How to build a house on an old foundation. How to build a new house around an old one: step-by-step instructions Using an old foundation for a new house

Building a house even on a free plot is not the easiest thing. It’s even more difficult if there are buildings on the land plot that you no longer need, but want to build in their place new cottage or townhouse. Today we will figure out how to build a house on a plot that is still occupied by another building.

Building a house even on a free plot is not the easiest thing. It’s even more difficult if there are buildings on the land plot that you no longer need, and in their place you want to build a new cottage or townhouse. Today we will figure out how to build a house on a plot that is still occupied by another building.

The situation described above is far from hypothetical; a very specific example can be given. A family with three children inherited a plot of land with a house built around 1979. It would seem that this is freedom, you can do whatever you want. But, upon reflection, the couple came to the conclusion that everything is not so simple. First, what to do with an old house? It is, of course, theoretically possible to live in it: there is stove heating and electricity. But I want it better! So that there is gas, running water, a civilized heating system for the premises. And the house should be two-story, so that each family member has his own room.

The old house by no means fit into the image of an ideal family nest. Therefore, the new owners decided, it must be demolished. And put a new one in the vacant place. New questions immediately arose: demolish it completely or leave the foundation? Do I need to obtain a demolition permit? Is it any good? old foundation for a two-story new house? How then to coordinate the new construction with the BTI? We asked real estate market experts about all this.

Down to the ground and then

First of all, you need to think about what problems might arise if you leave the old foundation and build a new building on it. Yulia Severinenko, general director of the ZemAktiv company, believes that it is necessary to first conduct an inspection of the old foundation. This is done by specialists who will evaluate the technical condition of the existing foundation, the properties of the soil at its base, and the suitability of the structure for future loads. As a rule, if it is, for example, a monolithic reinforced concrete foundation, which was made correctly at one time, it will be possible to erect a new structure on it from any material.

True, if the foundation was poured back in Soviet times, then it is unlikely to be in decent condition. “In 1979, no one made foundations according to modern technologies. High-grade concrete was in short supply, and few people followed the technology in low-rise construction. Based on a foundation that has been standing for 30 years, you can almost immediately tell whether it will stand for another 100 years, or whether it has already practically “died,” says Alexander Dubovenko, development director of GOOD WOOD.

Therefore, the owner of an old house needs to decide whether to spend money on an examination of the condition of the foundation.

In addition, in any case, you need to check the documents for the land, even if you are going to build a house on the site of the old one, without changing the development plan, because, as practice shows, land and houses purchased or built before the 90s were often not registered. “From a legal point of view, it is possible to build a new house on an old foundation if the land is owned and the permitted use of the land includes the construction of a house,” explains Alexander Sergeev, legal adviser to the Volzhskie Dachi Management Company.

However, if the object was transferred by inheritance or as a gift, then problems with registration of ownership, and therefore with the disposal of this property should not arise.

Demolition or reconstruction?

Experts note that obtaining a demolition permit depends on many factors, in particular, on the nature of the supplied communications and the requirements of utility services when reconnecting them. “Therefore, in order to simplify approvals, owners often demolish a house and build a new one under the guise of reconstructing the property, or use similar schemes,” says Yulia Severinenko.

Irina Bashilova, head of the legal department of the Volzhskie Dachi Management Company, believes that registering the construction of a new house on an old foundation as “ major renovation"or "reconstruction" of a previous house is quite possible, but you need to be very careful about the process. “The substitution of concepts will be advisable only if we are talking about “major repairs” or “reconstruction” that do not affect the structural and other characteristics of the reliability and safety of a capital construction project and (or) its parts and do not exceed the maximum parameters of permitted construction, reconstruction established by urban planning regulations. Only in this case, in accordance with Art. 51 of the Town Planning Code of the Russian Federation, there will be no need to first obtain a construction permit, and after the construction of a residential building, a permit to put the facility into operation,” the expert warns.

