Which foundation is best for a bathhouse??

The stability and longevity of a bathhouse are greatly dependent on the selection of its foundation. In addition to bearing the weight of the building, the foundation aids in withstanding ground movement and moisture. Depending on the type of soil, local climate, and financial constraints, there are multiple options to take into account, each with unique benefits.

A concrete slab is one of the most popular foundation types for bath houses. It offers a strong, level base that is moisture-resistant and able to support large loads. The bathhouse can be more comfortable all year round by controlling the temperature with a well-built concrete slab.

A pier foundation, which is made up of concrete or wooden posts buried in the ground, is another well-liked option. This kind of foundation works well in uneven terrain and permits ventilation beneath the bathhouse, which is advantageous in moist conditions.

In regions where soil is unstable or where water tables are high, a trench or deep strip foundation may be required. In order to avoid shifting and settling as a result of seasonal variations in ground conditions, these foundations entail excavating below the frost line.

The ideal foundation for your bathhouse will ultimately depend on things like the intended use of the structure, soil stability, and local building codes. You can make sure that your bathhouse has a strong foundation for many years to come by carefully weighing these factors and speaking with a licensed builder or engineer.

Types of foundations for a bathhouse

A foundation, also known as a fundamentum in Latin, is a structural component of a building that is subterranean or underwater that balances the weight of the structure itself and any dynamic loads brought on by the movement of water, wind, people, and vehicles. composed of steel, wood, stone, reinforced concrete, or concrete. can be slab, columnar, pile, or strip.

It is evident from the definition that a building’s foundation can vary. Let’s look at each foundation’s benefits and drawbacks to determine which is best for a bathhouse.

Strip foundation

Beneath the building’s load-bearing walls, a strip foundation is a closed, rectangular or trapezoidal shape made of cement-sand mortar reinforced with a metal rod, reinforced concrete blocks, or rubble stone. Transferring the structure’s dynamic and static loads to the ground is its primary purpose. It is extensively utilized in both commercial and residential building. can be combined, prefabricated, and monolithic.

Translating the definition into a more comprehensible language, a strip foundation for a bathhouse is a continuous, "ribbon-shaped" support that is drilled into the ground for a building’s walls that have the same rectangular or trapezoidal cross-section. It extends beneath the building’s interior load-bearing walls in addition to the building’s perimeter. Its width is about ten to fifteen centimeters wider than the wall thickness. Typically, the foundation base is 20–50 cm above the ground.

There are three possible depths for the location: deep, medium, and shallow. To put it another way, building codes require that the foundation be buried up to 20 cm above the soil’s freezing point. However, excavating a trench 20 cm below the fertile soil layer suffices for structures whose walls are composed of lightweight materials. Usually, it’s between 50 and 70 cm. This is a trifle when the soil freezes more than one meter below the surface.

In order to build the foundation, a trench is dug. Simultaneously, about 25 cm down the measured depth of the tape used to fill the sand cushion. It is laid upon or poured upon as the base beneath the walls. Every kind of strip foundation has advantages and disadvantages. We’ll examine them thoroughly. Let’s now examine the advantages and disadvantages of this kind of foundation as a whole.

• versatility – can be used for a bathhouse made of logs and other types of materials;
• high load-bearing capacity;
• resistance to operational loads: moisture, groundwater, soil swelling and vibration from passing vehicles;
• significant operational life, exceeding, in many cases, the durability of the structure itself;

• high labor intensity of the work performed, including earthworks;
• high costs for materials.

Monolithic

A monolithic strip foundation is the most basic kind for a bathhouse. The reinforced concrete is poured into the formwork in the form of a continuous belt. Schematically, it appears as follows:

1. the support area of ​​the future foundation is calculated to determine its thickness;
2. a trench is dug and a sand cushion is poured onto its bottom;
3. formwork is installed (if the soil is strong, it is erected only for the base);
4. a reinforcing frame is laid on bricks or stones;
5. cement-sand mortar is poured.

