The construction and arrangement of the foundation must be approached responsibly and very carefully, since the durability of the house will directly depend on these activities.
The foundation is influenced by ground, capillary and surface water. As a result of their combined impact, the foundation is deformed and sags.
As you know, concrete very well absorbs moisture, which subsequently rises through the capillaries in its structure. Also, this moisture subsequently penetrates into the floor and walls of the house. This creates ideal conditions for the reproduction of fungi and mold.
Alternate thawing and freezing of water has a huge negative impact on the foundation. It penetrates into the pores of concrete, and then freezes in them. Its subsequent thawing causes the destruction of the foundation.
To avoid all negative factors and keep the foundation intact, timely waterproofing should be done. Of course, you can save money and not perform waterproofing, but then repairing the foundation will cost more than building a new box at home.
But waterproofing is done according to certain rules, otherwise all the work will be done in vain. Laying technology requires an understanding of all processes occurring in concrete and soil. This article will cover all the details regarding the correct installation of waterproofing.
Foundation waterproofing technology
First you need to outline the circle of all upcoming events. To do this, you need to take into account the starting conditions:
- depth of groundwater;
- operating conditions of the house;
- the force of "swelling" of the soil after frost;
- soil heterogeneity.
Depending on the level of groundwater, the approach to waterproofing will be different.
The water level is more than one meter below the base of the foundation.
In this case, coating vertical waterproofing and horizontal waterproofing with roofing material are made.
The water level is more than one meter above the base of the foundation.
If the water does not reach the basement, then horizontal waterproofing is done in two layers. These layers are smeared with mastic between themselves. Vertical waterproofing is done both by coating and pasting using rolled materials. It is also possible to treat all elements of the foundation and basement with penetrating waterproofing, which will stop the movement of water through the capillaries.
The water level is above the base of the foundation, as well as the floor in the basement.
If, in addition, the area is famous for heavy rainfall, then in addition to all previous events, drainage will be additionally equipped around the entire perimeter of the house.
Horizontal foundation waterproofing
For a solid (monolithic) or strip foundation, horizontal waterproofing is performed in two places:
- at the junction of the wall and the foundation, and in the basement;
- below the floor level of the basement by 20 cm.
It must be remembered that horizontal waterproofing is performed only at the construction stage of the structure, so it is very important to think about its arrangement in advance.
Before starting work, greasy clay 30 cm thick is poured into the bottom of the pit, which is carefully compacted. A layer of concrete 7 cm thick is poured over it. Such a concrete layer will make it possible to equip waterproofing directly under the foundation.
Before laying the waterproofing, the concrete layer must dry and then settle for a week. After that, the entire concrete area is coated with bituminous mastic, and roofing material is laid on top in one layer.
The surface of the roofing material is coated again with mastic, and the next layer of roofing material is laid on top of it. 7 cm of concrete solution is poured from above, which is leveled and ironed out.
Ironing- This is a necessary measure that will ensure high-quality waterproofing. It is carried out as follows: 2 cm cement is poured over the poured concrete mortar, which was previously sifted through a fine sieve. Backfilling is carried out only after 3 hours after pouring concrete.
Next, the cement mixture is leveled, and after a while it will have to get wet from the moisture contained in the concrete. Further, the resulting surface is periodically moistened with water until the concrete dries and reaches its strength.
Upon completion of the arrangement of the foundation, it is again waterproofed so that moisture does not penetrate the walls in a capillary way. That is why the entire surface is covered with mastic, and roofing material is placed on top of such a layer.
This procedure is performed twice to obtain two layers. The edges of the waterproofing material hanging from the edges of the foundation are not cut off, but lead down and pressed with vertical waterproofing.
Drainage system device
If the depth of laying the foundation is below the groundwater level, and the soil itself has poor permeability, then it is additionally necessary to make drainage. It will allow you to divert groundwater and excess precipitation into a separate well.
First you need to dig a trench around the entire perimeter of the house, 70 cm behind it. The depth of the trench will depend on the depth of the water table. The width of the trench is no more than 40 cm.
All trenches should be located at a slight slope, which is directed towards the pit or collecting well. Geotextiles are laid at the bottom, wrapping its edges onto the sides of the trench. The edges should not be more than 90 cm. On top of the geotextile, we pour crushed stone or gravel 5 cm thick.
