We select and build a foundation for a bathhouse made of foam blocks: depth, types. How not to collapse a building

A reliable and high-quality foundation is the basis of the entire building, on which the entire subsequent “life” of the building depends . It happens that one foundation alternately bears several types of walls, which age, are demolished, and others are erected in their place. A low-quality foundation will not tolerate this; it will collapse on its own and ruin the walls resting on it. Therefore, only a properly designed and constructed foundation can serve for a long time and reliably.

Introduction

If you have not been involved in construction and the site is not familiar to you, then you do not know the characteristics of the soil, however, it will be quite easy to find out them even for a non-professional.
To do this, dig a hole from half a meter to one and a half meters deep. More specifically, this will depend on the level of groundwater. If you find peat, sand, or marshy soil in the resulting hole, this indicates that the soil is weak and that you should choose either a slab foundation or a pile-screw foundation, that is, one that is characterized by increased durability and reliability. A strip structure on a reinforced sand bed is also acceptable

But here it is extremely important to create a monolithic foundation, because the block version will simply be unreliable

If you find a lot of clay, loam, gravel, or medium sand in the soil composition, then the density of such soil will be average, which means that it is possible to choose a strip or columnar foundation. This type of foundation is ideal for baths of absolutely any type.

In the event that quartz, fairly dense fine sand or rocky rocks are clearly visible in the soil, then absolutely any type of foundation is perfect for such stable soil.

After a careful study of the soils, the selection of materials will follow. If you prefer bricks, foam blocks, natural or artificial stone or other material that consists of large stone-like elements, then the foundation in this case must be of a strip or slab type.

If you are attracted to timber or logs as a material, then it is advisable to choose a columnar structure. However, if the site has weak soils, then it is better to choose a screw foundation.

Insulation

Not applicable to columnar and pile-screw foundations and applies only to concrete foundations. Its meaning is to prevent the formation of condensation, which is absorbed into the concrete in the warm season and breaks it when the moisture freezes in the cold season. Insulation is carried out during the construction of the foundation. Materials for this can be polystyrene foam, expanded clay, more modern foam glass or expanded polystyrene. Insulation is carried out from the outside by sheathing the foundation with polystyrene sheets (the best option). You can insulate from the inside, although many professionals consider this method useless and even harmful, which is debatable. You can learn how to make external and internal insulation of a bathhouse from separate articles.

Concrete composition for a reliable foundation

The variety of concrete mixtures, even with a quick acquaintance, is simply off the charts. There are a lot of proposals - all that remains is to decide which concrete to choose. It is used to make the foundations of buildings, garages, bathhouses, fences, ceilings in basements, construct stairs, build load-bearing structures, walls, etc.

To decide which brand of concrete to use for the foundation, you need to know what basic indicators are decisive for the qualification of concrete solutions.

The photo shows the process of pouring a strip foundation

Binding components of concrete

There are 3 key indicators for the qualification of concrete solutions:

For binders;

Additives for concrete

Concrete with silicate additives. Lime is used and is rare in construction;

Binder additives for concrete

What concrete is best to use for the foundation, and how to mix it correctly

1. Cement concrete is the most common option, which is used for internal and external work, without which construction production from the foundation to the roof is indispensable;
2. Binders such as gypsum and clay can also be used to make concrete, but they are not used for pouring foundations.

Density of concrete

Foundations can be strip, slab, pile, columnar, so it makes sense to consider concrete according to the density of the batch, that is, according to the second key indicator:

The filler for heavy concrete is rocks, gravel, crushed stone.

• Modern construction life cannot do without heavy concrete: monolithic construction of buildings, prefabricated bridge structures, road slabs, foundation blocks, etc.;
• Which concrete to choose for the foundation is a clear question. This should be a heavy concrete mixture that has the following advantages:

1. Unique strength after drying;
2. The price is affordable for consumers;
3. Durability;
4. High density;
5. Convenient feeding and placement of material.

The constituent ingredients of heavy concrete are represented by cement, special additives, aggregate, clean sand, and water.

The composition of heavy concrete is calculated for 1 m³ and is divided according to strength class

What brand of concrete to make the foundation from:

• M500 - heavy concrete is used in the construction of subways and bridges;
• M400 - hydraulic structures, bank vaults and bridges;
• M350 - airfield plates;
• M250, M300 – pouring monolithic foundations;

Many people are also interested in the following question: is it possible to use lightweight concrete to build a foundation for a house:

• Lightweight concrete contains fillers of 2 groups - natural (natural) and artificially produced.
• Whether they are structural, heat-insulating, structural-thermal-insulating, lightweight concrete is not used for pouring the foundation.
• They are used for the construction of floor walls, load-bearing structures, thermal insulation, or perform a combined function that combines both of the previous ones.
• The only type of lightweight concrete that is used, for example, for the production of FBS foundation blocks is the option with expanded clay as a filler. But it is stipulated that its density must be at least 1800 kg/m3.

An option in which you can use lightweight concrete

Construction of a bathhouse

Creating a foundation

Since we are building a bathhouse from foam blocks, a strip foundation is enough for us. This is due to the fairly low weight of this material.

To do this we need:

Bathhouse foundation

1. Dig a trench 60 cm deep and 30 - 40 cm wide. It should exactly match the dimensions of our building.
2. Fill the bottom of the trench with sand or fine gravel. This is necessary for better drainage.
3. Make formwork around the entire perimeter of the trench. If the edges are fairly even, you can simply lay down roofing felt. This will prevent the outflow of water when pouring the foundation and moisture during the operation of the structure.
4. To reduce the solution consumption, you can fill the trench with rubble stone and fill it with concrete.

1. In some cases, it is recommended to reinforce the foundation, but in our opinion this is not necessary.
2. In the upper part, you will still have to perform formwork to raise the foundation above ground level by 10 - 20 cm.

