Minimum height of foundation above ground and total height. Base height - design options Is it necessary to raise the foundation above the ground

How high should the base of the house be and what does this indicator affect? How to determine the optimal plinth height for a wooden house?

Many owners, when building a house with their own hands, doubt whether they should pay attention to the height of the base. Some even believe that it is enough to simply build the foundation to ground level, after which the walls can be erected.

In reality, this is not enough. It should be understood that to prevent the occurrence of capillary processes in them. The fact is that the humidity of the lower part of the house and the upper part can differ significantly due to the proximity of groundwater, snow melting and many other factors.

As a result, low-lying walls made of wood or porous materials will get wet, which will not only worsen their thermal insulation qualities, but also reduce the service life of the entire structure. The high base of the house will prevent this process.

Standard height

The optimal height of the basement of a residential building is 35-40 cm. For wooden buildings, it is better to make it higher - 50 - 90 cm. For buildings with basement floors, this value can reach two meters.

When determining the altitude, it is necessary to take into account climatic conditions, such as the average temperature during the heating season, the amount of snow, etc.

Main functions

Now let’s look at all the functions that the above-ground part of the base of the house performs in order to understand what role its height plays:

Note!
The height of the base of a wooden house is especially important, since rotting of the lower crown is an eternal problem for houses made of logs and timber.
Therefore, it is necessary to build a foundation from damp-resistant materials.

The only disadvantage of a high base is that the cost of construction increases. Therefore, many developers, for reasons of economy, try to reduce it. However, such savings are not justified.

Types of socles

Depending on the types of foundation, methods for constructing a plinth may vary.

Let's consider its design on two types of base:

Tape;
Swine.

On tape

In the first case, the following types of base are usually made:

Monolithic - the above-ground and underground parts of the foundation are monolithic concrete walls. It is erected simultaneously with the pouring of the foundation.
In the form of masonry - in this case, the foundation is erected to the ground level, after which masonry is made of brick or other material. This structure is less protected compared to a monolithic wall, and therefore requires additional finishing.

On pile

As a rule, the greatest difficulty during construction is the construction of a plinth on a pile foundation. Its height is determined by the above-ground part of the piles.

Depending on the type of device, such a base comes in two types:

Hinged structure;
On a shallow strip foundation.

The easiest and cheapest way is to make the first type of foundation. It is based on a sheathing, which is attached to piles along the perimeter of the building. It can be made from wooden beams or metal elements. Next, the sheathing is sheathed with facing material, for example.

Note!
The height of the columnar foundation must be at least 20 cm to prevent the possible impact of heaving soil on the building.

The second type of foundation is more difficult to manufacture and costly. Its principle is to arrange a strip foundation around the perimeter of the room, on top of which masonry is carried out. The advantages of this design include the fact that it insulates the structure much better.

In the photo - the base is covered with siding

Finishing the above-ground part of the base

Despite the fact that the high base itself performs a protective function, to make the structure more durable, it needs to be finished. This will prevent the negative effects of precipitation and, moreover, will make the structure more beautiful. As an example, consider cladding with basement siding, as the most popular material.

Brief installation instructions are as follows:

Work begins with preparing the walls - it is necessary to eliminate unevenness. If the geometry of the walls is severely disturbed, then it is more advisable to perform lathing than to level them.
Then the starting strip is mounted, which is installed strictly horizontally, at a height of 40 mm above the lower point of the future cladding.
Then the panel is installed in the guide bar and fixed with self-tapping screws.
Next, a second panel is inserted and moved to the previous one. It is necessary to leave a small gap at the joints, which will allow the material to expand freely with temperature changes.
Then the entire remaining area is sheathed in the same way.
At the end of the work on the panels, a finishing strip is installed.

Advice!
To insulate the building, thermal insulation material can be laid under the cladding.

Now the lower part of the house is not afraid of any precipitation or other atmospheric phenomena.

Conclusion

From all of the above it follows that the higher the base, the less problems there will be in the future with heat leakage and the safety of the walls of the house. However, the height should be reasonable as it increases the cost of the structure. At the same time, it is necessary to take care of protecting the base itself by finishing it with reliable material.

For more information on this topic, watch the video in this article.

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 the construction project 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 as 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 into the elements of the supporting structure of the building.

