  • We check the surface of the foundation for horizontalness. If there are deviations, then add concrete solution until the foundation is level and horizontal.
  • Cover the concrete with film and leave to dry for 2 - 3 weeks.
  • After the concrete has hardened, remove the formwork.

The surface of the foundation walls must be waterproofed with mastic material. We fill the space between the foundation and the walls of the pit with sand. In the future, the laying of the stove begins at a level 6 - 7 cm below the floor level.

Also, do not forget that between the foundation of the bathhouse and the foundation for the stove there must be a gap of 5 cm, which is best filled with sand.

How to make a foundation for a metal sauna stove

As already written above, sometimes a foundation is also made for an iron stove, although its weight is not that great. If the floor in the bathhouse is concrete, then there is no need to make a foundation for an iron stove. And if it’s wooden, then it’s not necessary, but it’s possible.

  • We dig a pit for the foundation of the furnace with a depth of 50 cm. The dimensions of the pit should be slightly larger than the size of the metal furnace - by 5 - 10 cm.
  • Pour crushed stone into the bottom of the pit and compact it thoroughly. After compaction, the height of the crushed stone layer should be at least 30 cm.
  • Pour the concrete preparation on top with a layer of 2 - 3 cm. Make the solution for concrete preparation as follows: 1 part cement, 4 parts sand, enough water to obtain a medium-thick consistency.
  • After the concrete preparation has dried, we lay a waterproofing layer in 2 - 3 layers.
  • Then we install the formwork.
  • We insert a reinforcing frame made of 8 mm steel rod inside.
  • Fill the concrete with a layer of 20 cm. Prepare the solution according to this recipe: 1 part cement, 2.5 parts sand, 4 parts small crushed stone.
  • We check the horizontalness of the foundation surface. If necessary, add and level the solution.
  • After the concrete has completely hardened, i.e. after 2 weeks, we carry out the laying of red burnt bricks, bringing the level of the foundation to the level of the floor.

Red brick can be laid both over the entire area of ​​the foundation base, and only as support columns. Also, the entire foundation for a metal stove can be made of brick.

The foundation for a stove is a responsible task. If you plan to order the laying of the stove from a specialist, then you should not make the foundation yourself. First you need to consult with the stove maker, and only under his guidance begin to build the foundation. Please note that an incorrectly made foundation threatens you with the fact that during soil movements the chimney will break the floors and roof. All this can lead to unpleasant destruction. Think through everything in advance.