Walling

The instructions recommend starting the process of building walls from foam blocks with your own hands 1 - 2 weeks after making the foundation, after the concrete has completely dried. But first it is necessary to waterproof the foundation. This can be done using two layers of roofing material, which is laid along the top of the foundation.

We build walls

Now you can proceed directly to laying the first row of foam blocks

Since it is extremely important for us that the first row is perfectly level, we lay it using mortar. Using a level and slopes, we achieve perfect evenness

The subsequent rows are laid using special glue.

Further construction of baths from foam blocks is no different from the construction of any other buildings:

• The laying is carried out with a row offset to the floor of the foam block,
• For door and window openings we use concrete or metal lintels,
• We leave a gap in the upper part for laying roof piles, this is especially true for small buildings.

Roof installation

This question largely depends on the type of roof you choose. It can be a single-pitched, double-pitched, multi-pitched or flat roof.

Roofs are also distinguished by the presence or absence of an attic space.

Which roof to choose?

• A pitched roof is good for the small amount of required materials and ease of installation, which you can do yourself. The disadvantages include a large accumulation of snow in winter and an insufficiently attractive appearance.
• The gable roof has a pleasant appearance, the presence of an attic space, which reduces heat loss, and a large angle of inclination, which prevents the accumulation of snow. Disadvantages include large windage, increased consumption of materials due to the need to equip the attic floor.
• A multi-pitched roof has the most attractive appearance and the price of such a roof is much higher. Otherwise, all parameters are the same as for a gable roof. The disadvantages include the high labor intensity of the work and the excessive consumption of materials for its production.
• A flat roof can only be used in places where there is no snow, otherwise its mass may push through the ceiling.

Since it is recommended to build a bathhouse from foam blocks correctly with a gable roof as the most optimal, we will briefly describe the stages of its construction.

Roof over the bathhouse

First of all, the attic floor is installed. To do this, floor beams are laid, and the distance between them is sewn up with wooden boards. Moreover, between the top and bottom boards it is necessary to lay a layer of waterproofing and insulation.

Since we decided to build a bathhouse from foam blocks with a gable roof, at the next stage we install rafters. We strengthen each of them using a post and a brace, and fasten them together using a crossbar and diagonal ties.

At the last stage, we sew up the distance between the rafters with a board, lay down waterproofing, insulation and roofing material. This completes the installation of the roof over our bathhouse.

Let's consider these “calculations and logic” in reality

There is no clear text in the regulations that allows or prohibits whether to build a foundation for a house from foam concrete. Below are the methods used by proponents of this material.

Citation of normative documents

Example:

“SNiP No. 31-02 - the foundation must correspond to the calculated strength values.”

Objection.

SNiP is a collection of norms and rules that are closely related to each other. The above quote means that ALL calculations must be in accordance with each other. You cannot take one indicator and rely only on it.

Proof.

Screenshot SNiP 52-01-2003

An example of “pull by the ears” based on one parameter - a duvet retains heat better than foam concrete. Let's build a foundation of fluff.

Allegedly “calculation” of the load

Carry out a “calculation” of the load in the style described below. For the foundation, it is recommended to use foam concrete, which has higher strength indicators than the grade used for walls.

Characteristics of foam concrete

As you can see, the maximum strength of foam concrete is 9.7 MPa = 97 kgf/cm2. Grade M100, mentioned in SNiP II-22-81* - 98 kgf/cm2. Everything fits together.

For the load-bearing walls of a two-story house, blocks of the D600-D800 brand will be used.

Weight and dimensions of foam concrete blocks

So:

• The average weight of one block will be 27.2 kg.
• One linear meter of wall will take 1000/600 = 1.6 blocks.
• With a height of each floor of 3m, a 6-meter wall will require 6000/300=20 blocks.
• Just for 1m.p. walls will need 20 X 1.6 = 32 blocks X 27.2 kg = 870 kg.
• In addition to load-bearing walls, the house also has partitions. Their thickness and density are smaller, but their area is always larger. In addition, all walls will have plaster.
• The resulting figure needs to be doubled. We get 870X2=1740 kg.
• With a block thickness of 200 mm, the mass of these walls will be distributed over an area of ​​100 cm X 20 cm = 2,000 cm2. Divide: 1740/2000 = 0.87 kgf/m2.
• The strength of foam concrete, 97 kgf/cm2, is 110 times higher! We’ll also reinforce it!

New walls cracked

Logical chain

They say that if the bottom row of the wall can be made of foam concrete, then the top row of the foundation can be the same, further along the chain.

A building and its foundation are two structures. Different forces act on the foundation and the building.

• Walls always press vertically on the base.
• The foundation distributes this load across the ground in many directions.
• Freezing soil presses on the foundation. In this case, freezing occurs only from the outside. The interior of the soil remains soft and does not provide support.
• Under certain places of the foundation, support may be lost due to soil washout.

“The house stands on a foundation” - this is how the sentence sounds correctly. Linking these two structures into one is incorrect, both from an architectural point of view and according to the laws of the Russian language.

Fight against shortcomings

A disadvantage of foam concrete is often recognized as a high degree of moisture absorption. As a method of dealing with the problem, it is proposed to make waterproofing.

The ability of foam concrete to absorb moisture

As you can see in the photo, foam concrete absorbs moisture very well. Being underground, any material is influenced by a huge number of factors. High-quality waterproofing with a 100% guarantee of protection will cost so much that the price of a foundation made of foam concrete blocks will no longer be attractive for the overall budget.

Protection of foam concrete on walls. What should it be like in the ground?

Negative examples of work performed

They claim that in the photo and video in this article they are building a foundation for a house from foam concrete. There are also step-by-step instructions on how to do this work yourself.

Of course, only with your own hands, because no design organization will undertake this! They will then have to bear the consequences. Here are some examples of such propaganda.

In fact, the photo shows not foam blocks, but FBS foundation blocks!