Having acquired a plot of land and started building a house, not all private developers know which parts of the facade should pay special attention to. There are a lot of nuances in the design and construction of the basement of a building, without taking these into account, the owner faces many problems during operation. The main function of the basement area of the building is to protect the facade from direct contact with the soil.

The base compensates for shrinkage under the weight of the building.
Protects the insulation of basement floors from extraneous influences.
Increases thermal insulation capabilities.
Provides high-quality ventilation.
Protects the façade from contamination.
Creates a complete look for your home while maintaining its aesthetic appearance.

Determine the height of the basement in your home

Types of socles

To perform the assigned functions, the facade of the building must have a certain height. The external wall must rise above the ground level, be strong, and have high performance data. The height depends on the soil, the foundation of the plinth and the clearly designed type of facade. There are several types of sockets:

Sunken. Used for buildings with wide walls. There is an external wall inside the façade.
Speaker. The base, made in a certain plane, is pushed forward. This solution is ideal for buildings with an existing ground floor and not too wide walls.
Uniform. This part of the building smoothly transitions into the facade. That is, both the lower and upper parts are located in the same plane.

Each type has unique features that determine the height, external and quality data of the basement floor.

In this video we will look at the difference between a high and low base:

Finishing the above-ground part of the plinth with metal siding

The plinth is of optimal height and ideally copes with the protective functions assigned to it. To ensure that the structure is in good condition for a long time, during the construction period the above-ground part of the foundation is constructed only from high-quality materials. The measures taken prevent possible damage and create an attractive appearance for the facade of the house.

A striking example of modern house construction is base metal siding. The facing material is quite in demand, popular, and has a large number of positive reviews. The workflow goes like this:

Finishing begins with cleaning the surface. All defects and irregularities present on the rough wall are removed using high-quality lathing.
Install the horizontal guide rail.
The siding plate is inserted into the lath and secured with self-tapping screws.
The next sheet is installed, slightly moving it towards the previous one. Minimal gaps are left at the joints for expansion during the hot season.
Next, the entire height and width of the base of the house is finished in the same way.

Base height

Many operational aspects depend on the height of the barrier wall. Just like the height itself depends on the design of the building, the type of foundation, the quality of the soil, and the presence of a basement in the structure. Existing building codes provide certain requirements. Designers, using the manual, calculate the minimum or maximum height of the base.

Standard height

The standard height of the plinth is calculated from the ground according to the standards and is 30-40 cm. For wooden buildings, it is erected up to 80 cm. If there is a ground floor in the building, the indicators reach from 1.5 to 2 m. When determining the height of the plinth above the ground, take into account:

location of the area;
climatic conditions;
amount of possible precipitation and snow;
possible flooding;
ground water level;
air temperature, both indoors and outdoors.

Only specialists are able to correctly and accurately calculate norms, standards, requirements and requests. Developers, by turning to them, avoid serious costs for refurbishing the building.

Optimal height

When drawing up a project for a country house, designers try to rationally plan the space, and one of the important decisions is additional storeys. A basement floor in a private building is necessary. It can be used as a boiler room, pantry, or storage for winter supplies. If desired, you can equip living and play areas.

If you take into account all the additional costs of the foundation, the result is that the optimal length of the basement wall is cheaper than building a second floor. The general parameters of the basement are 2.5 m. The ceiling is about 2 m. The depth of the floor in the ground is no more than the size of the basement. This part of the building, like the basement, completely depends on the intended purpose of the underground premises.

What does the height of the base affect?

The developer always has the right to choose, and he decides independently what the parameters of the basement wall should be. But the security of the building materials used for construction and the condition of the interior depend on this, at first glance, not very important part of the house.

The height of the base depends on the amount of possible precipitation

The basement part of the building is assigned protective functions. It protects the structure from frost and dampness. The space between the wall and finishing materials is filled with a layer of thermal insulation. It is enough to make a base of the correct length, lay it out with modern facing materials, install a drainage system and a drainage system.

Installing all the necessary additions will save the building from many destructive factors. The structure will be protected from the effects of unpredictable weather conditions and humidity. Flooding of premises located below ground level will be excluded.

What height is best to make a plinth?