We’ll talk about the technology in more detail in a different post. Let’s now examine the benefits and drawbacks of this kind of foundation with regard to bathrooms (the pros and cons may vary for other buildings that have a higher weight load).

• versatility – suitable for all types of walls and types of soil, with the exception of peat bogs;
• to calculate all technical characteristics, a calculator and a reference book are enough – there are no complex formulas;
• you can use a non-buried option due to the low weight of the walls if they are made of timber, foam concrete, aerated concrete and other lightweight materials;
• simple pouring technology – the work can be completed by one person, even if a beginner in the construction business has a concrete mixer;
• high rigidity – withstands ground movements with height differences of up to 1.5 m;
• has a large margin of safety, as a result of which the log house or brickwork is destroyed over time, and the base under the walls remains almost in its original form.

• Filling work can only be performed at above-zero temperatures. It is better not to use commercially available plasticizers that allow you to work in cold weather. If absolutely necessary, you can use foundation blocks;
• a large volume of excavation work – significant physical effort will have to be made to complete it;
• high labor intensity – in addition to digging a trench, creating a reinforcing belt and pouring itself takes a lot of time;
• long period for gaining strength – 28-30 days;
• It is necessary to fill in one step – breaks reduce strength.

The view that the option is financially costly is audible. In fact, buying cement and reinforcement is more expensive than, say, installing screw piles. Here, however, all of the work can be done by you alone; there, a portion of the money must be paid to experts. The ultimate cost of installing the "tape" is therefore less.

Blocky

Prefabricated foundation blocks can be used to lay the base more quickly. Similar to the "tape," they can have a trapezoid or rectangular shape. Place a pillow of sand on. A 2 cm thick layer of cement-sand mortar is poured beneath larger structures to block the sand subsidiary of individual blocks when the groundwater rises or the soil freezes. Enough to fill the bathhouse with sand.

Due to a trading margin, concrete blocks can be purchased directly from the manufacturer or through a trading network, where they will cost between 15% and 30% less. A foundation of this type has certain benefits over a monolithic one, and in certain situations, it is required, like when constructing a basement beneath a building (the cost is 2-4 times less, even with the crane and excavator involved). However, the flaws are severe.

• saving time for construction (at least a month);
• work can be carried out almost all year round – frost down to 5 o C is not a hindrance when using additives in cement mortar for sealing joints;
• wide choice in shape, size and composition of the solution – you can always find blocks with the required parameters;
• greater strength is guaranteed by the automatic production process: the production technology and the proportions of components in the solution are controlled;
• high level of frost resistance – achieved during the production process by adding special additives;
• increased resistance to alkaline and acidic soils;
• easy installation. If mistakes are made, you can easily disassemble and reassemble.

• the need to seal joints with cement mortar followed by waterproofing. If the operation is ignored, cold and humidity will begin to penetrate inside the bathhouse, which will negatively affect the wood used;
• a crane and assistants are required – heavy blocks cannot be lifted manually, it is difficult to accurately lay them on the foundation alone, t.To. the crane operator cannot fit the next foundation element to the already laid ones within a centimeter;
• the strength of the base itself is lower compared to a monolithic tape, but sufficient for any type of bath;
• the total cost of installation is quite high due to the use of special equipment.

Combined

Use a combination of pillar and strip foundations if strengthening the foundation is required within a tight construction budget. These bathhouse foundations can be built on unstable soils (clay, loam, peat, fine sand), with a large freezing depth and a high groundwater level (swampy areas). The building’s enormous weight is the only restriction. Thus, floors made of reinforced concrete and brick walls are not included.

The foundation offers benefits and drawbacks.

• fast execution of all types of work;
• low construction costs;
• possibility of construction on unstable soils;
• no special equipment or assistants are required;
• lower volume of excavation work compared to a strip foundation;
• high strength;
• durability;
• resistance to adverse factors: temperature changes, severe frost, high soil humidity.

• not suitable for buildings made of brick, reinforced concrete and stone;
• It takes a long time to gain strength, which is why construction is frozen for at least 28-30 days.

Columnar

A system of pillars buried in the ground in a precise order decided by calculation is called a columnar foundation. provides support for frame-type or lightweight-material buildings, such as summer kitchens, bathhouses, outbuildings, and so forth, that are no taller than two stories. Installed in locations where the foundation is subjected to an increased load, such as the building’s corners, wall intersections, and the box’s exterior, these structures can be made of stone, brick, concrete blocks, asbestos pipes, or brick. All of the pillars are joined to one another by a grillage composed of wood or metal to give the structure rigidity.

Like any other kind of foundation, a columnar foundation for a bathhouse has advantages and disadvantages.

• high construction speed;
• simple technology – all work can be done on your own;
• with proper operation, durability reaches 70 years or more;
• material costs are approximately 2-3 times lower compared to a strip base.

• on unstable soils, pillars may overturn or shift;
• low resistance to large static loads;
• not used in areas with difficult terrain. Complete ban for height differences of more than 1.5 m.

Pile

A pile foundation is the supporting framework for a building or other structure that is composed of free-standing vertical supports that are submerged in the ground and are connected by a grillage that takes the shape of a single, monolithic slab or strip of reinforced concrete. The strapping for lightweight structures is composed of metal profiles or wooden beams. Metal, asbestos pipes, reinforced concrete, or wooden posts can all be used to create piles.

In accordance with the technology employed, the pile foundation may be

• screw – metal pipes are screwed into the ground;
• driven – reinforced concrete piles are driven into the ground;
• bored – reinforcement is lowered into pre-drilled holes in the ground, after which it is filled with cement-sand mortar, forming a reinforced concrete pillar.

The following are benefits and drawbacks of a pile foundation for a bathhouse.

• high resistance to longitudinal and lateral loads;
• ability to work in any atmospheric conditions – frost and rain are not a hindrance;
• installation does not require preliminary preparation of the construction site;
• versatility – used for any type of structure, there are no restrictions on the composition of the soil and the terrain (the only possible type of foundation for walls on a slope or in a fold);
• a large assortment of screw and reinforced concrete piles by size;
• construction time is reduced;
• screw piles in loose soil can be screwed in with 2-4 people;
• large margin of safety;
• durability – service life: metal from 50 years, reinforced concrete from 100 years and above.

• the metal of screw piles is prone to corrosion, which requires purchasing galvanized products or treating the metal with special primers and then painting;
• there is a risk of hitting an obstacle. It is especially unpleasant to receive such a “gift” at the end of work on the corner of a building – you will have to redo everything (screw piles allow you to do this);
• When using special equipment, there are restrictions on working near already constructed buildings.

Slab

For buildings and structures of any kind, a slab foundation is a monolithic, massive reinforced concrete structure in the shape of a slab of high-strength concrete and reinforced frame. Unlike other types of bases, itss does not require the device to be buried deep underground. Pourable soils that are slightly excessive can be used.

The unique feature of the stove is that, in comparison to other structures, it exerts pressure on the soil at a pressure several times lower because of its size. As a result, the building or structure "floats" along with a monolithic base, maintaining the integrity, due to seasonal movements of the soil or its fusion in severe frosts.

A monolithic slab is typically used for baths on drained peats and unstable soils (clay, loam); in a marshy area, it will simply submerge.

• high bearing capacity with properly calculated sizes;
• strength – withstands any load;
• increased resistance to heaving, soil movements, rising groundwater during prolonged rains and during floods;
• simple construction technology;
• versatility – there are no restrictions on the type of buildings and type of soil. The exception is difficult terrain;
• the ability to protect the building from below from groundwater moisture;
• after finishing treatment in the bath, it can serve as the first layer of screed;
• possibility of pouring on bulk soils.

