Usually project documentation the height of the basement of the house was also approved, however, in an effort to reduce spending on the foundation, the owners of the future building doubt the appropriateness of such a size if they are not going to operate it, that is, to arrange a basement or furnace. However, this important point for the entire object, on which not only the quality and sustainability, but also the durability of the entire building depends. Below are recommendations for optimal solution regarding the definition of parameters.
Basement - purpose and types
The ground floor, or as it is commonly called, the basement is the above-ground part of the foundation, which carries great importance both in design and operational terms. The following points depend on it:
- Protection of the house from interaction with soil moisture.
- The stable position of buildings is more than one floor.
- Compensation of the load of the entire object on the ground during shrinkage.
- The possibility of placing boiler rooms and cellars with a sine qua non ventilation. In this case, the base height wooden house must take into account the dimensions of the equipment inside the ground floor.
- Individuality in the matter of architecture.
Types of basement are different according to the architectural plan in relation to bearing walls and there are:
- Speakers. This is classical form, providing stability to the entire building, however, such a base must necessarily be protected by ebbs for water flow.
- Level with walls. Inexpressive in appearance, does not receive protection from moisture.
- Falling, that is, the walls go beyond their edges. For ignorant people, the shape causes an opinion about the instability of the residential structure as a whole, although it is reliably protected from moisture.
Not arranging a plinth means dooming a wooden object to rapid decay and, as a result, destruction. The savings on the basis will be mythical.
Plinth dimensioning
Many factors influence the arrangement of the above-ground part of the foundation. What height of the plinth to prefer depends on the purpose and conditions for the existence of the object.
The ratio of heights to a specific level is established by the design bureau in agreement with the customer, however, the following are strictly taken into account:
- The degree of deepening of the foundation.
- Capriciousness of the soil and the level of occurrence of aquifers.
- Climatic conditions of the area and freezing.
- Installation in the basement of heating devices or other purposes.
- The height of the object as a whole.
- Basement ventilation.
Specific regulation minimum size such a parameter as the height of the basement, SNiP provides for at least 20 cm for monolithic slab. But based on the fact that the strip foundation has become widespread, and the snow cover in middle lane Russia is approximately 1 m, then the ground floor cannot be less than this. Plus a blind area of 0.2 m.
It becomes clear that overall height will be 1.2 m. For log cabins from a light beam, an increase in height is recommended.
Features of the basement and its height during construction
They are based on the prevention of capillary processes and the preservation of heat - these are important qualities for any structure, and for wood they are also life-defining, given the enmity of moisture and building material. So:
At the design stage, it is worth making all the ideas and changes to the drawings - it is quite difficult to put into practice suddenly flashed desires during the construction process. Also, do not redo the package of sketches and architectural documents on your own - arbitrariness is fraught. In the design bureau, on the contrary, specialists will take into account all the nuances, in the implementation of which the object will only benefit.
Before starting any construction building structure, it is necessary to develop a competent and detailed project of the future structure.
Its mandatory component will be data relating to the characteristics of the base.
The project should contain information about, the depth of the underground part, overall dimensions soles, materials used.
The height of the foundation above ground level is also an important parameter. Many developers are trying to save on it.
A significant part of the total amount construction. Each individual developer strives to reduce these costs as much as possible.
And if, when calculating the width and depth of the base, we get the mandatory parameters that must be followed during construction work.
When constructing the above-ground part, you can use more accessible building materials and vary in height within certain limits.
What affects the height of the foundation
It should be understood that it depends on the aerial part of the foundation base how much the structure will be influenced by external climatic influences: temperature fluctuations and humidity.
To resolve the issue related to its height, it is necessary to figure out why raise the base above the ground at all:
- The above-ground part performs the functions of a basement cover. It is clear that the whole structure will have more best performance than a two-piece construction;
- The walls of the house receive additional protection from exposure to moisture. Even with a blind area, they are constantly moistened. Creating an intermediate layer reduces this effect. 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 data of the design documentation;
- For pile and column foundations, the level of the above-ground foundation cannot be less than 200 mm. This is necessary so that the heaving soil does not affect the building structure. In the presence of a slope, this distance can be large;
- When making calculations, it should be borne in mind that the house may shrink due to the characteristics of the characteristics of the soil and the pressure of 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 buildings made of wood, such as baths. In such situations, at the stage of carrying out design work provide for a high base, or other building materials are used in the construction of the basement.