Precisely calculated standards for the height of the basement wall exist, but each site owner has the right to make their own choice. When deciding on construction, you should remember that this is the above-ground part of the base of the building. The higher its height, the more difficult it is for extraneous factors to penetrate into residential premises. Also, the basement walls are separated from the walls of the first floor by waterproofing.

The ground parts of the building periodically get wet from snow and rain. The thermal insulation layer is damaged, internal destructive processes occur, which significantly shorten the operating period. Watching such metamorphoses, the owners are perplexed as to why the house loses its aesthetics and beauty. Sometimes the answer is obvious - the basement structure is too small.

Options for foundations according to the height of the base in a private house

The choice of the height of the basement depends entirely on the building material from which the house is being built and the type of foundation chosen. The location of groundwater and the proximity of the building to the highway are also taken into account. And, of course, the appearance. A building with a high fence looks much more interesting and respectable.

In the construction of private country houses, strip foundations are often used. On this basis, the base part is installed in various ways:

Masonry. The foundation is laid to ground level. Next, install masonry made of brick or other raw materials. The design does not have good thermal data. Additionally, insulation, finishing, and cladding are carried out.
Monolith. The base is made of concrete. In this case, the basement installation is connected to the pouring of the foundation.
Pile foundation. The height and thickness of the plinth is determined from the part of the piles located above the ground surface. On this basis, the basement structure is suspended.

Conclusion

Drawing conclusions, we can come to the conclusion: higher performance characteristics are obtained by high plinth fencing.

The height of the base is one of the parameters that is of great importance when building a house. This is the lower part of the building, erected on a foundation and performing important functions related to retaining heat indoors. The plinth is necessary in order to protect the walls from the effects of groundwater; it prevents the formation of fungus and mold on the walls, and increases the resistance of the building to low temperatures. Thanks to the presence of the base, the heat exchange between the interior and the street increases.

In order for this part of the house to meet all the requirements and contribute to the solution of the assigned tasks, it is necessary during construction not only to choose high-quality and reliable material, but also to take into account the height of the basement being built.

How to determine the height of the plinth

One of the types of base is recessed

The effectiveness of the protective functions performed by the base of a house directly depends on its height and type:

The protruding base requires additional finishing and the construction of a canopy that protects the structure from precipitation and moisture accumulation. It becomes a decoration of the facade of any building.
The sinking one is the most durable. In this option, the junction of the base and the walls of the house is completely protected from moisture, which guarantees increased safety of the foundation and protection of the waterproofing layer. When constructing this type, there is no need to construct mandatory water outlets.
Level with the wall. The least popular type of base. It requires the construction of a canopy, and when additional finishing is carried out it becomes protruding.

The choice of the height of the basement being built is influenced by the type of foundation, the depth of groundwater, and climatic conditions in the area where construction is taking place. In addition, the presence of a basement floor (basement) is important.

When starting work on the construction of a basement, it is worth considering that the higher it is, the less likely it is that the interior will suffer from moisture penetration. Construction begins directly from the foundation of the house, and the joints with the walls of the building require proper organization of waterproofing, preventing possible penetration of moisture through the capillaries of the porous material into the walls of the building.

The base is flush with the wall

The impact on the base is comprehensive, since it can withstand constant load from the walls. And in cases where the house does not have a basement and the floor is located on the ground, the base is also subject to the pressure of the earth buried inside the entire perimeter of the house.

If, in order to determine the width of the future basement, it is necessary to accurately determine the choice of material from which the walls of the house will be built, and its type depends on the quality of the foundation, then the height will depend on the presence of a basement, temperature conditions, weather conditions and the amount of natural precipitation characteristic of that area where construction is taking place. These parameters vary greatly in different areas, so there are no strict guidelines for determining the height of the plinth.

Minimum height

The construction of the base begins directly from the foundation, and it is raised to a height of at least 40 centimeters. It is believed that this is the minimum height of the base of the house.

High base of the house

This height is optimal if there is a strip foundation, although a base of this height is erected on another foundation, based on the decade-average snow level that falls annually in a given area. A basement of this height is erected only in cases where the house does not have a basement.

