How high should the basement floor be? Height of foundation above ground level (required balance)

Before starting the construction of any building, be it a wooden, brick, stone, block house or, for example, a barn, a bathhouse or any other outbuilding, it is necessary to calculate, design, draw, and only then get to work. Of course, if you have engineering, architectural or design skills, then this will not be difficult. And if you do not have such experience, then all calculations must be carried out carefully and very carefully, taking into account important features and possible errors. And one of the first questions that arises in this case is the choice of a house above ground. The height of the foundation for a wooden and any other house should be selected from the point of view established provisions and standards. This is the only way to build a reliable and most stable structure.

Foundation for a house and its height: goals and purpose

The foundation for a house performs a very important function. It is the basis of a wooden, brick and any other house or utility structure. It is this that bears the entire main load during operation. The foundation for a house connects what should be underground during construction and the upper, above-ground part of the building. That is why it should be correct, and higher does not mean better. Usually it's the other way around.

The foundation for the house provides protection for the walls from negative impact moisture. It can simultaneously perform the functions of a plinth. Such a monolithic design is much better than 2 separate ones.

The height of the foundation for a wooden or any other house is also important because during operation a house or other economic structure can undergo significant shrinkage. The foundation, in turn, can prevent the destruction of a house, especially a wooden one.

For wooden house A columnar foundation works very well. It is designed specifically to ensure that the lower part of the structure does not come into contact with the soil and the soil does not have a negative impact on the building.

It turns out that to calculate the minimum height of the foundation of a house above ground level, the following factors must be taken into account:

1. The material from which the house is built.
2. Features and type of soil.
3. Does the project include the absence or presence of a basement?
4. What is the level of snow cover in the winter season.
5. Precipitation at other times of the year.
6. Availability of groundwater.
7. Soil freezing depth level.
8. And much more.

According to GOSTs and SNiPs, the height of the foundation for a house above ground level must be at least 20 cm. However, this is the minimum. In practice, this value is much higher. That is, the minimum is 35-40 cm. If the foundation for the house and the building itself are built on clay soil, then the height can reach 80-90 cm. For sandy soils, 50 cm is usually enough. When calculating the height of the foundation for a house, it is necessary to take into account the type of supporting structure .

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Strip foundation and its height

This is a relatively inexpensive and very popular type of base. Its only drawback, however very significant, is the dependence of construction time on the time of year, because... The tape cannot be left during the period of soil freezing, i.e. in winter. In this case, it is necessarily insulated with heat-insulating materials: sawdust, expanded clay, slag wool. It is best to try to avoid such freezing at all. And you can’t start building a belt on frozen ground.

The height of such a foundation for a house directly depends on the type of soil, soil, the possibility of freezing and the level groundwater. The optimal height is considered to be about 0.8-1 m, however, on rocky surfaces, the depth may be completely absent, which is why the height can be reduced. If there is a need for greater depth, then in order to save the main material, be it slag, rubble stone or brick, sand cushions are used. The height of such pillows under the foundation cannot and should not exceed 45-50% of the height of the very foundation of the house.

Strip foundations are used when building a house with a basement or when the walls of the future structure are very heavy. This type of foundation is also used when building a house without a basement heaving soil. Moreover, the height of the base in this case will be relatively small. Where the soil is heaving and freezes deeply, the construction of such a foundation is not financially profitable.

Pieces of bricks, gravel, rubble, etc. are suitable for filling. The bottom of the foundation pit must be thoroughly compacted. The filler is laid in layers.

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The height of the strip foundation depending on the construction method

A strip foundation for a house is a wall that is evenly loaded with the walls being built above it. This foundation has proven itself well in the construction of heavy buildings. When constructing lightweight structures, for example, a wooden house, it is practically not used, because in most cases this is not profitable.