• high cost of work and materials – this is the most expensive type of foundation;
• complex preparatory work: digging a pit, filling a cushion with leveling, installing formwork, laying a reinforcing belt, etc.d.;
• high level of labor intensity when assembling a frame from reinforcing bars and pouring concrete mortar;
• difficulty in organizing water drainage.

Criterias of choice

When building a bathhouse by hand, owners primarily consider the type of soil and walls when selecting a foundation. These two factors are the primary ones. In the first scenario, consideration is given to the hygroscopicity of the wall material and the static load (weight) on the building’s base, which indicates the kind of cut-off waterproofing that is required. Information on how the soil’s composition and homogeneity can support the building’s weight is provided by the second evaluation feature.

Experience demonstrates that two primary criteria are usually sufficient. However, experience has shown that numerous errors were made as a result of failing to take into account additional indicators:

• terrain features. For example, if the height difference is more than 20 cm per 1 m, pouring a strip foundation is possible, but the cost of materials will exceed the installation of screw piles several times;
• depth of soil freezing – must be taken into account when using bricks to build a box;
• ground water level;
• price. For some reason, few people consider how much this or that type of foundation will cost.

Recommendations for selection

The right kind of foundation must be chosen if the building is to last. Sad things happen as a result of mistakes. Ignoring the depth of groundwater, for instance, can result in a strong lateral load on the foundation that it cannot support. Similarly, pouring a "ribbon" on a peat bog causes the building to slowly sink year after year because the peat can no longer support the weight.

So let’s start by thinking about how the kind of bathhouse influences the foundation selection.

Wooden. Any type of foundation can be used for a bathhouse constructed of wood or logs. Here, three factors are primarily considered: the type of soil, the topography, and the labor costs. Hence, a columnar foundation will cost the least to build, but it presents two challenges: first, it cannot be used on slopes, even those with very little slope, and unstable soils; second, it makes it difficult to install floors in the laundry and steam rooms and to arrange water drainage.

Piles are needed in swampy and hilly areas. Screw ones are better because they are less complicated and more affordable. It is also possible to fill a strip base on a challenging terrain, but the family budget will suffer greatly.

Panel-frame. The simplest kind of construction that doesn’t need a strong foundation is a frame-panel bathhouse. Here, choosing between pillars and shallow tape is preferable. But once more, everything is dependent upon the local topography and soil composition. In the event that issues fit one of the specified criteria, such as piles or monolithic slabs (on peat bogs).

Concrete with foam. Foam and gas block construction is as lightweight as a frame-panel bath house. Thus, you must adhere to the advice in the preceding section when constructing a foam block bathhouse foundation.

Expanded concrete made of clay. The heaviest of the above-mentioned building frames is the one composed of expanded clay and concrete. For this reason, it is advised to use a completely buried strip foundation or pile foundation (on slopes, swampy areas).

Block. the largest kind of walls. The columnar base is removed right away. The ideal tape is fully recessed and monolithic. On slopes and in unstable soil, alternative foundation types are primarily utilized.

Table 1 lists the various bath foundation types.

Bath type	Type of foundation
Wooden (log, timber)	Any. Optimally – monolithic shallow tape. For difficult terrain and unstable soil – screw piles.
Frame-panel	Inexpensive – columnar, more reliable shallow belt. Can be made from foundation blocks.
Foam concrete	Another easy build. The conditions are the same as for a frame bath.
Gas silicate	Light walls do not require a strong foundation. A shallow strip or column foundation is suitable.
Expanded clay concrete	Relatively heavy material. The columnar foundation will hold up, but the safety margin is small. Therefore, it is better to fill in a monolithic tape. Use of other types of base – depending on circumstances.
Brick	Creates the largest static load on the base. Therefore, a fully recessed strip foundation is needed. In this case, you can use any of its varieties. The use of other types of foundations depends on the terrain and soil composition.

Depending on the terrain and soil composition, different types of foundations may be used. Another crucial factor is the kind of soil.

Rocky ground. Rocky soil is among the most stable because it doesn’t heave or freeze deeply. That means you don’t need a foundation to build a bathhouse on it. It’s true that you need good cut-off waterproofing in this situation.