Therefore, it seems that it is better to completely demolish it. an old house along with the foundation in order to build a new cottage on the vacant plot. By the way, the majority of Sobstvennik readers think the same thing: according to the results of our survey, 36% of respondents would prefer this option.

Demolish, cannot be pardoned!

Now let's see what needs to be done to properly formalize the demolition of the structure. Alexander Sergeev emphasizes that the owner of the house has every right to dispose of his property, including destroying it, and if the house is registered in the cadastral register, then it will need to be removed from this register.

But first you need to carry out the actual demolition, and then contact the BTI authorities to draw up a house inspection report. “Based on the inspection report, the BTI will cancel the record of the existence of the house. After this, you need to contact the Rosreestr department with an application to make a record of the cessation of the existence of the old house,” explains Maria Bondarevskaya, a lawyer at the law firm Yukov, Khrenov and Partners.

Concerning technical features demolition, it is necessary to demolish the house itself, as well as the basement part of the foundation to ground level, since dismantling the underground part will be very expensive. “For example, you will have to drill out piles laid several meters deep, or tear up a foundation pit in order to remove concrete that was once poured,” says Yulia Severinenko.

In these cases, the expert believes, it is better to shift the new foundation slightly so that it does not coincide with the old one. If it is important that the new house stands on the same spot of wall-to-wall construction, it will be necessary to dismantle and underground part. But it's extremely expensive.

After demolition, the site will need to be prepared for new construction. “It is necessary to remove construction waste, plan the territory of a new construction site, equip an entrance to the site (for construction equipment), install temporary structures (cabins) for storing materials, tools, accommodation for builders, carry out engineering preparation (providing the site with electricity, water, sanitary cabins)” , - advises Dmitry Yazykov, construction director of the Zagorodny Project company.

• Date: 04-09-2014
• Views: 1525
• Comments:
• Rating: 28

First of all, you need to talk about how to build a house on an old foundation and, in particular, why they do it. This trend in the modern cottage construction market, such as rising land prices, forces many to buy a plot of land with an existing house. However, it is often impossible to live in such a house and the owners decide to demolish the house. The house is demolished, and in its place the old foundation remains as evidence of the previous construction.

Of course, it can either be dug or buried. But why neglect the opportunity to use the former foundation as the basis for a new house? After all, money was spent on it, even if by another person. And the construction of a new foundation can take up to 30% of the entire cost of the house. Therefore, it makes more sense to build a new house on the site of the old foundation - it is much easier and more profitable to restore the former foundation than to build a new one.

Replacement, repair and strengthening of the foundation

Finding ways to strengthen the foundation of the previous house.

If in the old house before demolition there was skewed door and window openings, this is the first sign that the foundation will have to be repaired, strengthening or restoring it completely.

This procedure differs from conventional repairs in that it will entail a significant waste of money and the involvement of third-party specialists.

Return to contents

Finding the causes of foundation failure

Many methods and methods have been developed to strengthen the old. Although there have been many technological innovations, the old techniques have already stood the test of time. They can be both expensive and cheap. To find a suitable method, you need to proceed not from its cost, but from taking into account the repair requirements in each specific case. It is imperative to follow the technology used.

Return to contents

Strengthening the strip foundation

As the foundation of a house strip foundation used more often than other types. It can be characterized as a solid structure, however, some of its parts allow a load greater than that determined by design standards. This design of the base of the house is subject to local heaving phenomena. As a result, a distortion of the building appears, since on one part the pressure will be disproportionately greater than on the other.

How to strengthen old tape? All work will be aimed at equalizing the impact of underground forces. The most expedient way to do this is by creating additional area for the foundation of the house. Work begins from the part where the tilt is recorded.

First, select a section of the wall about 2 m long. Next, reinforce the base under future home according to a certain scheme. A trench is being dug near the house.

The depth of the pit should be such that the lower boundary of the damaged part is 1 m above the bottom of the pit.

The width of the new base is calculated based on the data obtained.

Often it coincides with the width of the old foundation, but sometimes a new foundation is laid 1.5-2 times wider than the old one.