In some areas, the height of the base of the house is lower than this indicator. In particularly arid zones, the construction of a brick structure is allowed to a height of only 20 centimeters. But even here there is a risk of excessive moisture in the walls of the house when ordinary rainwater gets on them. In most cases, a properly constructed blind area can change the situation. Although, with a low base height, as well as with improper construction of the foundation, the walls of the house may suffer from capillary wetting of the walls with groundwater. This will lead to destruction of the material from the inside and a significant reduction in the life of the building.

Standard height

Standard height plinth

The basement floor requires a significant increase in the height of the base itself. Now, to the main functions that this design is designed to perform, it is also added to ensure the installation of engineering systems in the technical room, which include pumps or valves. In some cases, when choosing the height of the base, they are guided by the height of the ceilings of the basement.

The features of the construction of the foundation of the house remain important. If the foundation level coincides with the ground level, then the height of the base cannot be less than 70 centimeters, and sometimes it reaches one meter. The standard height for the construction of a country house reaches 50 or 70 centimeters. It is this value that is considered optimal for most areas with varied climatic conditions and different depths of groundwater.

So, to determine the height of the base when building a country house, you need to take into account:

depth of groundwater;
amount of precipitation;
presence of a basement;
the need to organize a technical room in the basement;
view of the furnished foundation of the house.

Features of waterproofing and insulation at different heights

The effectiveness of the strip base will be reduced to zero if there are no ventilation ducts in it. These are holes, the distance between which should not exceed 3 meters. They are installed around the entire perimeter, ensuring high-quality air circulation. Internal walls and partitions are no exception. These openings can only be closed with ventilation grilles. In the video you will see how to properly insulate and waterproof the basement of a house.

The use of any plugs is strictly prohibited, since the humidity present in the basement space leads to the formation of mold and mildew. When building a brick plinth, to organize ventilation ducts, it is enough to leave gaps in the masonry; in other options, pipes are used that are fixed between the blocks. The jumpers can be sheet steel or ordinary reinforcement.

Reliable protection of the base from groundwater is provided by waterproofing material. This can be roofing felt or another type of rolled waterproofing, such as:

glass ruberoid;
rubemast;
euroruberoid.

Lay it in two layers directly on the foundation, applying bitumen mastic or heated bitumen to it. A layer of adhesive is applied between the layers of waterproofing material to ensure a strong connection.

Construction Materials

Peter Kravets

Reading time: 3 minutes

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When building a house, the height of the basement is taken arbitrarily, based on the wishes of the owner, who decided to make a room in the basement for various purposes, for example, a kitchen with vegetable storage. But when calculating, they still use data on the type of soil, type of foundation and materials used.

There are times when, when building a basement, they do not pay due attention to it, sincerely believing that it is enough to just take it beyond the surface of the earth in order to continue building the house. But this assumption is fundamentally wrong.

It is necessary to understand that the base is the part of the house located above the ground. And the greater the height of the basement, the less moisture penetrates inside. Groundwater, floods, precipitation - there are a lot of sources of moisture impact on the base, and this process occurs constantly.

Foundation walls must be separated by layers of waterproofing from the main part of a two-story (or more) residential building, since moisture still penetrates through the smallest capillaries into the material and significantly increases the level of humidity in the premises.

If a kitchen is installed in the basement, it is necessary to insulate it from moisture from the inside, since steam from processing products will form condensation.

When constructing a basement, you can use SNIP 2.08.01 for residential buildings and SNIP 2.08.02 for public buildings.

If the walls of the building are placed too low, the bottoms of the structure will constantly get wet, which will lead to their slow destruction and loss of thermal insulation properties.

As a result, the period of use of the building will begin to decrease, and it will not always be clear due to what factors. This explains the importance of the plinth occupying the required height from the ground surface.

Typical parameters for the height of the plinth from the ground according to the rules

To find out what the maximum height of a technical underground can be, it is necessary to clarify the minimum parameters. According to the requirements of building codes, in a residential country house the minimum height of the plinth should be approximately 0.3-0.4 m.

When installing with a wooden beam, this distance should be increased to 0.6-0.8 m. If the presence of a ground floor is provided, then the minimum height of the technical underground will be from 1.5-2 m.

To determine the height in a particular case, the climatic conditions of the construction site, the likelihood of flooding with melt and groundwater, the frequency and abundance of precipitation, indoor and outdoor temperatures (especially in winter) are taken into account.

If possible, to take into account all these factors, it is better to seek help from professionals, although theoretically, these calculations can be carried out independently.