The indicated block length is 2400 mm - this is the standard length of the FBS block, which is made either from heavy concrete or dense expanded clay concrete. There are no foam concrete blocks of this size.

Foam block sizes

Site preparation

Any flat area is suitable for building a bathhouse. It is desirable that the soil is dense.

Get rid of all kinds of debris and start excavation work.

Get rid of all kinds of debris and start excavation work

As a rule, foam concrete baths are built on strip foundations. Dig a hole around the perimeter of the future foundation with a depth of 50-100 cm (depending on the characteristics of the soil on the site) and a width of about 30 cm.

Bathhouse placement options

Drive metal rods into the corners and along the perimeter of the trench (in increments of about 100 cm) and stretch a rope between them. This marking will make it easier for you to navigate when performing further work. Be sure to check the horizontalness of the prepared structure.

Tape

The strip type foundation is the most common in the construction of structures made of wooden logs or timber. It is used if the building site is dominated by stationary and low-moving soils. This type can easily withstand the light weight of the bath.

The use of a strip foundation will greatly simplify the construction of drainage from the bathhouse under the floor. In this case, there will be no need to equip the side walls of the underground space, as, for example, in the case of arranging a column-type base.

The main stages of work for constructing the belt

Calculation of the required amount of materials

At this stage, it is necessary to calculate the required volume of the finished cement-gravel mortar. To do this, multiply the height of the tape by its width and the length of the foundation along the perimeter. Then the resulting value must be divided by 5 and the result multiplied by the volume fractions of the substances included in the mixture.

For example, for a bathhouse 6*4 meters you need: 0.8 m (height of the foundation) multiplied by 0.3 m (width of the tape) and multiplied by 20 (length of the tape around the perimeter), resulting in rounding up to get 5 cubic meters of solution.

Information. The standard composition of the mixture is prepared in proportions (by volume): 1 (cement) * 1 (water) * 1 (sand) * 3 (gravel or crushed stone).

Marking the territory is carried out using a construction tape measure and half-meter-long pegs.

First of all, the long side of the future foundation is measured and fixed with pegs.

Then, using a construction harness, the location of the diagonal angle is found using simple mathematical calculations.

A peg is also installed there. All stakes are then connected with a cord with a slight stretch.

In order to ensure the accuracy of the obtained dimensions, it is necessary to measure the diagonals of the future foundation. They should be the same, maximum spread +– 2 cm.

Sequence of work during the construction of the belt

1. Digging a pit. Depending on the type of soil and the plane of the site, the depth of the pit can be from 60 to 80 cm, and the width - from 30 cm. Work must be performed carefully to avoid shedding of the side walls and displacement relative to the plane of the tensioned cord.
2. Installation of formwork. Its height can be 20–50 cm, depending on the level of the site on which construction is carried out.
3. Geotextiles are placed at the bottom of the pit to prevent mixing of the fractions that make up the cushion with the soil.
4. A layer of waterproofing is laid along the side walls of the pit and formwork. It could be roofing felt or another, more modern material.
5. Fine sand is poured into the hole to create a cushion. Its purpose is additional waterproofing and shock absorption of seasonal soil movements. The thickness of the layer is 15–20 cm. The sand is thoroughly poured with water and compacted with a vibrating plate or improvised means.
6. A reinforcing frame made of rods 12 mm thick is mounted on the resulting cushion. The frame should be double-row, with transverse struts made of reinforcement 8 - 10 mm thick.
   Special spacers for reinforcement or ordinary bricks are inserted under the bottom row to evenly position the frame in the thickness of the concrete.

When everything is ready, the concrete solution is poured

It is very important to carry it out in one go, without interruptions.

Otherwise, the base may crack at the joints and individual layers.

Important! When pouring the tape, it is very important to maintain a minimum distance of 3 cm from the reinforcement to any of the outer planes of concrete, which will help to avoid cracks and destruction of the reinforcement.

Work on the construction of the bathhouse can begin 3 weeks after pouring the foundation.

The strip type will be an excellent solution for building a bathhouse from timber, logs or a frame bathhouse. The only limitation here is swampy heaving soils, subject to horizontal seasonal shifts.

Compliance with construction technology is the key to a long-lasting bathhouse

In order for the construction of a bathhouse to be effective, it is necessary to follow the instructions and adhere to the technology.

Marking and excavation work

There are different methods for marking the area while respecting the scale of the building. But the principle remains the same: it is necessary to correctly determine the installation location

It is important to consider that you will need to install formwork, and then finish the foundation

Excavation work begins with the construction of a trench for the foundation. Its depth is determined by the approximate weight and height of the pillow.

Pouring the foundation

At the design stage, you need to determine the height of the base. Experts recommend raising it by at least 30 cm.

Further actions will be performed according to the following algorithm:

1. The bottom of the trench is compacted with greasy clay and compacted.
2. Next, a cushion of coarse sand, gravel or small crushed stone is arranged.
3. Construction of a frame with reinforced elements.
4. Pouring cement-sand mixture.

Waterproofing the base for masonry walls

In order for the walls of the bathhouse to remain resistant to moisture, it is necessary to provide good waterproofing of the foundation. It will prevent rapid wear of load-bearing structures and protect the room from all kinds of rot. Polyethylene, roofing felt or aluminum foil are used as a waterproofing material for a bathhouse with your own hands.

Construction of walls from foam blocks. Lintels over window and door openings

The process of building walls is not complicated, but its effectiveness is determined by several nuances.

First of all, builders need to inspect the material. Any external defects should be alarming, because... Over time, they will lead to the destruction of the supporting structure.

It is important to monitor the thickness of the solution

Features of the construction of floors and roofs. Roofing device

When arranging the roofing structure and covering the bathhouse, it is important to monitor the quality of the material. It should be light and have low thermal conductivity. A layer of expanded clay, sawdust or shavings is used as additional thermal insulation

But in order to prevent the rapid rotting of such raw materials, you need to take a responsible approach to waterproofing issues

A layer of expanded clay, sawdust or shavings is used as additional thermal insulation. But in order to prevent the rapid rotting of such raw materials, you need to take a responsible approach to waterproofing issues.