Belt structures are divided into monolithic and prefabricated. To build such a foundation, concrete and reinforced concrete are used. Reinforced concrete foundation is characterized by higher strength, because includes a reinforcement cage. During construction multi-storey buildings Prefabricated reinforcement elements are almost always used, usually reinforced concrete slabs. However, if the house is built on heaving soil, then the construction of a prefabricated foundation will be extremely dangerous, because The connections of the blocks are fragile, and when the ground freezes, such a foundation can shift quite significantly. In such cases, it is more advisable to use a monolithic structure. Its frame consists of reinforcement tied with wire or connected by welding.

As already mentioned, the top of the strip foundation for a house simultaneously serves as a plinth. In order to protect the base from the effects of surface water and rain, it is necessary to make a blind area immediately after construction.

There are 2 ways to build such a foundation. In the first method, a trench is dug in the ground, the side walls of which are lined with roofing felt. After that, sand and gravel are poured to the bottom and concrete is poured.

The second method is used when building a house with a large basement. At the same time, a large pit is prepared, formwork is arranged and concrete solution is poured into it. When using this method, the height of the strip base is 30 cm above the ground surface. Be sure to provide good hydro- and vapor barrier. The part of the foundation protruding above the ground can be made of brickwork. The outside is insulated.

The strength and durability of the house depends on how well the construction is done. It is better to initially build with high quality and in compliance with technology than to repair in the future, spending a lot of money on it.

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Columnar foundation and its height

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Foundation on screw piles and its height

Screw piles are also quite often used in construction. All thanks to the fact that such a foundation for a house can be installed at any time of the year, despite weather conditions and freezing. This design is strong, can withstand fairly heavy loads, and does not respond to the quality and properties of the soil and the presence of groundwater. Installing piles takes little effort and time. The construction of such a foundation is impossible only on stony and rocky rocks.

So, for a wooden house, piles 2.5 m high with an external diameter of 108 mm and a steel thickness of 4 mm should be used. When building on stilts, many important factors must be taken into account, which determine the final cost of production and installation. Therefore, it is not recommended to perform the calculation yourself without the appropriate skills. Moreover, it is better not to try to install a foundation on screw piles if you do not know how to do it correctly. Any inaccuracy will adversely affect the durability and reliability of a wooden house and put the health and lives of residents at risk.

One of the most common blunders is unscrewing the pile to adjust the height. The thing is that the high capacity of the pile is ensured by screwing, in which the interturn spaces of the soil are not loosened, but rather compacted under the influence of the pile blade. Therefore, when the pile is screwed in and out again, a layer of loose earth is formed under it, as a result it can sink to the height of the screw-out under the influence of the load.

Another gross mistake is screwing a pile into a hole dug in advance for some purpose. To ensure sufficient load-bearing capacity, the installation depth of the pile in the bedrock (main) soil must be at least 60-80 cm. This is a conditional value that can vary upward and depends on specific conditions. Eg, screw pile 250 cm long to make a foundation must be screwed into the ground to a depth of at least 150 cm. If the top layer of soil is unstable (peat), then the screw pile is extended to the required length and then screwed until this unstable soil is passed through. That is, the pile must have horizontal stability.

At the design stage, individual foundation parameters are selected in accordance with the type of building: the area of ​​the base, on which the width of the foundation and the height of the foundation above the ground depend.

The optimal height of the basement part, elevated above the ground, is 30–40 cm. If the house has an underground floor, the height can reach 1.5–2 m.

To determine the height of the base, you need to pay attention to atmospheric phenomena in the area:

• Temperature indoors and outdoors in winter;
• Snow level;
• Abundance of precipitation;
• Possibility of flooding;
• Ground water level.

The above-ground part of the foundation is the most susceptible to destruction under the influence of atmospheric phenomena.

Why is this part of the foundation necessary? Let's take a closer look:

Based on all these indicators, we can conclude that the optimal height above ground level is 350–400 mm. If the foundation is located high above the ground, this is good in all respects. You also need to take into account the heat and waterproofing of the lower part of the foundation. After all, these indicators will not only preserve your foundation, but also reduce heat losses.