How do the parameters of the foundation correlate
For example, consider how the parameters of the foundation are calculated during the construction of an individual house.
Practice shows that the ratio of the height of the elevated 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 underground part, but the opposite option is quite common.
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.
Foundation extension
Both the foundation and base structure have four various surfaces- upper, lower, inner and outer. Each must have a completely even surface.
An uneven base in the future can lead to deformation of the entire building structure. How to remove irregularities and, if necessary, increase the height of the foundation?
Most often, the raising of the base is carried out using solid bricks. It is used to strengthen and build up the base part to the right sizes. Reinforced mesh is used to strengthen the masonry.
When binding brickwork use cement mortar. When constructing frame or wooden buildings, it is used to strengthen the base. solid brick. 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 coating is carried out by manufacturing a new formwork structure and pouring concrete mortar;
- For small irregularities foundation with outer side lined with bricks;
- Instead, you can use a chain-link mesh. At the beginning, 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 visible under a layer of heat-insulating coating;
- For a perfectly even upper surface it is most convenient to use brickwork.
The level of the above-ground part of the base for a wooden structure
For wooden structure having a sufficient foundation height is especially important. This will prevent the process of decay of the lower part of the structure.
For the manufacture of such a base, brick, concrete, metal or wood can be used. Must be carried out high-quality waterproofing using coating or roll materials.
When choosing optimal height basement, 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 with bottom side but also from the side. For this you can use ceramic tiles or clinker.
If the base of the house is located high enough, its heat-insulating properties will improve and the duration of operation will increase.
findings
With a higher location of the foundation, the lower part of the building structure is better preserved. The optimum level above the ground is 0.4 m.
It should be remembered about the need for hydro- and thermal insulation works. This will protect the foundation from moisture and prevent the destruction of the reinforcing cage.
The video shows what height of the foundation above ground level is better to choose:
The height of the basement is one of the parameters that are of great importance when building a house. This is the lower part of the building, erected on the foundation and performing important functions related to the preservation of heat inside the room. The plinth is necessary in order to protect the walls from exposure ground water, it prevents the formation of fungus and mold on the walls, increases the resistance of the structure low temperatures. Due to the presence of the plinth, the heat exchange between the indoor and outdoor areas increases.
In order for this part of the house to meet all the requirements and contribute to the solution of the tasks set, it is necessary during construction not only to choose a quality and reliable material, but also take into account the height of the plinth being built.
How to determine the height of the plinth
One of the types of socle is sinking The effectiveness of the protective functions that the basement of the house performs directly depends on its height and type:
- Protruding plinth requires additional finishing and the construction of a visor that protects the structure from precipitation and moisture accumulation. It becomes a decoration of the facade of any building.
- Falling - the most durable. In this option, the joint of the basement and the walls of the house is completely protected from moisture, which is a guarantee of increased safety of the foundation and the protection of the waterproofing layer. During the construction of this type, there is no need to construct mandatory water outlets.
- Level with the wall. Least popular type plinth. It requires the construction of a visor, and when additional finishing is carried out, it becomes bulging.
The choice of the height of the plinth being erected is influenced by the type of foundation, the depth of groundwater, and the climatic conditions in the area where construction is underway. In addition, it is important to have a basement ( basement).
Starting work on the construction of the basement, it is worth considering that the higher it is, the less likely it is that interior spaces may be damaged by moisture penetration. Erections start directly from the foundation of the house, and at the joints with the walls of the building it is required proper organization waterproofing, preventing the possible penetration of moisture through the capillaries of the porous material into the walls of the building.
Plinth flush with the wall The impact exerted on the base is comprehensive, since it withstands constant load from the side of the walls. And in cases where there is no basement in the house, and the floor is located on the ground, the basement is also subject to the pressure of the earth, which is covered 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 regime, weather conditions and the amount of natural precipitation characteristic of the area where construction is underway. These parameters are very different in different areas, so there are no strict guidelines for determining the height of the base.