Then the old foundation is prepared for joining with the new one. To do this, holes are drilled for grooves and reinforcement, where new concrete will be poured. After this, formwork is arranged for a new foundation, and a frame is knitted from reinforcement. Subsequently, it will be coupled to the existing reinforcement.

When the frame and the house are connected, a concrete solution is poured, which penetrates the grooves and cements the pieces of reinforcement. Then wait until the solution hardens completely. Then the new foundation is buried and a new trench is dug. On one side of the wall it is allowed to work only with one section. To speed up the work, work can be done from the other side.

All procedures at home must be carried out at a fast pace. If the building remains idle open form long, this will make it sag much faster.

Return to contents

Strengthening the foundation of a house located deeper than the frost line

It also happens when its base lies below the freezing line of the soil. This type of foundation practically does not experience the lifting action of the soil. However, another problem can happen to it - groundwater can wash away all the soil from under it. This may explain the need and importance of performing drainage work before strengthening the old foundation.

First of all, install drainage system, then the foundation, which has already been subjected to the destructive effects of groundwater, is removed. After this, they move directly to restoration and repair work.

To strengthen the foundation of an old house, a number of works are performed by analogy with. Upon completion of the work, it is recommended to install additional waterproofing so that water cannot cause more damage to the building.

Houses are not an easy task, even if the plot of land allocated for construction is vacant, or if the land plot already contains construction projects that the owner does not need. In this case, building a house is complicated by the need to resolve legal issues and overcome a number of technical obstacles.

Quite often there is a situation when, instead of an old house or cottage, it becomes necessary to build a new one. In particular, a house with a plot can be inherited, and you may be faced with a solution to the problem - stay in the old house with stove heating or build a new house with all the attributes of civilization inherent in modern construction - running water, a full-fledged heating system and gas.

If the old house does not fit into the idea of ​​comfortable ideal housing, it would be wiser to take up the issue of building a new one. However, a number of questions immediately arise before the developer: is it worth reconstructing or is it better to demolish? Is it possible to leave the old foundation? Is a demolition permit required in this case? How to coordinate a new building with the BTI?

First of all, before building a new house, it is necessary to understand the condition of the foundation of the old building, for the examination of which you need to invite specialists. The assessment of the old foundation is carried out according to several parameters - optimally withstand loads, compliance with the parameters of the planned house, soil properties, and the technical condition of the existing foundation. A high-quality monolithic reinforced concrete foundation, even if its service life exceeds thirty years, does not require reconstruction in most cases and is suitable for the construction of a new house.

However, often houses that were built thirty years ago are on dilapidated foundations. According to expert reports, construction houses at that time it was carried out mainly using standard methods, which were far from modern ones. Plus, high-quality concrete was in short supply and most of technologies low-rise construction was not followed. In order for a competent specialist to say for sure whether the foundation of an old house will be “livable” or not, it is necessary to conduct a minimal study of it.

Of course, the services of this specialist will cost the future developer a certain amount, but if the result is successful, the developer will be able to save on the construction of a new foundation.

If a decision is made to build a new house on the site of an old one, it is necessary to check the land documentation. Even if you plan to build a house in the same place, there is a possibility of getting into trouble with the law, because land plots and houses built or purchased before the nineties were often not registered. According to experts, with legal side It is possible to build a house on the site of an old one only when the land is recognized as the property of the developer. Even if the land and object were inherited or donated, there should be no problems with registering the site.

According to experts, before building a house, many people prefer not to obtain an official demolition permit, and carry out demolition and construction under the guise of reconstruction or major repairs. The reason for this is the complex points in the design of some issues, which are related, in particular, to the communications connected to the old house and the subsequent requirements of utility services for their reconnection.

Register the construction of a house on the site of the old one as “major” repair“or “reconstruction” is possible, but it is necessary to deal with the assigned tasks step by step and very carefully. It is advisable to replace the concepts only within a strictly limited framework, without exceeding the parameters of permitted construction established by law.

