After the time has passed, residents of a private or apartment building may notice certain problems with the design of the building itself. The walls of the basements or first floors begin to “watery” from the inside, sometimes small puddles of water appear under them. This is one of the obvious reasons for the poor-quality waterproofing of the foundation with your own hands and the penetration of groundwater. There is only one way out of this situation - to carry out the work again and restore the drainage system.
Many homeowners are perplexed why this could happen, and who is to blame for this situation. As a rule, in multi-storey buildings this happens due to the mistake of the designers or performers of the work, as well as the organization accepting housing for operation. In private construction, the customer is ultimately to blame for not controlling the required quality of this stage of construction.
Consider the main mistakes that lead to the need to re-waterproof the foundation of a built house:
- The lack of waterproofing of the base of the house in principle. This can be done inadvertently or because it is not necessary, for example, in the case of dry ground, in which the water table is located at a depth of more than 10 meters.
- The performance of poor-quality waterproofing of the foundation is one of the most common reasons leading to the repetition of work. This can happen due to the lack of the necessary qualifications of workers, not attaching particular importance to the process.
- The use of materials that do not meet the requirements for the specific conditions in which the base of the house is located.
Methods for external waterproofing of the foundation of a finished house
If the building has already been built and put into operation, if the residents have discovered a problem after years of living in the house, you should not despair, since it is possible and necessary to waterproof the foundation with your own hands or by using specialized organizations. To perform this type of work, there are several ways, both more physically and financially costly. In any case, re-waterproofing the foundation of an old house will require a lot of effort and patience.
Coating insulation of vertical surfaces
The simplest, but also the least high-quality method that is available for do-it-yourself work is the implementation of coating waterproofing. The sequence of the main stages of work is as follows:
Foundation insulation with rolled materials
Do-it-yourself coating waterproofing of the foundation of an already built house with bituminous mastic often does not meet the high requirements for it, since fragile compositions can be mechanically destroyed even under the influence of gravel from the soil. This drawback is deprived of insulation, carried out using rolled materials - films or membranes.
Preliminary preparation of the surface of the strip foundation of the house is similar to that described above. Often pasting with roll materials is performed in conjunction with the use of bituminous mastic, which acts as an underlying layer. After finishing with a primer and applying coating insulation, the latter is kept until it hardens.
Next, the sticker of rolled materials is performed. Some of them have a pre-applied adhesive seam, which greatly facilitates the installation process. For adhesive-free films, special polymer compositions are used. Before sticking, the bituminous mastic is preheated with a gas burner. This improves adhesion.
To prevent the penetration of groundwater, the films are released onto the ground near the base of the foundation by 0.2-0.3 meters. In addition, it is necessary to follow the following rules for waterproofing the foundation with rolled materials:
- To increase the strength of the waterproofing of the foundation, laying a thin reinforcing mesh made of plastic or galvanized wire on the coating mastic helps;
- It is necessary to overlap vertical sheets on each other by at least 10 cm;
- If it is necessary to vertically apply one sheet to another, it is necessary to overlap by at least 20 cm. In this case, the upper piece should be applied to the lower one, and not vice versa.
- You can make the waterproofing of the foundation better by performing several layers of gluing with sheet materials.
Waterproofing with building mixtures
Another simple way to waterproof the foundation with your own hands on an already built structure is to apply special plaster compositions to the vertical external structures of the base of the house. Standard cement plaster is not suitable for these purposes due to its high hygroscopicity. It is necessary to purchase mixtures with polymeric fillers that close concrete pores.
Do-it-yourself waterproofing of the old foundation by plastering is carried out in the same way as the previous types, after the entire base of the house is completely freed from the ground. If groundwater is not deep and is present at the place of work, you can not do without making a drainage system with your own hands. Its task is to maximize the removal of moisture outside the site.
The cleaned foundation must be dried and applied with two coats of a standard building primer using a fur roller. An even layer of polymer-containing plaster about 1 cm thick is applied on top of it with a steel spatula. After the base layer has completely hardened, two more are applied, each of which is equal to the previous one. Thus, the total thickness of the waterproofing of the foundation of the built house should be about three centimeters.
It should be noted that of all the options described above, this method is the fastest, most affordable for doing it yourself and the least financially costly.
External waterproofing from inside the house
If there is an operated basement in the house, it is possible to waterproof the foundation from the inside. But this technology is complicated, it requires the use of special construction equipment, the cost of renting which is comparable to the cost of all external insulation work on our own.
The technology of waterproofing the foundation from the inside consists of the following steps:
- The internal surface of the foundation is examined for cracks;
- A series of deep holes are drilled in the plane of the base of the house, located at an angle of 45 degrees to the horizon.
- The pits are blown by a compressor to extract cement dust;
- Special receiving-conductive devices called injectors are screwed into the holes;
- By connecting special injection equipment, special compounds are pumped into the holes under pressure, which dramatically increase the moisture resistance of concrete.
Foundation waterproofing at the top
The most difficult type is the so-called horizontal waterproofing. It is carried out over the base of the house at the junction of it with the material of the walls. In its absence, brick, blocks or wooden building elements begin to quickly collapse under the influence of moisture coming from concrete.
There are several ways to perform horizontal waterproofing of the base of a built house, which differ depending on one or another wall material. The simplest type is the protection of a wooden timber or log house.
Horizontal foundation protection under wooden walls
Do-it-yourself waterproofing of the foundation along its upper end is traditionally performed using coating and roll waterproofing. In the case of a house whose walls are made of wood materials, the process is carried out as follows:
- The log house is pre-stitched along all the walls using long boards at least an inch thick. Through the lumber, two self-tapping screws are screwed into each crown or two nails No. 100 are driven in. This technique will prevent the possible displacement of parts relative to each other when the log structure is raised.
- Jacks are alternately brought under each corner and lifted by 5-10 cm, hanging the entire structure on additional supports;
- The upper edge of the released foundation of the house is smeared with bituminous mastic or bitumen heated to melt;
- Roofing material is rolled onto the coating in two layers.
- Gradually, the structure is lowered onto the treated base and additional screeds are removed.
Waterproofing the foundation of a brick house
The most difficult option for horizontal waterproofing is the implementation of this type of work in a brick or block house. The difficulty lies in the need to separate the two structures, which are connected by cement mortar along the perimeter. It is better to entrust this work to professionals, since it is practically impossible to waterproof the foundation if the house has already been built using this technology with your own hands.
The list of actions in this case will look like this:
- Determine the junction of the base and masonry;
- In small pieces, with the help of a grinder, a part of the wall material is cut out;
- The resulting cavity is filled with bitumen and roofing material;
- The remaining space is laid with cement mortar and allowed to dry completely.
Penetrating horizontal insulation
Similarly to the vertical penetrating, it is possible to waterproof the foundation at the junction with the walls. The technology of the process is no different from that described above. The difference is only in the direction of drilling holes in the concrete base. It runs strictly horizontally. The pitch of the pits should not exceed 10-15 cm. For better penetration, it is recommended to heat the solution to be filled up to 35 ° C.