Minimum Height
The construction of the base begins directly from the foundation, and raise it to a height of at least 40 centimeters. It is believed that this is the minimum height of the basement of the house.
High plinth at home This height is optimal in the presence of a strip foundation, although a basement of this height is erected on a different basis, based on the decade-average level of snow falling annually in this 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 basement of the house is lower than this indicator. In especially arid zones, the construction of a brick structure is allowed up to a height of only 20 centimeters. But even here there is a risk of abundant moistening of the walls of the house when ordinary rainwater gets on them. In most cases, a properly constructed blind area can make a difference. Although with a low basement height, as well as with improper foundation construction, the walls of the house may suffer from capillary wetting of the walls with groundwater. This will lead to the destruction of the material from the inside and a significant reduction in the life of the building.
standard height
Plinth standard height Ground floor requires a significant increase in the height of the base itself. Now, to the main functions that this design is designed to perform, the provision of installation in a technical room is also added. engineering systems, which include pumps or valves. In some cases, when choosing the height of the basement, they are guided by the height of the ceilings of the basement.
Important are the features of the construction of the foundation of the house. If the level of the foundation coincides with the level of the ground, then the height of the base cannot be less than 70 centimeters, and sometimes it reaches one meter. standard height, during construction country house reaches 50 or 70 centimeters. It is this value that is recognized as optimal for most areas with a variety of climatic conditions and different depths of groundwater.
So, to determine the height of the basement during the construction of a country house, it is necessary to take into account:
- depth of groundwater;
- the amount of precipitation;
- the presence of a basement;
- the need to organize a technical room in the basement;
- view of the equipped base of the house.
Features of waterproofing and insulation at different heights
The effectiveness of the tape 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 arranged around the entire perimeter, providing high-quality air circulation. Interior walls and partitions are no exception. These openings can only be closed ventilation grilles. In the video you will see how to properly insulate and waterproof the basement of the house.
The use of any plugs is strictly prohibited, as the moisture present in the basement space leads to the formation of mold and mildew. When building a brick basement, it is enough to leave gaps in the masonry to organize ventilation ducts; in other cases, pipes are used that are fixed between the blocks. Jumpers can serve as sheet steel or conventional fittings.
Reliable protection of the basement from groundwater provides waterproofing material. It can be roofing material or another type of rolled waterproofing, such as:
- glass roofing material;
- rubemast;
- euroruberoid.
It is laid in two layers directly on the foundation, applying bituminous mastic or heated bitumen to it. Between layers waterproofing material apply a layer adhesive composition providing a strong connection.
- Why does a house need a basement?
- The basement of the house with two-layer walls.
- Peculiarities of basement waterproofing.
- Elimination of cold bridges in the basement.
The basement is the above-ground part of the foundation. It's a pretty complex knot. where the vertical (plinth, walls) and horizontal (floors and ceilings) structures of the house converge and adjoin each other.
The correct device, waterproofing and insulation of the basement - the necessary conditions for the construction of a durable, economical and heat-saving house.
The figure below clearly shows what will happen if the house has a very low base.
Plinth height not less than 20 cm. protects walls from moisture (pictured left) low plinth and the absence of a plinth leads to wetting of the wall of the house (in the figure in the center and on the right)
The height of the basement of a private house must be at least 20 cm. With a low base, there is a high risk of wetting the wall of the house. The walls will be moistened from splashes when raindrops hit the ground, when snowdrifts melt, or from capillary suction of moisture directly from the ground.
Damp walls lose their heat-saving properties. Water freezing in the walls gradually destroys them. Dirt, dampness, fungus and mold appear on the walls outside and inside the house.
In areas with high snow cover, it is better to make the height of the base not lower than the level of stable snow cover. This rule is especially important for houses with wooden walls.
To protect the walls of the house from moisture emanating from the ground, two lines of defense are created:
- Increase the height of the basement in order to remove the walls of the house as far as possible from the ground - a source of moisture.