For most developers, all the requirements and instructions are too complex, so they completely demolish the old buildings along with the foundation and build a new house on this site, applying for a regular building permit.

Demolition clearance is another step that needs to be addressed before preparing for construction. The peculiarity of this procedure is that first you need to carry out the actual demolition and only after that, in order to draw up an act, contact the BTI.

The demolition of an old house from the technical side should be carried out as follows - the building must be demolished down to ground level, otherwise, demolishing the foundation can cost the developer a pretty penny. The need to dismantle the underground part arises only when the construction of a house will be carried out on the site of the old one.

Building a house is not an easy task, even if the plot of land allocated for construction is vacant, or if there are already construction projects on the land plot that the owner does not need.In this case, it is complicated by the need to resolve legal issues and overcome a number of technical obstacles.

Quite often there is a situation when, instead of an old house or cottage, it becomes necessary to build a new one. In particular, a house with a plot can be inherited, and you may be faced with a solution to the problem - stay inan old house with stove heating or build a new house with all the attributes of civilization inherent in modern construction - running water, a full-fledged heating system and gas.

If the old house does not fit into the idea of ​​comfortable ideal housing, it would be wiser to take up the issue of building a new one. However, the developer immediately faces a number of questions: is it worth reconstructing or is it better to demolish? Is it possible to leave the old foundation? Is a demolition permit required in this case? How to coordinate a new building with the BTI?

First of all, before building a new house, it is necessary to understand the condition of the foundation of the old building, for the examination of which you need to invite specialists. The assessment of the old foundation is carried out according to several parameters - optimally withstand loads, compliance with the parameters of the planned house, soil properties, and the technical condition of the existing foundation. A high-quality monolithic reinforced concrete foundation, even if its service life exceeds thirty years, does not require reconstruction in most cases and is suitable for the construction of a new house.

However, often houses that were built thirty years ago are on dilapidated foundations. According to expert reports, the construction of houses in that period was carried out mainly using standard methods, which were far from modern ones. Plus, high-quality concrete was in short supply and most low-rise construction technologies were not followed. In order for a competent specialist to say for sure whether the foundation of an old house will be “livable” or not, it is necessary to conduct a minimal study of it.

Of course, the services of this specialist will cost the future developer a certain amount, but if the result is successful, the developer will be able to save on the construction of a new foundation.

If a decision is made to build a new house on the site of an old one, it is necessary to check the land documentation. Even if you plan to build a house in the same place, there is a possibility of getting into trouble with the law, because land plots and houses built or purchased before the nineties were often not registered. According to experts, from the legal side, it is possible to build a house on the site of an old one only when the land is recognized as the property of the developer. Even if the land and object were inherited or donated, there should be no problems with registering the site.

According to experts, before building a house, many people prefer not to obtain an official demolition permit, and carry out demolition and construction under the guise of reconstruction or major repairs. The reason for this is the complex points in the design of some issues, which are related, in particular, to the communications connected to the old house and the subsequent requirements of utility services for their reconnection.

It is possible to formalize a “major repair” or “reconstruction” in place of the old one, however, it is necessary to deal with the assigned tasks step by step and very carefully. It is advisable to replace the concepts only within a strictly limited framework, without exceeding the parameters of permitted construction established by law.

For most developers, all the requirements and instructions are too complex, so they completely demolish the old buildings along with the foundation and build a new house on this site, applying for a regular building permit.

Demolition clearance is another step that needs to be addressed before preparing for construction. The peculiarity of this procedure is that first you need to carry out the actual demolition and only after that, in order to draw up an act, contact the BTI.

The demolition of an old house from the technical side should be carried out as follows - the building must be demolished down to ground level, otherwise, demolishing the foundation can cost the developer a pretty penny. The need to dismantle the underground part arises only when the construction of a house will be carried out on the site of the old one.

Increasing the usable space in a private property by adding new premises that stand on their own foundation begins with solving the problem of how to connect the foundation to the house so as not to damage both structures. The construction of additional structures usually begins after several seasonal cycles, during which financial resources have been accumulated, a desire has appeared for a new round of site development, and the standing buildings have begun to shrink normally in the ground. Building codes give the answer to how to connect two foundations to each other, taking into account mutual influence.