Next, we put drainage perforated pipes with a slope of 5 mm per linear meter. The desired slope is achieved by adding gravel. All pipes are covered with washed gravel 30 cm thick. Flushing is necessary in order not to clog the pipes.
By the way, drainage can be done after the completion of the entire construction, as well as some time after it, if necessary.
Foundation vertical waterproofing
Vertical waterproofing refers to the treatment of foundation walls. It can be made in various ways and materials, combining them with each other.
Bituminous waterproofing
This type of waterproofing is the simplest and cheapest. Bituminous resin is used to coat the walls. It is made as follows: bitumen and a large container (bucket, vat, pan) are bought. Bitumen (70%) and used oil (30%) are poured into this container. The whole mixture is heated to a liquid state, and then applied to the foundation wall, which is pre-levelled.
Bituminous resin is applied with a roller or brush very carefully. It is better to start from the sole, moving towards the surface of the soil, not reaching it about 20 cm. You need to apply 3 layers of bituminous resin so that the total thickness is 5 cm. The container with bitumen is heated throughout the entire application time.
Thus, the bitumen will penetrate into the pores of the concrete and fill them, preventing further penetration of moisture into it. The service life of such waterproofing will be 5 years. At the end of its service life, the bituminous resin cracks and collapses, passing all the water through it.
That is why it is worth thinking about extending the life of bituminous waterproofing using bitumen-polymer mastics. They are more durable and devoid of all the disadvantages of pure bitumen.
There are polymer mastics of hot or cold application, as well as solutions that have a liquid or hard consistency. It is recommended to apply such solutions with a spatula, roller, spray or grater. It all depends on the consistency of the applied composition.
Advantages:
- ease of application, so you can easily cope with such work without outside help;
- price;
- availability.
Disadvantages:
- mediocre water resistance, since even high-quality processing cannot provide complete isolation from moisture;
- fragility (after 5 or 10 years of service, you will have to re-process);
- slow processing speed.
Pasting (roll) waterproofing
Roll materials are used both separately and in addition to bituminous waterproofing. The most common material for rolled waterproofing is roofing felt. Before applying it, it is necessary to treat the entire roll with mastic or bituminous primer, as with bituminous waterproofing.
The canvases themselves are heated with a gas burner and applied vertically, taking into account an overlap of 20 cm. This method is called fusing. Before fusing, the edges of the horizontal waterproofing are turned down and pressed, fusing roofing material on top of it.
You can also fix the roofing material with adhesive mastics. From above, the roofing felt is covered with the same mastic and the subsequent roofing material layer is glued onto it.
Advantages:
- low cost of the material;
- durability (up to 50 years);
- availability.
Disadvantages:
- the inability to cope with the work alone;
- one roofing material is not able to provide proper water resistance, so there is a need to use other materials, which negates the cost advantage.
Instead of roofing felt, other roll materials can also be used: Stekloizol, Gidrostekloizol, TechnoNIKOL, Rubitex, Technoelast and others. The basis of all these materials is polyester, which significantly increases wear resistance, elasticity and improves performance.
The only disadvantage of such materials is that they do not provide coating strength if mastic is not used, since they do not penetrate into the pores of concrete.
Waterproofing with liquid rubber
Liquid rubber has excellent adhesion to concrete, and it is also completely fireproof. The treated surface is seamless, which provides high-quality protection against moisture.
The material consumption is about 3 or 3.5 kg per square meter of surface. Usually, two solutions are used for waterproofing with liquid rubber: Elastomiks or Elastopaz.
Elastomics
This solution is applied in one layer, after which it will take about two hours to dry at a temperature of about +15°C. Elastomix is sold in 10 kg buckets. If, as a result of the work, you have an open bucket with Elastomix left, then it is already useless to store it, since the activator-adsorbent added to the mixture immediately before use turns the contents into rubber.
Elastomiks is applied only on a dust-free surface treated with a primer. Only after an hour, liquid rubber is applied with a roller, brush or spatula.
The surface treated with liquid rubber may also require additional protection from external influences if the backfill soil contains debris or stones. In this case, a pressure wall is installed or the foundation itself is covered with geotextiles.
Elastopaz
This solution is applied in two layers, and it will take about a day to dry at a temperature of +20°C. Elastopaz is sold in buckets of 18 kg. Unlike Elastomix, an open bucket of Elastopaz can be reused by sealing the bucket.