Balancing between necessity and redundancy

The customer makes the main contribution of money in building the foundation. If you choose a special area and take into account all the nuances, the foundation will be a durable platform for the entire house.

Height pile foundation above the ground is used in conjunction with the area of ​​the sole and their width. And it depends on the type of construction of the structure.

Finishing the above-ground part with metal siding

Basement cladding with metal siding has become the most popular.

Siding finishing principle:

Types of foundation. Relation to ground level

Dependence of the height of the foundation above the ground:

From all these points we can conclude that if all conditions are met, it is important to determine the height of the foundation.

There are 4 types of foundation:

• Tape
• Columnar
• Monolithic
• Pile

Strip foundation - This is a reinforced concrete strip over the entire area of ​​the building. It is used in the construction of private houses. Thanks to the simple design, you can make a warm underground. Strip foundations are used in the construction of heavy walls. The optimal height is 2 m.

Columnar foundation used in light buildings one-story houses. Used only on stationary soils. Cannot be used on swollen soils. Easy to make, can be used on slopes. Service life 50 years. With this type of foundation it is impossible to create a basement. A columnar foundation can be built from brick, asbestos pipes, or wood. Pole height 1.5 m.

Monolithic foundation - This reinforced foundation. Easy to build, does not require special equipment. Big square distributes the load on the ground. The monolithic foundation is reliable and has a long service life. This foundation is made of reinforced concrete and has a height of 300 mm. Monolithic foundations are built on all types of soils. The indicator for this type of foundation is 1.2 m.

Pile foundation used in all types of constructions. It has low cost, high bearing capacity. Used on all types of soils, except rocky ones. If the structure is uneven, it may shrink. Its service life is 100 years. The height of the pile foundation is 2–2.2 m.

DIY arched canopy

An arched canopy is an indispensable extension on the territory of a dacha, country house or cottage. The most commonly used material now is polycarbonate. It is lightweight, durable, fireproof, and much stronger than plastic.

The first step is to concrete the base for the posts, then install the arches on the posts. The structure is fixed simultaneously on opposite sides to avoid distortions. We connect the trusses and racks, and connect the arches with the guides. Holes are drilled into the polycarbonate at a distance of no more than 30 cm and rubber gaskets are secured. Connect the frame and polycarbonate. Apply sealant to the joints once the canopy has been installed.

Optimal foundation height for a wooden house

The optimal foundation height for a wooden house depends on a number of factors:

• Depending on the climatic conditions of the area. Level of permafrost and water layers.
• From geological conditions.
• From the selected type.
• From the load. Seasonal or year-round use.

Rounded log or laminated veneer lumber. What's better?

The disadvantage of rounded logs is their shrinkage after the construction period. Over time, such houses may become askew. Glued laminated timber retains its shape for many years and the house does not lose its external and internal beauty. The strength of laminated veneer lumber depends on its manufacturing technology.

A rounded log is made from solid wood, by mechanical processing, and has a rounded shape. Glued laminated timber is made from high quality boards. Coniferous trees are used for its production. The boards are impregnated with a special solution and trimmed. After all this, the boards are glued together so that the wood fibers match. Therefore, laminated veneer lumber is better for your home.

Individual heating of a house made of rounded logs.

The most common heating method in a rounded house is a gas boiler. Fuel is much cheaper, high efficiency.

Also chosen as heating:

1. Electric wall or floor boilers.
2. Coal or wood stoves.
3. Wood-burning, electric fireplaces

Repairing a house made of rounded logs: disadvantages

• Must pass from the start of construction to its finishing works 6 months. High percent wood shrinkage 10-12%. If you do not wait until the end of the active phase, you will end up with through cracks in the walls and a skewed frame.
• After 2 years, the second caulking procedure is repeated.
• Wooden walls require preventive maintenance and repairs.