Connection requirements

It is necessary to determine how to connect the new foundation of the extension with a residential building at the design stage, taking into account already existing factors. These include the following incoming conditions:

• type and design indicators of the foundation of the existing building;
• characteristics of underlying soils;
• time elapsed since the previous construction (the main shrinkage occurs in 1 - 2 years);
• commensurability of the weight load of 2 structures that need to be combined.

Full requirements for the calculation are contained in the set of rules SP 50-101-2004, which was developed in development of the regulatory rules contained in SNiP 2.02.01-83 *, SNiP 3.02.01-87.

In any case, the help of experienced professionals is not superfluous, since mistakes can be costly later.

The result of linking the base and attached building structures With different sizes shrinkage of the bases is shown in this video

The construction of a new building begins depending on the season. In the spring, it is not recommended to start laying next to existing foundations, since at this time of year the soils are in the most loose and water-logged state. The settlement value of a new extension on heaving soil may be much greater than the calculated value in the project and may be uneven around the perimeter. At the same time, there is a risk of movement of the undermined old support due to the high groundwater level in combination with possible precipitation (rain or snow).

Before starting work, it is necessary to take into account that any new foundation (MZLF, piles, pillars, slab) will certainly settle, even if it is made identical to the existing support.

Shrinkage

In construction, there are established settlement standards for various structures, the foundations of which are designed and manufactured in accordance with current state standards.

Find out the standard and make a forecast for the design of your individual house using the data from the reference tables:

When comparing the calculated indicators, a new support unit is attached to the foundation of the old building at a given depth, taking into account its own settlement after a certain time.

The upper marks of monolithic strip foundations of combined buildings are made according to calculation, and not according to level, as in this photo.

It is the possibility of displacement relative to each other that determines what kind of connection between two foundations can be made. The following types of connections are used:

1. Rigid bond (concrete with reinforcement).
2. Separate installation (installation of an expansion joint taking into account the mutual influence of the supports).

The possibility of a rigid connection into a single structure is significantly influenced by the geological factors of the site - in case of mobile or heterogeneous soils, for buildings with a large support area, it is necessary to make intermittent foundations (sometimes with different widths of the tape).

Start of independent construction of a new extension module to residential building acceptable if the following requirements are met: issue permits for installation new design, maintain distances no closer than the minimum permissible to adjacent buildings and communications, ensure independent settlement of all structures in relation to each other.

Combining foundations

The new premises are best attached to existing foundation at home with a rigid coupling. In this case (if all conditions are correctly taken into account), it is possible to connect the above-ground surfaces into a single whole without the expectation that gaps and distortions will appear between the elements and the floor level. But such a design solution is limited to sites with non-heaving soils that have high load-bearing characteristics.

In practice, this method is used for low-rise buildings, provided that the extension being built is functionally connected by one roof to the building that is already in use.

Another condition for unification is the same type of foundation. If the strip base of a residential building turns out to be insufficiently wide, then it needs to be strengthened.

Such work includes connecting the reinforcement of an old support with a new frame or laying connecting anchors by drilling, followed by filling the belt with branded concrete. The reinforcement belt prepared for applying the solution is shown in this photo.

The connection of buildings consisting of several floors is carried out using more complex scheme, which involves the construction of covering walls with dividing seams on each side, as shown in the drawing.

The rigid type of connection is chosen for cases when the problem of how to connect an old established foundation with a new building is considered, for buried strip foundations. The extension is also designed with a monolithic reinforced concrete structure.

Strip foundations

For a permanent premises attached to a house, having a commensurate weight of the used building materials, a stable support of large area and load-bearing capacity is required. This request corresponds in most cases to a strip foundation.