Advantages:
- excellent waterproofing;
- additional installation skills are not required;
- durability.
Disadvantages:
- the high cost of the material;
- the material is not sold everywhere;
- without a sprayer, the time spent on the waterproofing process will be noticeably increased.
Penetrating waterproofing
Such waterproofing is made of materials that contain substances that penetrate into the concrete structure by 20 cm and crystallize in it. These hydrophobic crystals prevent the spread of water through the capillaries into the concrete structure. With penetrating waterproofing, the frost resistance of the concrete itself increases, as well as its anti-corrosion properties.
Of the materials used "Hydrotex", "Aquatron" and "Penetron". They differ from each other in the method of application and the depth of penetration. But most often these materials process the internal surfaces of the concrete foundation, basement and basement.
The best thing is to apply the waterproofing material to the wet concrete. But first you need to clean the surface of dust, and then thoroughly moisten. Waterproofing is applied in several layers. After complete absorption of the material, the outer film is removed.
Advantages:
- ease of application;
- durability;
- effective waterproofing;
- the possibility of processing the interior of the building.
Disadvantages:
- price;
- sale of material is not available for all regions.
Plaster waterproofing
Plaster mixtures are indispensable for processing, as well as leveling the foundation surface. Their mixture contains moisture-resistant components: hydroconcrete, polymer concrete and asphalt mastics.
The plastering process is carried out according to the same scheme as the plastering of walls on a lighthouse. To prevent the appearance of cracks, the mixture is recommended to be applied hot. When the plaster layer dries, it is usually protected with a clay lock and clay backfill.
Advantages:
- high speed of work;
- ease of work;
- low material cost.
Disadvantages:
- high probability of cracking;
- low water resistance;
- fragility (less than 15 years).
Screen waterproofing
Screen waterproofing is a replacement for a clay castle. It is used to protect the foundation from pressure waters, which are quite aggressive for concrete. Of the materials used here are concrete mats, which are based on clay. Screen insulation is usually used in conjunction with other types of waterproofing.
Clay mats are attached to the foundation with a construction gun or dowels. The material is laid with an overlap of 15 cm. A pressure wall of concrete is made nearby, which is an obstacle and does not allow the mats to swell.
During operation, the paper component of betonite mats decomposes, and the clay is pressed directly into the very surface of the foundation.
Advantages:
- good waterproofing;
- the possibility of using with other types of waterproofing;
- high degree of waterproofing;
- ease of installation.
Disadvantages:
- high cost of the material;
- possibility of use only for non-residential buildings.
clay castle
Such waterproofing allows you to prevent pressure water from reaching the foundation itself. For its arrangement, a trench 60 cm deep is dug around it. The bottom is covered with a layer of rubble. The wall and bottom of the trench must be rammed with greasy clay in several layers.
After laying each of the layers, a drying break is made. The remaining space of the trench is covered with clay or gravel, but a blind area is equipped on top.
During the flood period, clay will not let water reach the concrete foundation, since all moisture will go into the rubble layer.
Advantages:
- very reliable method of waterproofing;
- low cost of materials;
- availability of materials;
- such waterproofing can be used as an additional to its other types;
- ease of arrangement.
Disadvantages:
- clay castle is used only for wells or small outbuildings.
Choosing the type of foundation
For waterproofing a monolithic slab foundation, it is better to use both vertical and horizontal moisture protection. If at some stage of construction horizontal waterproofing was missed, then in this case it is necessary to perform roll-bitumen waterproofing or waterproofing with liquid rubber.
For a tape type foundation, bituminous, plaster or penetrating waterproofing is preferable.
For a columnar and pile-screw foundation, in addition to the above methods of hydroprotection, additional treatment of the metal elements of the foundation with a special anti-corrosion solution is used.
- The most effective will be the use of a combination of different waterproofing methods.
- Do not save on materials, as repairing the foundation will cost much more.
- Consult with experts about choosing the type of foundation if you are not sure.
- It is worth thinking about the method of waterproofing already at the stage of pouring concrete under the foundation, which will significantly reduce future costs and significantly simplify the whole process.
- If you have chosen bituminous waterproofing, then you can bypass the process of filling small gaps, since bitumen penetrates and seals perfectly.
- With roll waterproofing, roofing material can be applied in several layers in a row, if necessary. Also do not forget to create a bituminous layer between all layers.
Finally, a video of the process of applying penetrating waterproofing:
