There are several varieties of drainage systems. To drain groundwater from the foundations of buildings, ring, wall, and head networks can be used. But on aquifers of great thickness, in most cases, reservoir drainage is equipped.
What is the system
Drainage networks of this type are mounted only at the stage of construction of buildings or structures. A feature of reservoir drainage is, first of all, that it is equipped under the base of the foundation, at the level of the sand cushion.
At the same time, such networks are being built in conjunction with pipe networks. That is, excess moisture in this case is removed from the base of the building by means of perforated highways. It enters a specially equipped receiving well, the nearest stream, pond, etc.
Benefits of reservoir drainage
The main advantage of networks of this type is precisely the fact that they are able to effectively remove water from foundations in cases where other types of systems cannot cope with this task.can.
In addition to the actual groundwater, systems of this variety perfectly protect the foundations of buildings from capillary moisture. It is especially advisable to assemble such a drainage network when building houses with basements on poorly permeable soils.
The disadvantage of this type of diverting systems, in addition to the need for installation at the stage of building construction, is the complexity of the work being done. The cost of reservoir drainage is also usually quite high. It is for this reason that the owners of suburban buildings, in order to protect their foundations, choose such networks only after carefully weighing all the pros and cons.
Net design
When arranging a drainage system of this type, an air gap is provided under the building, which can be made using different technologies. The structural elements of networks of this type, in addition to pipes and wells, are:
- waterproofing layer;
- gravel bed.
In the event that a large influx of water is expected on the site selected for the construction of the house, the reservoir drainage under the foundation slab can be equipped in two layers. At the same time, its lower part is made of sand, and the upper part is made of crushed stone and gravel. Such networks, of course, cost the owner of houses more than usual. But their use in the construction of a building on wet ground can significantly extend the life of the foundation.
Under buildings, the thickness of such drainage is usually at least 300 mm. When building large houses, the calculationthe thickness of the discharge layer of this type can be made separately, with the involvement of specialists.
Mounting Features
Equipment under the building reservoir drainage to protect against groundwater flooding of the foundation, among other things, observe the following rules:
- Under buildings, the thickness of such drainage should be at least 300 mm. When building large houses, the calculation of the thickness of the discharge layer of this type is carried out separately.
- Reservoir drainage to be installed under the building must necessarily go beyond its limits by about 20-30 centimeters.
When using a reservoir system to drain water around the perimeter of the building, in many cases, linear drainage is also equipped.
Main installation steps
Reservoir drainage is usually arranged according to the following scheme:
- at the construction site of the building, a foundation pit is dug under the foundation and deepened by 30 centimeters;
- crushed stone mixed with gravel is poured into the bottom of the pit over its entire area;
- perforated plastic flexible pipes with stiffeners are laid along the perimeter of the layer.
At the next stage, the actual construction of the foundation itself begins, according to standard technology in compliance with the norms of SNiP.
Crushed stone for arranging the air gap under the foundation of the building is supposed to be taken not lime. Otherwise, the material will subsequently be gradually destroyed by water.
When laying on the bottom of the pit, crushed stone must be carefully rammed. Otherwise, the building will subsequently settle unevenly, which can lead to the destruction of its structures. When backfilling the crushed stone layer, a slope is observed in the direction where the receiving well will subsequently be equipped. When using such a system, the waterproofer is laid in the pit with an overlap on the walls.
Receiving wells
Water tanks in the arrangement of reservoir drainage are usually located at a distance of about 1-3 m from the foundation of the building. In this case, deep wells are supposed to be dug. The distance from the entry point of the output pipe to the bottom of such a receiver should not be less than 1 m.
Wells are mounted when arranging reservoir drainage, usually using concrete or plastic rings. The width and depth of the hole under the receiver is chosen in such a way that these elements are subsequently installed freely in it. When using concrete rings around the circumference of the well, a free space of 20-30 cm is left.