1. Expose the entire depth of the existing tape. You need to dig a trench in parts (1.5 m - 2 m), not along the entire length at the same time, since the exposed part loses lateral support, which can lead to its deformation. An old building can be further strengthened with inclined supports.
2. Drill holes along the side of the connection corresponding to the size of the reinforcement Ø. In the middle of the tape, holes are drilled in a checkerboard pattern with a depth of about 0.75 of the width of the foundation itself, in the corners - 0.5 m. Reinforcement is driven into the middle holes, in which longitudinal slots are made with an inserted wedging liner for strong fastening in the hole. Reinforcement Ø 14 mm, having a periodic profile, is driven into the corner holes. The output of rods must be at least 0.3 - 0.4 m.
3. The frame of the new foundation is knitted and welded to the released reinforcement.
4. Fill with concrete mortar.

If there is access to the subfloor for work, the holes for pin-type tension elements can be made through, with the rods secured by flat plates.

Rigid connections of tapes in the form of an open contour (U-shaped) are made in the same way, but the reinforcement is placed in rows with smaller spacing. If the connection side is long in the open strip, you can make several additional support points different from the monolith, as can be seen in the photo.

If there is a need to change the depth of support on the soil of the foundation being added, it is filled with ledges, the height of which varies in steps of no more than 0.5 m. The first ledge is located at a distance of about 1 m from the old foundation. The connection is made with a reinforced concrete strip of the same thickness as the existing foundation of the house.

Each option for rigid connection of foundations has its own characteristics for specific cases, which it is advisable to entrust to professionals to consider and calculate.

Plates

Ensure connection rigidity slab foundations houses and extensions are possible provided they are sufficiently thick, about 0.4 m, and also if there is an existing protrusion of the old slab beyond the boundaries of the supporting walls of the building. Such protrusions are usually left during the construction of aerated concrete cottages. The outlet dimensions must be at least 0.3 m. This will make it possible to clean the reinforcing mesh of the slab and make welded joint with the frame of the new extension.

The connection of monolithic bases is carried out according to the following scheme:

The slab of the old house, which has already settled, in this case not only becomes one with the new fill, but also receives additional reinforcement in the vertical connection of cement mortars due to 0.2 m - 0.3 m of fill underneath it.

Separate supports

If there is a large discrepancy in the weight of the old and new structures, the degree of shrinkage of these structures will differ significantly in magnitude. In such cases, it is not recommended to make a rigid connection for the foundations - it is necessary to choose separate construction of the supporting elements. It is possible to attach other types of foundation to the existing foundation and to do this use the principle of connection through an expansion joint.

The weight of the ceilings and walls of the extension should be distributed over its own support area, without creating tearing forces for the main foundation of the building.

Depending on the operating conditions, the expansion joint can be:

• sedimentary;
• temperature;
• seismic.

The sedimentary option (in the absence of other significant influences) has a width of 1 - 2 cm. According to the conditions of the mutual influence of the supports, the connection to load-bearing wall of an old house can be performed with a deformation gap reaching 0.2 - 0.4 m, filled with elastic, moisture-proof material.

Frame wooden extensions are successfully used in pile foundation with a metal grillage, as in this photo.

Light verandas or summer kitchens can be attached to screw piles, even if there are already several adjacent buildings around. This is especially convenient if the site is located on a slope, slope or with uneven occurrence of hard supporting rocks.

At the design stage, the external design of expansion joints that visually separate the facade is envisaged in an open or hidden form, for example, hiding the gap with a subvertical drainpipe. On the façade side, they are usually covered with strips of a special flashing and sealed with low-strength decorative material, which will not prevent the outer walls of buildings from moving relative to each other with possible uneven settlement. Under the roof deck, gaps are bridged using a compensation device.

An extension to a house, installed on separate supports, is a much less labor-intensive process than installing a rigid link, requires significantly less time and financial costs, and can also be done with your own hands without ordering special equipment

A far-sighted solution is to provide for the possibility of an extension at the design stage of the main building of a private house. This will greatly simplify subsequent work and will contain ready-made Constructive decisions, planned uniform settlement over the entire laying area and will ensure the reliability of the foundation.