Installation of water pipes and sewerage

Work on the arrangement of the water supply and sewerage system depends on the purpose and time of use of the building. If you want to visit the bathhouse in winter, you need to provide protection for these units from freezing. Otherwise, the water will freeze and lead to failure of the entire system.

A complete water supply consists of the following elements:

1. Pipes connecting to hot and cold water.
2. Water heating device.
3. Pump with filter elements.
4. Emergency drain system.
5. Water supply line to the tank.
6. All kinds of additional parts: valves, taps, pressure gauges.

Floor construction

The floor structure in the bathhouse is created from high-strength materials that can remain resistant to moisture. In addition, they should have a comfortable surface and retain heat well. In most cases, the floor in a two-story bathhouse is made of wood.

Waterproofing and vapor barrier of walls

To construct hydro- and vapor barriers, polyethylene film, roofing felt, aluminum foil or other modern materials are used.

Furnace laying

The stove in the bathhouse can be brick or metal, but the first option preserves all the traditions of the classic Russian steam room, so it is in great demand. Laying a stove is not a complicated process, but if you lack experience, it is better to entrust the task to a specialist.

External and internal wall decoration

When constructing a bathhouse yourself, it is necessary to pay due attention to the external and internal decoration of the walls. This is necessary to improve thermal and waterproofing. 

Foam block foundation

Many developers have a question about why it is not recommended to build a foundation of the same material for light walls built with their own hands from foam blocks. On the one hand, small loads from the load-bearing walls of a one-story bathhouse make it possible to get rid of a massive underground structure. On the other hand, frozen soil will have an irreversible effect on the fragile foam block under the influence of frost heaving forces, quickly destroying the foundation.

It would seem that in the southern regions, where the air temperature does not drop below positive levels, the construction of a bathhouse on a foam block foundation is quite possible. But here groundwater or heavy rains can play a role. In this case, it is possible that even the most advanced waterproofing will leak at the slightest opportunity and the porous concrete will begin to intensively absorb moisture, which will subsequently lead to the need to strengthen the underground part of the bathhouse.

However, there are daredevils who build bathhouses on a foundation made of foam blocks with their own hands. There is also evidence that similar technology is being used in some Western countries. In this case, several rules must be observed:

the location of the groundwater level should be much lower than the base of the foundation; when laying, reinforcement elements should be used; when choosing blocks, you need to pay attention to materials with high density; It is worth taking care of impeccable waterproofing, which allows you to reduce the increased hygroscopicity of the material to zero.

Most often, foam concrete blocks are used as an auxiliary material in foundation construction. They fill the space at the base of the building, located above the ground between piles or pillars that take on the load-bearing load. But in this case, the masonry should be provided with reliable waterproofing.

Walling

When we build a bathhouse from foam blocks, we must understand that the laying is carried out similarly to ordinary brick, however, due to the large dimensions of the foam block elements, the process is much faster.

Armed with the necessary equipment, we begin laying the walls. Using a level, the highest fundamental angle is found. This is where the laying will begin.

For the steam room, a foam block marked M25 is selected. The blocks are fastened with a conventional cement-sand composition. They are placed on the edge.

After laying out the first row of elements, you need to check everything for level. The operating conditions of the finished object depend on the correct laying of the first row.

The second row is laid with a shift. The elements are attached with a special adhesive composition for working with porous materials. It is applied in a layer of half a centimeter.

A reinforcing mesh with a fine mesh is placed on top of every 3rd row of blocks.

During installation, door and window openings should be left. After completing this stage, the building is left for three days.

Depth for timber construction

As you know, saunas made of timber are the most optimal, reliable and lightweight structures that you can confidently make with your own hands. In this case, it is worth noting that you can choose certain foundation parameters, depending on the following points:

1. Base load;
2. Availability of groundwater;
3. Soil type;
4. Freezing depth;
5. Soil density.

Also, it is possible to build the following types of foundations for a timber bathhouse:

1. Strip base (on fertile or marshy soils);
2. Columnar (if there is clay, coarse sand or gravel);
3. Another type (if there is dense sand or rocky soil).

Important! If you do not want to “miss” the choice of the type and depth of foundation, it is better to do a soil analysis in advance - it can be ordered from specialized organizations

When choosing a columnar type, the depth should be about 1.5 meters for the middle strip. In other cases, it is taken into account that it should be 0.3 m below the established level of soil freezing.

The tape version was discussed above - the depth depends on the weight and the need for a deep base.

Advantages and disadvantages of cellular concrete

However, it’s worth starting with the material itself from which the walls will be built. It can be called "hardened concrete foam." Such foam can be obtained either mechanically by mixing concrete with a foaming agent, or through a chemical reaction with aluminum powder in an autoclave. In the first case, foam blocks are obtained, in the second - gas blocks.

Cellular concrete has common advantages: it is light weight and moderate in price. In addition, they are easy to cut even with a hacksaw. Their disadvantages are somewhat different: foam blocks have a closed cell structure, so moisture spoils only the surface layer, where the cells are open, while aerated concrete has a cell structure like foam rubber, so it can be completely saturated with water. During construction, it is usually believed that all cellular concrete must be well insulated from moisture, especially when it comes to building a bathhouse.

However, in our case, only one characteristic of these concretes is of interest: their lightness. Because the weight of the walls is part of the total load that falls on the foundation, and therefore determines its required strength. If the walls weigh little, then the foundation can be made lightweight. And here are the following options:

Depth depending on soil type

Before carrying out technical work on installing the foundation for the bathhouse, it is necessary to conduct a geological survey.

Depending on the identification of the exact type of soil, its load-bearing properties, the possibility of changing quantitative parameters as a result of tectonic changes, the best material for the foundation is determined, and most importantly, its depth is calculated. Correct calculation of the burial depth, in some cases, will save the foundation and walls of the bathhouse from subsidence, cracks, distortion, and deformation.

Fine and dusty sandy soils contribute to strong shrinkage of the bathhouse foundation. To reduce or level out this process, the depth of the foundation can be significantly increased. Instead of the planned 50 cm depth, it would be advisable to increase it to 70-100 cm. With increasing foundation depth, the compression resistance increases proportionally. This value in fine sands is approximately two times lower than in coarse sands. In order to make up for the missing load-bearing capacity, the depth of the foundation is doubled.

Gravelly and coarse sandy soils are quite reliable in terms of load-bearing qualities. Sandy soils are not heaving, so regardless of the amount of precipitation per year or the depth of freezing, you can choose any type of foundation for a bathhouse. Coarse sandy soils exhibit insignificant shrinkage compared to fine ones. On them it will be easy to build a shallow foundation, ranging in size from 20 to 50 cm.

Sandy soil does not retain water, which means it is a light soil. A pile or columnar foundation can be built on it. The depth of the pillars is approximately 1.5 m.

Rocky soils have the best load-bearing qualities of all other types of soils. They practically do not shrink, supporting the weight of fairly large-scale structures. Rocky soils are not heaving because they do not retain water in their pores. The depth of soil freezing will not be taken into account when building the foundation. There is no excess moisture in the soil, so they will not expand due to the conversion of water into ice. On rocky soils, foundations can be installed more economically.

Rocky terrain acts as an unshakable foundation for a building, so shallow or shallow foundations (less than 20 cm) are always built there.

Clay soils, unlike most others, have a finely porous structure. The main disadvantage of clay soils is their ability to swell. The proximity of groundwater and abundant rainfall contribute to the rapid accumulation of water in the pores of the soil. With the onset of sub-zero temperatures, water turns into ice. The density of water, after turning into ice, increases, which leads to an expansion of the volume of the entire soil. Changes in soil volume place additional load on the foundation, causing its deformation, cracking, distortion, and lifting of the bathhouse building.

Calculations for deepening the foundation on clay soils are carried out taking into account the freezing depth. It is necessary to build the foundation below the soil freezing level, then the loads will be exerted only on the side walls of the foundation, eliminating pressure on the base of the foundation. For example, the depth of soil freezing is 1.5 m, which means the foundation lies at a distance of 1.6 m. The high level of groundwater will not allow the necessary deepening of the foundation.

The base of the foundation is at an indentation of no lower than 0.5-1 m. Sufficient distance will be required in case of capillary rise of water in the soil and in case of an unexpected increase in water level due to heavy floods or prolonged downpours. To drain excess water from the ground, a drainage system is installed around the foundation. They dig a trench deeper than the base of the foundation. They lay the foundation around the perimeter with a pipe and lead it into the inspection well. Water will not accumulate and freeze in the pores of the soil, and excess water will also be automatically drained in the event of a strong rise in the groundwater level.

When installing a drainage system, the depth of the foundation can be changed, taking into account the load-bearing properties of the soil and non-tectonic parameters, which are also important for calculating the depth of the foundation for a bathhouse.

What stones are best for a bath? You will find out the answer to this question by reading this article.

And this article talks about metal sauna stoves.

Steam room finishing

All foam block elements are impregnated with a composition with moisture-repellent properties and covered with a waterproofing film. Next, the steam room is insulated:

• The foundation is insulated using mineral wool.
• The underground floor is covered with expanded clay and slag.

A ventilation hole is made at the base of the steam room to prevent excess moisture from accumulating.

The inside of the bathhouse is finished with wood materials. An excellent option would be pine lining. All boards are treated with an antiseptic.

For floor surfaces, it is better to choose ceramic tile elements.

The selected stove unit is mounted on the floor if it is a metal stove, and on a separate foundation in the case of brick models.

The photo of a bathhouse made of foam blocks shows that due attention should be paid to the interior design, choosing attractive, comfortable benches, tables, and shelves.

How to calculate?

Now let's talk about how to calculate the dimensions of the foundation and calculate its dimensions. And in different cases, calculations will be made differently. For example, to calculate the volume of a strip base, you need to know such parameters as:

• length;
• height;
• width of the planned structure.

The width will depend mainly on the area of ​​the support, and is usually in the range of 450-500 mm. And the height of the structure for a building of 2 floors, as a rule, is about one and a half meters. The length in this case will be calculated as the perimeter of the base of the building.

For example, for a building 6 by 9 meters, where there is one load-bearing wall having a length of 7 meters, the perimeter will be 37 meters. It will be calculated in this way: (7+ (6+9) *2). With a foundation width of half a meter, 27.75 cubic meters of concrete solution will be required. This value was obtained as a result of the following actions: (0.5*37*1.5). This formula is universal and is suitable for houses with an area of ​​10x10 meters or any other.

If we talk about a slab foundation, then in this case the volume of the base is calculated taking into account the area of ​​the structure and the thickness of the slab itself. Usually its thickness is at the level of 15-18 centimeters. With a building area of ​​54 square meters, 972 cubic meters of concrete solution will be required.

Fundamental arrangement

When constructing a bathhouse foundation, it is worth taking care of the sewage system. It is worth making a channel that is inclined towards the location of a hole or other collection point for all wastewater.

Next, when laying out the flooring, a hole will be left. It is through it that water is discharged into the sewer pipes.

Afterwards, the trench bottom is filled with a mixture of gravel and sand, this layer is compacted. Reinforcing mesh is laid on top. A horizontal bundle is made from steel wire.

Next, formwork is installed from boards 3 cm thick and 10 to 15 cm wide. The gaps between the laid boards should not be more than 2 mm. And the height of the formwork is chosen so that the future foundation is 5-7 cm lower than the level of the panels.

Concrete is poured in even layers. Then you need to make several holes in it so that the air can escape.