- Arrange waterproofing of the walls of the house and the basement in danger zone exposure to moisture.
A high base increases the cost of building a house. Therefore, depending on the design of the walls and, they try to find a reasonable compromise between the size of the basement and the level of waterproofing.
Be sure to arrange between the basement and the wall of the house ghorizontal layer of rolled waterproofing.
In some cases, which are discussed below, it is necessary to do additional waterproofing of the walls of the house.
For a private house it is recommended to make a sinking base. At the sinking basement, the outer surface of the wall protrudes beyond the border of the basement by about 50 mm. Water falling on the surface of the wall flows down and falls from the wall past the basement onto the blind area. This solution does not allow water flowing down the wall to fall on horizontal waterproofing and flow into the wall along it. For better water drainage a dropper is fixed along the lower edge of the wall.
It should be noted that in addition to the moisture-proof function, the plinth plays a certain role in the architectural appearance of the house. A house on a high plinth looks more solid and spectacular, and the plinth finish can emphasize the beauty of the floors of the house.
Correct basement of a house with single-layer exterior walls
The height of the basement of a house with single-layer external walls must be at least 50 cm.(shown on the left) Or for plinth height less than 50 cm, but not less than 20 cm., additional waterproofing of the walls is required. (pictured right) The outer surface of single-layer walls is less protected from moisture than that of multi-layer walls. Therefore, the basement of a house with a height of at least 50 cm.
If the plinth of a single-layer wall is below 50 cm., then arrange additional waterproofing in two places:
- In the wall, above the first or second layer of masonry of aerated concrete or porous ceramic blocks, another layer of rolled waterproofing is laid.
- The outer surface of the wall, in the area of the lower rows of masonry, is protected from water by a layer of vertical waterproofing. To do this, it is enough to use hydrophobic primers and water-resistant plasters when finishing the wall. It is better, but more expensive, to clad the plinth and the lower part of the walls with a material with low water absorption, for example, clinker tiles.
Plinth construction for a single-layer wall basement houses or at home on foundation - slab can
Dimensions of the basement of a house with two-layer external walls
The minimum height of the plinth for a two-layer wall insulated with polystyrene foam is 20 cm. For a wall insulated with mineral wool, at least 30 cm.(on the left picture) A low plinth will result in moisture exterior finish and soaking mineral wool insulation (in the figure on the right) Besides, thermal insulation of the plinth eliminates the cold bridge through the plinth and the load-bearing part of the wall, bypassing the thermal insulation of the floor and wall.
In a single-layer wall, the floor is raised to the level of the second or third row of masonry. Raised to the same level vertical waterproofing plinth. 2 - waterproofing; 4-5 - plaster on the grid; 8 - finishing; 9 - floor on the ground If on site or weakly heaving, then the task of combating the forces of frost heaving is not worth it. In this case, it is necessary to get rid of only the cold bridge through the base and the bearing part of the wall.
To eliminate the bridge of cold in a house with single-layer walls without basement insulation, it is necessary to raise the floor to the level of the second or third row of masonry blocks outer wall. This is sufficient, since the material of a single-layer wall has a low thermal conductivity.
The bearing part of two- or three-layer walls is usually made of a material with high thermal conductivity. To eliminate the cold bridge in two- or three-layer walls, only upper part base, by about 0.5 m. below floor level. This will increase the length of the heat flow path along the base.
If the basement space under the house is not heated, then the basement is covered with thermal insulation on both sides.
In multilayer walls, to eliminate the cold bridge, one outer or both sides of the basement are covered with thermal insulation (for houses with unheated basement space or floors on the ground) For multilayer walls, another way to deal with a cold bridge is used. The lower rows of masonry of the bearing part of the wall are made of wall material with low thermal conductivity. The floor level is raised, similar to how it is done for a single-layer wall.
For insulation of the basement and the underground part of the foundation, extruded polystyrene foam slabs (penoplex, etc.) are best suited.
Convenient to insulate strip foundations. The design of pile foundations with bored (including TISE) or screw piles more suitable for a cold base. Insulation of such foundations is quite problematic and expensive.
