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Ring and wall foundation drainage. Ring foundation drainage price Drainage structures and drainage filters

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Description

Types and types of drainage

In areas with high groundwater levels, it is customary to drain the supporting soil before constructing foundations.

Moreover, the installation of foundation drainage involves performing a whole complex of rather labor-intensive operations, the success of which determines the very possibility of constructing a residential or industrial facility.

Types and types of drainage

Modern drainage can be of two types:

  1. Perfect type drainage. It is made on waterproof water. Water enters this type of drainage from the top and sides. This means that this type should be sprinkled on top and sides.
  2. Drainage of imperfect type. It is made above the waterproof level. Water enters it from above, below and from the side, which means that such a foundation must be sprinkled on all sides.

OPEN DRAINAGE DEVICE

Surface, open drainage is a system of ditches of various sizes, tree-shaped. Everyone has a rough idea of ​​how to make this kind of drainage. To create it, all you need from tools is a shovel and a wheelbarrow.

The largest - the central ditch - serves as an exit channel. Adjacent to it are smaller side “branches” into which smaller grooves “flow”. It is better to place them at right angles to each other. Often the grooves are filled with crushed stone, sand or other material that allows water to pass through well, and covered with turf or mesh. This type of drainage is called reservoir drainage. The slope of the canal should be about 3 cm per m.

If there are many areas of accumulation and stagnation of water on the site, you can make parallel ditches (for example, along paths or near a pool). Cleaning large areas of water is called linear. If you have one or two places where a large amount of water gets in, it is enough to make local, or point, drainage. For example, to drain water coming from a storm gutter in front of the terrace or at the entrance.

If your site is exposed exclusively to external “attacks”, that is, water flows onto it from neighboring areas, you can use open drainage, limiting yourself to ditches near the fence that prevent water penetration.

At first glance, this type of drainage system is quite simple. However, there are some pitfalls here. This system is suitable for places with a natural slope, and also requires careful organization of the site. It is necessary to level it thoroughly, filling in all the depressions and depressions and leveling the hills and elevations that can organize the reverse flow of water.

DEEP DRAINAGE SYSTEM

Deep closed, or tubular, drainage is most common these days. It is used in densely built-up areas where it is not possible to build an open system, in places where there is no natural slope, in areas with an extensive system of paths, in gardens with complex landscape design using numerous plant species.

A deep tubular system is a linear type of drainage; its point use is rare. Drains can be made from asbestos-cement, ceramic or plastic perforated pipes. Their diameter is 8-11 cm and above. Smaller diameter pipes are not suitable for these purposes.

If for some reason it is not possible to buy perforated pipes, you can use ordinary plastic pipes for external sewerage. To do this, make cuts on them in a checkerboard pattern for half the diameter of the pipe. The distance between the slots is no more than 50 cm. Or drill 5 mm holes on all sides, the distance between which will be about 1 cm.

Deep drainage begins with digging trenches according to a previously drawn up project. In garden plots, a system of canals forms a kind of Christmas tree. It is necessary to make ring drainage around the house.

The depth of the trenches depends on the degree of your problem and varies from 50 cm to 3 m. It is better to lay pipes below the freezing level of the soil - 110-130 cm. Near the house below the foundation level. To drain water from the root systems of trees, drains are deepened by more than 1.5 m. The distance between drainage trenches on the site is 5-10 m. When calculating the depth, 20 cm should be added to the required dimensions for the installation of a “cushion”. The slope of the trench bottom is made towards the collector (0.5-1 cm - near the house and up to 3 cm per m - on the site).

WHY ARE WELLS NEEDED?

At every 90° turn, inspection wells are installed (sometimes, to save money, they are made at every second corner).

On straight sections they are installed every 50 meters.

They are made from large diameter pipes. You can also find ready-made prefabricated wells on the market.

To do this, the drainage pipe is fixed at a level of 20 cm above the bottom of the well.

When there is quite a lot of sludge, it is removed with a special pump. The pump is lowered into the well, then, after agitating the water at the bottom with a pressure jet, it is turned on.

Foundation ring drainage

Ring drainage is an excellent solution to eliminate the problem when groundwater and rainwater seep into the soil next to the foundation wall, have a destructive effect on it, and also penetrate into the basement.

Most often, this problem manifests itself during spring floods, when the snow melts and the soil thaws. This disturbs the peace of the house's residents, forcing them to pump out water from the basement. Ring drainage is a network of perforated pipes suitably laid around foundations and draining groundwater accumulating in this place.

What is important to consider when choosing this type of drainage:

  • the action of such drainage implies a ring, the inside of which will be isolated from water;
  • if water comes from one specific side, then such drainage can be laid in the form of an open circle;
  • such a system is installed below the floor level of the basement room that must be protected from moisture;
  • Such a system should be laid at a distance of 5-8 meters from the wall itself. If this distance is less, then care must be taken to remove, weaken or settle the soil of the building itself.

Wall foundation drainage

Today, one of the most effective is the drainage of the foundation of a wall-type house. This type of drainage removes water from the base and protects against the extreme rise of moisture contained in the soil. As a result, the durability of the building increases; there are no puddles, fungus, mold and other destructive organisms in the basements.