The formwork remains until the concrete is completely dry, approximately 3 to 5 weeks. After dismantling the formwork, the resulting empty openings are filled with mortar.

A layer of waterproofing in the form of roofing material is laid on the already dried foundation.

DIY foundation for a garage made of foam blocks

Building a garage foundation out of foam blocks yourself can be a daunting task for a newbie. But if you follow the instructions and recommendations of experienced builders, then this task will not be difficult at all.

Despite the fact that there are several types of foundations, the strip foundation has been and remains the most popular for small buildings. Therefore, we will talk about it below.

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Design

Any construction begins with planning and creating a project, the garage is no exception. Without a clearly thought-out, systematic action plan, there is no point in starting construction. It is at the planning stage that the type of foundation is selected, which means it is necessary to take into account exactly those factors that are listed above. The project should represent not only a plan for the foundation, but also for the entire structure. This makes it easier to achieve accuracy and correctly calculate the amount of materials.

A garage project can be developed using a computer program. In it you can not only create a visual model of the building, but also calculate the necessary materials.

Preparation

Don't underestimate the importance of preparatory work. Preparation for construction of the structure includes the following activities:

• A few centimeters of soil are removed and the site on which construction will take place is leveled.
• Pegs are driven into the corners of the future building.
• A rope (construction or nylon) is stretched between the pegs. The angle between the threads must be strictly 90°. If you are doing this for the first time, it may not work out the first time, but you need to try and achieve the ideal value.

Groundwork and filling

After the preparatory work comes the most important and crucial part: the process of laying the foundation itself. To make it more clear, we will talk about each action point by point.

• Along the perimeter of the future building, focusing on the stretched threads, a trench of the required width and depth is dug (what dimensions are most suitable is determined at the construction stage). The most commonly used dimensions are: depth - 50-80 cm, width - 40-50 cm (width of foam blocks plus 15 cm).
• A sand and gravel cushion is laid. To do this, the earth in the trench is compacted and 10-15 cm of sand and 7-10 cm of crushed stone are poured on top.
• The formwork is being installed. As a rule, formwork is made from available materials: wood, metal, etc.
• Next, the foundation is reinforced - a reinforcement cage is laid. It is mounted from reinforcement rods with a diameter of 14-16 mm; rods of 8-10 mm are suitable for the bundle. This frame is laid on a sand and gravel bed.
• After laying the reinforcement, you can prepare the concrete mixture. For it you will need: sand, water, cement mixture. Be careful, some store-bought mixtures already contain sand and only need to be diluted. You can mix the components either in a stationary concrete mixer or manually. But given that the foundation requires a fairly large amount of cement, it is better to get a small concrete mixer, or, as an alternative, rent it for the duration of the work.
• The final stage is pouring the concrete mixture into the trench. The solution should be poured evenly so that there are no complications later when constructing the walls. After pouring, the foundation should be left for several days until completely dry. Only after this can the formwork be dismantled and further construction work begin.

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A strip foundation is the most common type of foundation for a garage made of foam blocks. It is quite durable and can withstand the loads of a small technical room. In addition, it is easy to lay with your own hands. It is the possibility of self-construction that is often the decisive factor for many garage workers. After all, when building with your own hands, you have the opportunity not only to save money, but also to do everything conscientiously and in accordance with your wishes and plans.

How rational is it to choose the foam block option?

Let's look today at how rational the choice of building a house from foam blocks would be. What pitfalls can we expect, what should we pay attention to, and what is the approximate cost of building a house from foam blocks.

What determines the choice?

Before we get to the calculations and construction, let’s try to explain why we chose foam concrete to build the house. And in order to answer this question as accurately as possible, we will consider both the positive and negative aspects of this material.

Advantages

First of all, let's note environmental friendliness

This is a porous material, it takes a very long time to heat up and gives off heat for just as long. This will play a role in heating the room.

Easy to use. Considering that for the most part we want to save money, the option of self-construction is exactly what will allow us to do this

It is important that foam blocks are quite easy to work with, and the basic principles do not require special knowledge of masonry.

An example of a foam block product of different dimensions

Flaws

Negative qualities, we will definitely encounter some of them during our work, so we will also announce this list, although it is not large:

• Necessity of finishing. On the one hand, this is a completely logical continuation of construction, on the other hand, it always slightly increases the overall estimate.
• High hygroscopicity. This property is not necessarily negative in the true sense, however, in our case, if we do not waterproof the base, there is a risk of significantly reducing the service life of the house.

The scales have definitely tipped towards the choice of this particular material, mind you!

Projects

The situation with projects of foam block houses and cottages is ambiguous. Of course, the project is necessary; without it, you won’t be able to obtain any permits for the construction of the house itself, but this is also an additional cost.

In general, let’s say we can’t do without this, but how much house designs made from foam blocks and the cost of construction can cost us is a question directly for the designers.

Small house project

There are, for example, ready-made drawings, fully developed and adapted to specific terrain conditions and soil. Such projects may be assessed separately.

Some designers prefer to work based on the square footage of the future building. That is, we pay for every square meter.

It is difficult to give specific figures for the project; it will be easier to contact several design bureaus and get price lists from them.

Option of a house with construction calculations

Now we won’t go through the materials so much, we’ll just leave them as a “snack”, but consider what the financial component of the building itself depends on:

Project

Just as for any construction, before you start building a bathhouse, you need to choose a location, carefully plan, select and calculate the necessary material. Also find out what the roof will be like, for example, pitched.

It is advisable to immediately imagine what you want to see in the layout of your bathhouse. In the classic version, the drawings of almost all baths include a steam room and a sink; a relaxation room is also desirable. In different cases, areas are distributed according to emerging requests. There may be options with a large steam room and a small sink, also with reverse distribution, a large relaxation room is possible and many other options.

Choosing the appropriate option will not be difficult. Each person has his own idea of ​​the functionality, proper use and organization of the premises of the building being built.

Particular attention should be paid to the construction of the vestibule if you plan to use the bathhouse for its intended purpose in winter

Also, the location of the doors is of no small importance; they must be planned so as not to take up too much space.

The stove must be selected taking into account the volume of the steam room, not forgetting that it is usually heated from the dressing room, therefore, part of the heat is spent on heating it. Based on these parameters, the furnace power is selected.

Currently, the bathhouse serves not only for washing, it is often used for emotional and psychological relief. Based on the requirements, a construction project is selected and implemented.

It may include not only the classic set: steam room, wash room, locker room, but it may also include the premises of a relaxation room, terrace, attic, swimming pool.

The most economical option would be to implement a project to build a bathhouse with three rooms.

There are a great variety of bathhouse designs, the most common of which are those where the rest room is combined with a locker room. At the same time, it is advisable to make it larger than other rooms, due to the placement of the necessary furniture in it.

Plans for bathhouses with terraces are very common. The terraces are equipped with the necessary furniture in the form of chairs and tables, barbecues and barbecue ovens are installed. The building is built under a single roof and has an appropriate design. Instead of a terrace, you can add, for example, a garage or another extension. The original idea is a country house combined with a bathhouse building.

Quite often, an attic is built as a second or third floor. This two-story building can be used as living or guest rooms or for relaxation after procedures. Such structures can also be one-story. The most commonly used sizes are 6 by 4, 3 by 5, and 6x6 meters.

You need to approach the selection of a construction site with all responsibility. The site must comply with all fire safety rules and the requirements of SNiP 30-02-97.

Based on these requirements, the building must be located at a distance of one meter from the fence, while the distance to the neighboring house must be at least eight meters, including five meters to the border of the site.

Steam room roof

When building a bathhouse from foam blocks with your own hands, you can make the roof a regular gable one. When choosing the length of the rafter legs, you should focus on the slope angle, the width of the steam room and the conditions of the climate zone.

For areas with prevailing wet weather, it is recommended to make the roof slope angle 50 degrees.

The rafters are tied with staples, the beams are fixed a meter apart. When the rafter legs are installed, the sheathing is formed. Its type depends on the roofing material:

• for roofing felt sheets - double;
• slate sheets – single;
• for tiled elements - from 5 by 5 timber.

The roof is insulated, covered with vapor barrier material and moisture protection. At the end the roofing material is laid.

Depth for a foam block building

To build a foundation for such a bathhouse, it is worth preparing all the materials. It should be noted that foam blocks are a very light material, so there is no point in making a strong foundation. In this case, usually a tape version with a sand base is prepared, onto which a waterproofing material is then applied, with the help of which the base will be reliably protected from moisture.

For the construction, it is recommended to dig a trench, the depth of which should not be less than 60 centimeters.

The width may vary, but the optimal width is 35-40 centimeters. In this case, it is better to use reinforcement with a diameter of 12 mm.

Preparatory work

The site for the future steam room should be selected as level, where the soil is quite dense. This place must be cleared of various debris, after which you can proceed to work on the ground.

The construction of a bathhouse made of foam blocks is carried out on a strip-type foundation. To create it, you should dig a hole around the entire perimeter of the building, the depth of which is from 0.5 to 1 m, and the width is 30 cm.

Metal rods are driven throughout the entire trench and in each corner in 1 m increments. Then the rope is pulled. Be sure to check the horizontalness of the entire structure.

What types of foundations can be built from foam concrete?

Thanks to the structure and strength of high grades of this material, which are not inferior in strength to ceramic bricks. It can be used to construct the following types of foundations.

1. A shallow strip foundation with pile supports.
2. Strip foundation.
3. Columnar foundation.

After production, foam concrete undergoes a hydration procedure. That is, it should be stored for a month in a dry, well-ventilated area without load. During this process it gains its full strength. And only after this the foam blocks can be used to lay the foundation.

Setting up a strip foundation made of foam blocks with your own hands is relatively easy and much faster than pouring it with concrete or laying it out of brick. Rigidity is easily increased by reinforcing rows of foam blocks. Laying a strip foundation occurs as follows.

• First of all, the marking of the future structure is carried out. To begin with, mark the corners of the building along the outer perimeter. At each corner you need to drive a stake and connect all the corners together with a cord. This will be the outer perimeter of the future building.
• The next step is earthworks. It is necessary to dig a trench along the perimeter marked with a cord. As a rule, for residential buildings to the depth of soil freezing. For other rooms, 120 - 90 centimeters is sufficient. And the width is 10 - 15 more than the future wall.
• Then it is necessary to dig trenches for the load-bearing walls of the building.
• When the trenches are ready, a bed of gravel and sand must be poured onto the bottom. Sand first and compact firmly then gravel. On top of the pillow you need to make a cement screed about 15 centimeters thick. On the base of the concrete screed, you need to lay reinforcement of at least 8 millimeters thick. In three threads. Then let the screed harden for 7 to 14 days.
• After the screed has completely hardened, waterproofing is laid on its surface. This could be plastic film, roofing felt, and so on.
• And already on the waterproofing layer you can lay the first row of foam blocks on the foundation. After laying it on the first row, it is necessary to make a groove 15 mm deep and 30 mm wide. And in this groove you need to lay reinforcement along the entire perimeter of the row.
• The second row is laid on the first row using a fastening material (cement mortar or special glue), and so on.
• When the required number of rows has been driven out, the foundation must be carefully insulated from moisture using a waterproofing material.

Such a foundation can be used to build one-story houses made of foam concrete, garages, bathhouses, and so on. For heavier buildings, this type of foundation does not have sufficient rigidity.

Types of building materials

When making foundation materials, two types of foaming agent are used - organic and synthetic. Organic contains hydrolysates of proteins of plant and animal origin.

This material gains increased strength, but suffers from thermal insulation characteristics. When adding a synthetic foaming agent, tree resin is used. The thermal conductivity of such blocks is lower, but the strength characteristics are worse.