You can build your own house, but we recommend that you contact quality specialists who will perform any type of work. With us you save up to 500,000 rubles.

Before starting construction, any building structure, it is necessary to develop a competent and detailed project for the future structure.

Its mandatory component will be data regarding the characteristics of the base.

The project must contain information about the depth of the underground part, the overall dimensions of the base, and the materials used.

The height of the foundation above ground level is also an important parameter. Many developers are trying to save money on it.

A significant portion of the capital is spent on the construction of the foundation. total amount construction. Each individual developer strives to reduce these costs as much as possible.

And if, by calculating the width and depth of the base, we receive mandatory parameters that must be followed when carrying out construction work.

When constructing the above-ground part, you can use more affordable building materials and vary the height within certain limits.

What affects the height of the foundation

It should be understood that the extent to which the structure will be exposed to external climatic influences: temperature fluctuations and humidity depends on the above-ground part of the foundation.

To solve the issue related to its height, it is necessary to understand why the base should be raised above the ground level:

• The above-ground part serves as a basement covering. It is clear that a one-piece structure will have better performance than a structure consisting of two parts;
• The walls of the house receive additional protection from moisture. Even with a blind area, they are constantly moistened. Creating an intermediate layer reduces this influence. The height of the foundation above the ground should not be less than 200 mm;
• Sometimes this parameter is affected by the presence of a basement. Then this value is determined based on the design documentation data;
• For pile and columnar foundations level above ground foundation also cannot be less than 200 mm. This is necessary so that the heaving soil does not affect the building structure. If there is a slope, this distance can be greater;
• When making calculations, it should be taken into account that the house may shrink due to the characteristics of the soil and the impact of pressure from the building structure;
• Sometimes, by increasing the height of the foundation above ground level, it is possible to avoid the destruction of the walls of the structure. This is especially true for wooden buildings, for example, bathhouses. In such situations, at the stage of design work provide for a high base, or use other building materials when constructing the base.

How do the parameters of the foundation compare?

As an example, let’s look at how the parameters of the foundation are calculated when building an individual house.

Practice shows that the ratio of the height of the above-ground base to the width is 1:4.

The structure of the classic does not imply the presence of a base. As a rule, the height of the foundation above ground level does not exceed the underground part, but the opposite option occurs quite often.

If the soil at the construction site has standard characteristics, usually the height and depth are the same and do not exceed 0.5 m.

Building up the base

Both the foundation and plinth structures have four different surfaces - top, bottom, interior and exterior. Each one must have an absolutely even surface.

An uneven base can later lead to deformation of everything. building structure. How to remove unevenness and, if necessary, increase the height of the foundation?

Most often, raising the base is done using solid bricks. It is used to strengthen and increase the base part to the desired size. Reinforced mesh is used to strengthen the masonry.

When tying brickwork use cement mortar. When constructing frame or wooden buildings, solid bricks are used to strengthen the foundation. Cinder block houses are reinforced with concrete.

How to level the base

The following methods are used to level the base:

• Correction of significant defects formed on the foundation covering is carried out by manufacturing a new formwork structure and pouring concrete mortar;
• In case of small irregularities, the foundation base is covered with bricks from the outside;
• Instead, you can use a chain-link mesh. First, it must be securely fixed and then covered with a layer of plaster;
• The existence of small irregularities located on the inner surface can be neglected. They will not be noticeable under a layer of thermal insulation coating;
• To obtain a perfectly flat top surface, it is most convenient to use brickwork.

Level of the above-ground part of the base for a wooden structure

For a wooden structure, having a sufficient foundation height is especially important. This will prevent the process of rotting of the lower part of the structure.

To make such a base, brick, concrete, metal or wood can be used. It is imperative to carry out high-quality waterproofing using coating or roll materials.

When choosing the optimal height of the plinth, it is necessary to take into account the climatic features of the area in which the building site is located.