When constructing a foundation, you will have to decide between pillars and a shallow monolithic strip. This means that piles cannot be driven, the walls will be significantly raised above the ground thanks to the blocks, the slab will be highly expensive, and it won’t outperform "tape" in terms of technical and operational features.

Sandy ground. The groundwater is deep, the sand is relatively light, and moisture can travel through it easily. Thus, no more than 1 m freezes, even during extremely strong frosts. Experts advise taking all available options for strip foundations and piles in such situations.

It is preferable to forgo the columnar foundation due to the potential for both horizontal and vertical soil displacement during periods of heavy precipitation. It’s like shooting sparrows from a cannon, a solid slab on the sand.

Soils made of clay. Among unstable soil types, clay comes in second (peat bog is first). Its high water content gives it low strength (it turns to mush after rain), heaving tendency, and large freezing depth.

Furthermore, a lot of subsidence rocks are found in clay lenses, and when pressure builds up on the ground, this can cause the soil beneath the bathhouse building to sink. Consequently, screw piles are advised as long as they pierce through the clay layer and arrive at a solid pad, a block strip buried deeply, or a monolithic slab, whose operational and technical qualities allow clay soils to be neutralized.

Soils with peat. Because the peat is porous and light, it lacks the necessary strength to withstand static loads and flows unevenly. Consequently, you have to decide between buried screw piles and a monolithic concrete slab.

There are a few things to consider when selecting the ideal bathhouse foundation. Important factors to take into account include the type of soil, the climate in the area, and the bathhouse’s dimensions and weight. Your bathhouse’s longevity and structural integrity depend on having a firm and stable foundation that won’t settle or move over time. While pile foundations are best suited for unstable soils, options like concrete slab foundations provide strength and moisture resistance. You can choose the best foundation to sustain your bathhouse for many years to come by carefully weighing these variables and seeking professional advice.

Can a bathhouse be without a foundation

Julian Semenov once wrote something intriguing that read, "If not, but really want, then you can." Additionally, you are free to forgo a base beneath the walls in a bath that does not have a foundation. Then again, there are a lot of surprises ahead of you.

1. Direct contact of the log house, aerated concrete, frame or brick walls with soil, dew, rain waters leads to the rapid destruction of the building. No wonder any foundation has been used for centuries for centuries.
2. There are difficulties with a drain of water and floor ventilation.
3. There are risks of wall deformation when the soil swells during freezing or moves when groundwater rises.

Rocky ground is the one exception. However, building walls right on the ground is not advised in this situation. Good shut-off waterproofing is required.

In conclusion, if the owners intend to use the bathhouse for many years, a foundation must be built underneath it.

Foundation Type	Advantages
Poured Concrete	Strong and durable, resistant to moisture and pests.
Concrete Blocks	Cost-effective, easier to construct than poured concrete.

The stability and longevity of your bathhouse greatly depend on the foundation you choose. Your choice of foundation type should take into account a number of variables, including the size of your building, your budget, and the state of the soil.

A concrete strip foundation is a solid option if your bathhouse is situated on level ground with adequate load bearing capacity. Build-wise, it’s reasonably priced and offers strong support all the way around the structure.

An reinforced concrete slab foundation may be more appropriate in areas where the soil is unstable or has low load-bearing capacity. By distributing the weight evenly over a broader area, this kind of foundation lowers the chance of settling or structural damage over time.

Frost-heave can be an issue for bathhouses situated in regions with exceptionally cold winters. A frost-protected shallow foundation (FPSF) may be useful in these circumstances. Insulation is incorporated into this design to keep frost from getting below the foundation, which lowers the possibility of heaving and cracking.

The ideal bathhouse foundation will ultimately depend on a thorough evaluation of your unique site conditions, the local climate, and your financial limitations. A competent engineer or contractor can offer advice on foundation selection that will guarantee your bathhouse has the longevity and support it needs over time.

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