Before installing the well, a layer of crushed stone 30 cm thick is poured onto the bottom of the pit. In this case, the drainage material is also carefully rammed. At the final stage of arranging the receiver, the drainage pipes themselves are inserted into the rings. Next, the space between the walls of the well and the pit is filled with crushed stone. When using a receiver of this design, the water coming from under the house is diverted into the soil layers.
Usefultip
Reservoir drainage has a relatively simple design. However, each of its elements will continue to perform a very important function. This applies, of course, including the receiver.
A do-it-yourself concrete or plastic well should not be thoroughly filled up. In order to prevent rain and melt water from entering the container, you just need to cover it with a reliable lid. If the well is covered with earth, it will be difficult to get close to it if it is necessary to clean the pipes or revise it in the future.
Perforated pipes for formation drainage should be laid with an inclination towards the collector of about 2-3 mm per m (for mains with a diameter of 5-10 cm). It is necessary to adhere to such indicators. Otherwise, in the future, the system will work inefficiently or it will begin to clog. Pipes with a diameter greater than 10 cm are laid with a smaller slope.
What mistakes can private developers make
Establishment of reservoir drainage is laborious, but technically not particularly difficult. Nevertheless, when installing such a network, private developers often make mistakes that reduce the effectiveness of its work in the future.
In order for the drainage system to divert all water from the foundation of the building, during its installation it is worth, among other things, to adhere to the following recommendations:
- Do not use geotextiles as a filter for pipes when arranging such a system. After a few years, an interlayer of this type simply becomes clogged, which will lead to a significant decrease in efficiency.network operation. It is especially important to follow this rule if the house is located on a site with sandy or loamy soil.
- When arranging reservoir drainage, the installation of pipes, as already mentioned, is carried out with a slight slope. To position these network elements as accurately as possible, it is worth using a level. When using a normal building level in this case, it will be very easy to make a mistake.
Removal of water from the foundation reservoir drainage is actually very effective. In the event that just such a system is equipped under the building, its service life will increase significantly. But such networks are intended, of course, precisely for the removal of groundwater. At the same time, the foundation itself can be destroyed, including by melt or rain.
Relying only on reservoir drainage in terms of maintaining the integrity of the base of the building is therefore not worth it. When building a house, it is imperative to additionally mount a drainage system with storm drains. When assembling such a network, it must be borne in mind that it is impossible to combine storm water and drainage to the same pipe. Otherwise, the soil in the immediate vicinity of the foundation will be waterlogged. And this, in turn, can cause the destruction of the base of the building as a result of spring heaving.
How to choose the right materials
Pipes for reservoir drainage, in fact, you can take any. But perforated lines made of composite or polymer material are best suited for such a system.
For the wellit is best to use concrete or plastic rings. But if desired, the walls of the receiver can be laid out, for example, with a brick. In this case, only ceramic material should be used. Silicate brick is not suitable for this purpose.
You can also lay a well with a piece of rubber rolled into a pipe, or use any other moisture-proof materials.
Drainage not into the well
If, for example, a stream flows near the house, it is not necessary to equip the receiver on the site. In this case, the pipe can be brought into such a reservoir. The main line to the stream should also be laid with a slope of several millimeters per linear meter.
Drainage lines located under the house, in this case, are connected to the outlet pipe using a tee. The outer line itself should be pulled below the freezing of the soil. Of course, a perforated pipe should also be used for the outlet line. In this case, it would be better to wrap it with geotextile. It will not be difficult to replace this material if necessary in the future. The highway laid in the ground when using geotextiles will be less clogged. Today on sale you can also find pipes wrapped with this material from the beginning.
How to extend the service life
So that the drainage system does not stop performing its functions ahead of time, it must, of course, be operated correctly. Between the foundation of the house and the receiving well above the drainage pipe, for example, should not passno technology. Of course, you can not install any heavy structures in this place. It would be best to break a flower bed or lawn in this place.
The drainage pipes themselves under the house should be washed at least once every 2-3 years under high water pressure. If these rules are neglected, the system will quickly clog in the future. Clearing the blockage formed in such a network, of course, will be quite difficult.