The basement space of houses with pile foundations is usually not insulated. design basement floor and the floor of the first floor of the house on pile foundation chosen with this in mind.
Next article:
Previous article:
Always before the purchase of materials and the beginning of the construction of the building, its plan is created. It is especially important when designing to choose the right type of foundation, materials for its manufacture and desired height. Further, we will dwell on the last question in more detail and consider what the height of the foundation can be, the requirements of SNiP and why there should be a certain height for different structures.
Why is the height of the base given so much attention?
The requirements of SNiP quite clearly regulate the requirements for the base. It performs the task of supporting the entire structure and, if not properly constructed, the latter will not be able to guarantee safe conditions for people in use. In addition, destructive factors constantly affect the foundation, and especially in its outer part: winds, rains, snow masses, the sun, etc. Therefore, it must not only protect the structure from subsidence, but also raise the material of the walls two-story house or any other structure to a safe height. Let's take a closer look:
- It is great to use an elevated base as a plinth. In any case, there should be a height of walls above ground level regulated by SNiP. The advantages of using a plinth combined with a foundation are obvious - the construction of the structure will be more integral and stable.
- Some SNiP of certain materials require their remoteness from the aggressive effects of the earth: moisture, precipitation, etc. Otherwise, the lower layers of the walls may be destroyed, which can harm the entire building (especially in the case of a two-story house). As for the exact requirements, the base must be 10 cm higher than the calculated level of the maximum possible snow mass in winter period. Simply put, if a lot of snow falls, then the foundation should not be exactly hidden under it. As regards strip base, then the minimum height of the foundation above the ground is 30 cm.
- In some cases, an elevated base is a continuation of the walls of the basement of a two-story house. By analogy with the basement, a joint construction will provide many advantages.
- It is possible to create a high base as a measure to combat shrinkage, which is typical for some soils. Experienced planners always take into account all the features of the land on the site of the future building.
- Elevations within 20-30 cm are characteristic for pile foundation, as well as in cases of building a one- or two-story wooden house - the tree does not tolerate moisture.
Please note that even reliable waterproofing walls from the plinth side will not protect them from moisture and the only way out is to make a base with sufficient height to protect against moisture.
Height of the strip base
It should be borne in mind that the entire height of the foundation consists of 2 parts: underground and aboveground. If you listen to the recommendations of experts, then it is optimal when it rises 40 cm from the ground. This indicator can also be influenced by the amount of precipitation and the material for laying the walls. For example, when using structural aerated concrete, much less elevation is required than in the case of cinder block.
If there are no special requirements for height requirements, then the SNiP documentation should be taken into account when determining the depth. It indicates the levels of freezing of the main types of soils and the indicators of base height recommended in each situation:
- The soil is slightly heaving: freezing is 300-350 cm - the recommended foundation depth is 150 cm, 250 cm - 100 cm, 150 cm - 75 cm, 100 cm - 50 cm.
- Non-porous: more than 300 cm - 100 cm, up to 300 cm - 75 cm, 200 cm - 50 cm.
Also, when determining the depth, the level of groundwater is taken into account.
Determination of the height of a monolithic base
It is worth considering some points:
- The SNiP rules regulate the minimum height of such a base at 20 cm. To be more precise, this is exactly what the height of the base should be. But in regions with uneven rainfall, this indicator in the case of the construction of a two-story wooden house is increased to 40 cm - this allows you to protect the tree from moisture.
- Also, in cases where the soil freezes up to 1 m, then the foundation must be installed deeper.
- The advantages of a monolithic slab include its complete insensitivity to displacements of soil masses. But in the case of construction on sites with characteristic seismic activity, the width of the foundation should be increased.
General results
- The smallest height of the tape base is 30 cm above ground level;
- Great if the foundation performs the task of the base;
- The wall material should be protected from moisture as much as possible;
- It is necessary to make such a foundation so that at maximum precipitation it is 10 cm higher than the snow.
Approach the design correctly and it does not matter whether the construction of a two-story house, a bathhouse or utility room. A well-chosen foundation height above the ground will extend the life of the structure for a long time.
The height of the foundation for the house updated: February 26, 2018 by: zoomfund