Reference! To build a base for a sauna, it is better to choose blocks of increased strength.

Several foam concrete parameters that are suitable for foundation construction:

• brand – D800-D1000;
• length – 600 mm;
• width – 200-300 mm;
• height – 300 mm;
• strength – 27-50 kg/cm2;
• thermal conductivity – 0.21-0.29;
• frost resistance – F50-75;
• vapor permeability – 0.11-0.14.

Foam blocks of this brand weigh on average from 31 to 40 kg. Several workers can lift such a weight, so it makes no sense to order special construction equipment, which allows you to save on construction.

Recommendations

There is a large selection of foundation base designs, each of which has a number of advantages and disadvantages. It is impossible to choose the best option, because the choice of foundation depends on the characteristics of the territory. When constructing the foundation, consultation with professionals is necessary, because the length of the service life of the bathhouse depends on the proper construction of the foundation.

The layer of sand and crushed stone must be protected with a layer of geotextile. This material can be laid between layers of soil, bending the edges upward. Textiles will protect the pillow from silting and erosion. The material allows moisture to pass through well, and due to its composition it is not subject to destruction for a long time. Geotextiles are produced in special rolls, which makes them easy to use.

Water must be drained from the bathhouse. For this purpose, a special drain is installed that goes into the ground.

You will learn further where to start building a foundation for a bathhouse.

What parameters need to be taken into account when choosing a foundation for a block house?

This relatively new material has many advantages over its analogues:

• ease;
• hygroscopicity;
• high sound and heat insulation properties;
• environmental friendliness;
• non-flammability.

The foundation for a house made of foam blocks is built with your own hands according to the same principles as the foundations for any other buildings. When choosing the type of foundation you need to pay attention to the following parameters:

1. Soil characteristics. These include freezing depth, soil composition, and groundwater level.
2. Estimated load. This includes the weight of the building itself, including its underground part, the weight of furniture, communications, and residents. When calculating the load, an adjustment must be made for the additional load from precipitation - rain and snow. It is at this point that the advantage of expanded clay concrete blocks, which have much less weight than conventional brick, will be visible. Consequently, a block house requires a less capital foundation.
3. The cost of the material, as well as the timing of laying and standing of one or another type of foundation.

Influence of soil parameters on choice

Let us note right away that you should not try to save money on the construction of the base. This saving can create a lot of problems in the future. An improperly laid foundation can cause walls and floors to break, the house to slope, and dampness and mold to grow inside the building.

Scheme of laying a foundation made of foam blocks

Ordering a 3D model of the soil on which construction will be carried out is quite an expensive undertaking, and not everyone can afford to turn to specialists. If your neighbors built not long ago and conducted a soil study, you are in luck. You can use their calculations. It is unlikely that the data will differ much within small areas. If this is not possible, we will try to do everything ourselves.

To do this, you need to drill a well (preferably several) up to 2.5 meters deep, not forgetting to take soil samples every 20-30 cm. This way you can understand what type of soil you will have to deal with and what the depth of the groundwater is.

If the soil is not heaving, then the soil freezes shallowly. Provided that groundwater flows at a level of at least 2 meters, you can opt for a shallow foundation. It is the least financially expensive and easier to build with your own hands.

For close groundwater and heaving soils, it is better to use more permanent types of foundations.

Screw piles

Sometimes a more expedient option for installing a foundation for a bathhouse is to install screw piles. Often in difficult soil conditions they become the only alternative to pouring shallow tape.

Metal piles are screwed into the corners of the building, and, if necessary, between them, with the involvement of relatives or neighbors, even without the use of mechanized equipment. In this case, there is no need to carry out excavation work and mix a large amount of concrete mortar with your own hands. The piles are tied together with a grillage, on which foam blocks are laid after waterproofing is installed.

Erection of the roof

For a steam room made of foam blocks, an ordinary roof of two slopes with a ridge in the center is well suited.

When choosing the length of the rafter legs, which will be joined at the ridge using an ordinary tongue-and-groove connection, be guided by the width of the bathhouse, the desired slope of the slopes, as well as the climatic features of the area. For example, for regions with a damp climate, roofs with a slope of about 50-60 degrees are better suited. The recommended overlap of the roof overhang on the walls is about 50 cm.

Design of layered rafters for a gable roof

Use staples to tie the rafters together. Fix the beams themselves at a distance of about 1-1.2 m. It is important to choose the right raw materials for arranging the rafter system. Make sure that the material is of high quality, without knots or any kind of defects.

Gable roof

Gable roof

Roof

After installing all the rafter legs, proceed to arranging the sheathing. Make it from high-quality smooth boards. The lathing can be made continuous or sparse. Choose a specific option taking into account the characteristics of the final roofing covering.

Roof of the bathhouse

The sheathing for roofing felt should be double; for slate, a single lathing is suitable. If the roof will be covered with tiles, make the sheathing from beams. Bars with a cross section of 5x5 or 6x6 cm are suitable.

The roof must be insulated with moisture-proof material, insulation and vapor barrier.

Finally, apply the selected finishing material. At this point, focus on your personal preferences and available budget.

Screw piles

Installation of screw piles under a bathhouse made of foam blocks is justified on difficult soils. Sometimes such a foundation is the only alternative to a strip foundation.

The piles are mounted at the corners of the building. If the bath area is large, it is recommended to install additional elements under the walls. Piles are screwed in without the use of mechanized equipment. Such a foundation does not require excavation and mixing (purchase) of concrete mortar. Having finished installing the piles, they are tied with a grillage, which is covered with a layer of waterproofing.

Conclusion

We can say that the price of the material and the relative simplicity of the bathhouse construction technology will allow us to carry out all the necessary construction work independently in a short time.

And so that everything goes in accordance with the technical requirements and recommendations, you will find additional information on this topic in the video presented in this article.