This issue touches on the risks of repair and re-equipment of the structure, as well as significant financial expenses.

In order to understand why the optimal height of the base of a house is calculated, it is necessary to determine several of its functions:

Preventing the interior of the house from getting wet;
Compensation for shrinkage phenomena of the soil that occurs when the weight of the house structure puts pressure on it;
Protection of building facing materials from contamination;
High-quality ventilation of underground spaces (when arranging kitchens, additional ventilation ducts are installed);
Increasing the service life of the floor when using a strip or columnar foundation; in addition, the thermal insulation performance of the subfloor depends on the height of the base;
Improving the appearance of the building, since a house with a basement visually looks very presentable.

It is necessary to pay special attention to the height of the base when building from wooden beams, which are susceptible to rotting at the ends of the logs, which significantly complicates repair and restoration work.

With this type of construction, they try to reduce the likelihood of wood rotting; for this, the height of the base above the ground is increased. Practice shows that some builders make a huge mistake by trying to reduce this height and neglecting the base for the sake of aesthetic considerations.

Among the disadvantages of increasing the height of the base, one can only name the increase in the cost of building a residential building.

Important! In order not to rely on the advice of builders and your own considerations, it is important to know the regulatory documents, which indicate the verified minimum height with an explanation of the origin of these verified values.

For example, SNIPs 31-02-2001 and 2.08.01-89 (height of the basement) establish a height of at least 0.2 m for columnar and pile foundations. Such an indentation is necessary on heaving soils to avoid their impact on the house. The greater the slope of the ground, the higher the ground floor should be.

Types of socles

The construction of a basement may differ in type and sequence of work depending on the type of foundation. Most often, strip or pile foundations are used. In some cases, the base of the house is poured with a monolithic layer.

When choosing a strip foundation, the basement can be monolithic (in the form of a concrete wall) or masonry (in this embodiment, the foundation is made to the level of the ground surface, and then the masonry is erected - it is not enough to protect against various influences, therefore it is necessary to carry out insulation work and decorative finishing).

In relation to the walls of the facade, the plinth can be designed as recessed (for buildings with thick walls), protruding (the only possible for buildings where the basement floor and thin walls (apartment buildings)), and flush (part of the plinth smoothly passes into the facade, all parts of the house are located in one plane, usually one-story houses or a summer kitchen in the country).

The influence of the type of base on its height from the ground according to standards

The most expensive, but necessary option, is the protruding type. It is only possible for buildings with a used basement. The maximum height is taken for this case, otherwise it is impossible to achieve acceptable thermal insulation characteristics of the building.

For buildings without basements or a basement (most often a summer kitchen on a personal plot), it is worth choosing a sinking option. The facade overhanging wall will be optimal protection against mechanical and atmospheric damage. In this case, the height is taken to a minimum; the lower it is, the better the protection will be.

The base of the house is on one of the low foundations, usually made of blocks or bricks. It should be noted that the use of blocks significantly increases the strength and stability characteristics of the building.

Both types of execution require finishing work and insulation work. If groundwater passes close to the surface, then a drainage system is installed, and if it is deep enough, it is enough to make a blind area.

The foundation on piles can be low (if the grillage is located at ground level) or raised. Columnar, as the most unstable, requires a height of at least 0.2 m.

The gaps between the pillars are filled with bricks or shields. Due to design features, there cannot be an excessively high base. The arrangement on stilts with different height options can be found in the freely available photo.

Features of waterproofing and insulation at different heights

But no matter how thoroughly the strip foundation is built, its effectiveness can be reduced to zero if ventilation openings are not installed along the entire perimeter at a distance of no more than 3 meters from each other. They provide high-quality ventilation, as do internal partitions and walls.

Cover such openings with ventilation grilles to protect against the entry of debris, dirt and small insects into the room. The use of plugs for these purposes is strictly prohibited, since the inherent moisture in basements can lead to mold and fungal manifestations.

If a kitchen is installed in the basement, then you should also take into account the steam from processed products. Examples of this use of underground can be found in many photographs in open sources.

Important! In a public building, technical basements should be divided for fire safety purposes, by partitions into compartments of no more than 500 m2, in non-sectional residential buildings, and in sectional ones - in sections.