In standard situations, the level of the above-ground part should be 10 cm higher than the height of the snow cover.

The foundation must be protected from moisture not only from the bottom, but also from the sides. For this you can use ceramic tiles or clinker.

If the foundation of the house is located high enough, its thermal insulation properties will improve and the operating time will increase.

conclusions

With a higher foundation location, the lower part of the building structure is better preserved. The optimal level above the ground is 0.4 m.

You should remember the need to carry out hydro- and thermal insulation work. This will protect the foundation from moisture and prevent destruction of the reinforcement frame.

The video shows which foundation height above ground level is best to choose:

One of the most important technical characteristics of any modern building is the height of the foundation above the ground. This indicator is included in construction project still at the stage of its development.

The value of this parameter ultimately depends on the class of the structure being built and is used in construction technologies simultaneously with such technical characteristics, like sole area and width.

Choosing the optimal solution

Taking into account the fact that preparing the foundation is associated with significant costs, it is quite understandable that the developer will want to optimize the main parameters of the structure being built. The height of the part protruding above the ground is the only adjustable value, the value of which you can choose at your discretion (with a fixed depth and width).

Everything that is above the so-called zero mark can be classified as the above-ground part of the building, for the preparation of which materials of a cheaper price category can be used.

Purpose of the above-ground part of the foundation

In the most general case, the above-ground part of the base is a connecting link in the transition area from the ground to the external air environment. We also note that during the operation of the building, this part of the foundation is subject to the maximum destructive effects of climatic factors, for which reason it is necessary to explain in more detail what it is intended for:

• First of all, this part plays the role of a plinth, thanks to which such a monolithic structure is much preferable to the combination of “foundation plus plinth”.
• This part of the building represents a natural protection against the penetration of moisture into the walls of the building, implemented by raising the “foundation-wall” boundary as high as possible (up to 200 millimeters for strip foundations).

• Sometimes an elevation above the ground is used to create a basement in a building. In such a situation, the height is selected taking into account the data included in the construction project.
• For columnar and pile type foundations, this parameter is the same 200 millimeters. As in the situation with a strip foundation, such an elevation eliminates the influence of the soil on the building itself. This indicator may be changed in case of difficult terrain in the development area.
• When choosing an elevation indicator, you should take into account the potential shrinkage of the house, the value of which depends on the quality of the soil and the number of storeys of the structure.
• By increasing this indicator, it is sometimes possible to prevent the destruction of the walls of a building being built (a bathhouse, for example). For buildings of this type, its value is usually chosen around 500 mm. In some cases, the base of the structure can be built on from a material of one type or another.

Conclusion

Thus, to determine the required height of the foundation above the ground, you should simply add at least 200 mm to its protruding part. Taking into account the average annual thickness of snow cover in a particular region, this figure can vary within 100 mm.

Experts believe that the more this part rises above the ground, the better (360–400 millimeters are considered the optimal value).

In addition, you should not forget about waterproofing, through which you can eliminate the possibility of moisture penetrating the elements load-bearing structure buildings.

The foundation is the basis of any wooden structure. It takes on the main load during operation and protects the house from the negative effects of groundwater.

FACTORS AFFECTING THE SIZE OF THE FOUNDATION

The foundation consists of a basement and an underground part, the dimensions of which depend on several factors:

1. Type of soil and its changes in the autumn-spring period. Foundations laid on capricious sandy or marshy soils have special requirements.

2. Level of soil freezing and availability of groundwater. The base must lie below these points and requires high-quality waterproofing and insulation.

3. Weight and number of storeys of a wooden house.

4. Tasks of the basement and plinth.

VALUE OF BASE

The above-ground part of the foundation performs several functions:

· Prevents internal floors from getting wet;

· Compensates for soil shrinkage;

· Protects the cladding of the house from contamination;

· Promotes high-quality ventilation of the underground;

· Increases the thermal insulation characteristics of the building;

· Considered an architectural decoration.

The height of the plinth plays a huge role especially for wooden houses, since rotting of the lower rows complicates the repair work and reduces the service life of the building.

The standard height is approximately 30-40 cm. But experts advise equipping the ground part of the foundation of a wooden house to a height of 60-80 cm. On clay soils this value can reach 80-90 cm, and on sandy soils 50 cm is enough.

TAPE BASE

A common foundation option for a wooden house. The monolithic structure allows you to equip usable area plinth at moderate construction costs.

In areas with severe winters and soil freezing to an impressive depth, the underground part of the strip foundation can reach 1.5 meters. The height of the base depends on several conditions (for example, the presence of a boiler room or basement). The furnace room requires special responsibility, so the height of the above-ground part is characterized by safe use and correct placement of equipment.

Regardless of the quality of the soil and terrain conditions, it is recommended to build plinths of sufficient height for wooden buildings. Wood is a very capricious material, therefore, the higher the house is raised above the ground, the longer it will last.

The optimal size of a strip foundation is about two meters, which means that the ground part is 50 cm.

CLASSIFICATION OF THE PINTER FOR STRIP FOUNDATION

The above-ground part is divided into two types:

1. Monolithic. The base is made in the form of a continuous (indivisible) concrete sheet.

2. Masonry. First, the lower part of the foundation is poured (to the soil level), and then the base is laid out (made of brick or other material). A less reliable option that requires additional cladding.

PLATE BASE

According to building regulations, monolithic slab should rise above the ground surface by at least 20 cm. But for regions with unregulated snow cover levels, this parameter should be increased to 40 cm.

A monolithic slab is considered the most reliable type of foundation. Its underground part should be buried below the soil freezing level. The strength of the slab does not depend on potential ground movements, but in case of probable seismic shifts, its height must be increased. The total thickness of the foundation depends on the weight of the wooden house, its number of storeys, area and type of soil.

PILE FOUNDATION

Arranging a plinth on a pile foundation is accompanied by certain difficulties. Its dimensions depend on the height of the ground section of the piles. The base can be hinged or made on a tape.

The design of the hinged version consists of a wooden or iron sheathing fixed around the entire perimeter. After arrangement, it must be sheathed with any facing material.

The second option is more complex and expensive. Masonry is carried out on strip foundation. Its main advantage is the fairly high quality of thermal insulation.

BASE CONSTRUCTION

The ground section of the foundation can be made in several options:

· Sunken. An economical option for a plinth, typical for walls with a small thickness. Allows you to hide the protrusion using waterproofing material or a small layer of soil.

· Speaker. Requires more building materials. Provides reliable protection for a wooden house from cold air, but requires high-quality waterproofing and drainage.

· The base is flush with the wall. The most unfortunate and rarely used solution, requiring constant monitoring of the cut of the waterproofing layer.

MATERIALS

To build the above-ground part of the foundation, it is necessary to use durable materials - concrete, brick, different kinds stone In most cases, the base of a wooden house requires the installation of an armored belt. The number and thickness of reinforcing bars depend on the design of the building.

· For wooden houses, a base made of monolithic concrete is best suited. Its arrangement requires the installation of formwork and reinforcement cage.

· For a structure made of solid (not gas silicate!) brick, it is necessary to take material with high frost resistance.

· Using concrete blocks requires special skill. Between them there will certainly remain various voids, which must later be filled with cement mixture.

HEAT AND WATER INSULATION

High-quality heat and waterproofing are mandatory steps for arranging the basement of a wooden house. Insulation must be done with porous materials with minimal water absorption. For waterproofing, bitumen mastics or roll materials are suitable.

The height of the base and the features of its arrangement depend on many parameters. But under any conditions, the minimum level of the ground part should not be less than 20 cm. This will help protect the house from flooding and increase the “life” of the lower wooden crowns.