A wall drain is a structure typically constructed below the basement floor level. A foundation drainage system is especially necessary if the house has a basement or ground floor. And it is advisable to take care of it at the initial stage of construction - at the stage of laying the foundation pit.

If drainage was not provided for during the design, then the existing house will have to be protected from groundwater. And you should start by digging a pit around the house again.

Drainage pipes are installed around the perimeter of the house. In the places where they connect, in the corners, inspection wells are installed. At the lowest point of the site there is a pumping well. It must discharge excess water off-site into a storm drain or a nearby body of water. In order to properly drain the foundation, a number of components should be taken into account. The depth at which the foundation is laid.

Regardless of the material used to organize water drainage, the entire drainage system is laid 30-50 cm below the location of the base cushion. The slope should also be taken into account. Lowering the drainage system towards the collecting collector at an angle with a coefficient of 0.02 (2 cm per 1 m) will ensure uninterrupted drainage of excess water and prevent it from stagnating in the pipes. Remember that in any case, the drainage of the foundation slab should be located no closer than 3 m from the house. It is also necessary to provide for a concrete blind area, which should extend at least 1 m from the foundation of the building.

What is important to know when choosing this type:

  • It is often used as a preventative against water;
  • This drainage system is often used with a mixed source of groundwater;
  • Such drainage is laid outside the building. The distance from the wall to the drainage system is equal to the width of the foundation of the building itself.
  • Such a system is laid no lower than the level of the base of the foundation;
  • If the foundation depth is too deep, the drainage may be slightly higher.

Reservoir foundation drainage

Reservoir drainage is an air gap that is made using different methods.

For example, one of the most common options is to install a gravel layer. In this case, a layer of gravel up to 50 cm is placed directly under the surface being used.

This layer is the air gap. The second layer is a filter fabric (geotextile). Afterwards, a layer of sand is poured and finishing material, for example, tiles, is laid.

Note! One of the main advantages of this type of drainage is the availability of building material.

This type of drainage is usually used in combination with ring or wall drainage. What is important to know when choosing such a system:

  • It is advisable to use such a system when there is a large amount of groundwater on any type of soil;
  • placed for prevention in clay and loamy soil;
  • To interact such a system with external drainage, special pipes are laid through the entire foundation of the building.

So, if reservoir drainage is installed under a building, then it must necessarily extend beyond its boundaries. It eventually connects to the wall drain. If the area is large, then additional drains are laid from pipes directly into the floor of the room. Before arranging it, it is important to think about the threat of flooding by groundwater. Linear drainage can be made around the perimeter, especially if the soil is loamy or clayey.

Horizontal reservoir drainage on concrete

When reservoir drainage is made in sandy soil, in soil with a layered structure, clayey or loamy with a filtration coefficient of 5 m/day, then an inclined or vertical prism of sand with the required filtration coefficient is poured on both sides of the channel. A sand prism is necessary to receive flowing water from the sides.

The main difference, of course, between a ring drain and a wall drain is that it is located directly next to the foundation itself. A roundabout - at a distance of up to 3 meters from the foundation. Otherwise, in principle, they are similar.

What is ring drainage?

A building, or a group of buildings, built on sandy or water-saturated loamy soils must be equipped with a “ring drainage” drainage system. If the building under construction is supposed to have very deep basements, and the general drainage system cannot provide drainage from such depths, then a ring drainage should also be laid.

Sandy soils are characterized by increased water permeability, so ring drainage can be made one for several buildings. If the topography is characterized by a directed flow of groundwater, an open ring drainage can be made. Its design is similar to that of a head drainage device. The depth of the ring drainage should be below the floor of the basement of the building. In large areas or in places with increased requirements for groundwater drainage, calculation of the depth of the ring drainage should ensure that groundwater does not rise above the water level in the head collector of the entire drainage system. If it is impossible to make the required depth of the ring drainage, then laying additional drains and cuts is allowed. The principle of their laying is exactly the same as that of laying system tubular channels and drainages.

Drainage of the site will be reliable if the distance between the building wall and the ring drainage circuit is within 5 -8 meters. Otherwise, the foundation drainage will be insufficient, which will certainly lead to shrinkage of the building. All calculations of any drainage systems are made based on research data from geologists and soil scientists.

Heavy seasonal precipitation and the proximity of aquifers to the ground surface force owners of cottages and country houses to think about combating excess moisture. Its excess can spell serious trouble:
soils oversaturated with moisture become limp, which complicates work and creates difficulties for moving around the site;
due to hydrostatic pressure, moisture intensively penetrates into the pores of the foundation and other building structures, which leads to their partial destruction and reduced reliability, flooding of the basement floors, and deterioration of the indoor microclimate;
During the off-season period, when the air temperature drops below zero degrees at night, the moisture accumulated on the surface of the blind area and steps freezes and turns into ice - which not only contributes to the accelerated destruction of coatings, but most importantly can lead to injuries to people.
water that is not drained from the surface in the autumn-spring period hardens into an impenetrable crust in the upper fertile layer, which not only has a detrimental effect on the lawn and garden plants, but also contributes to the formation of the so-called perched water - water that forms on the surface of the soil, but is not able to percolate into the ground due to a layer of ice. Such waters disappear only after the top layer of the surface has completely thawed; in some cases, the soil does not thaw until the end of May.
The most effective method of control is the installation of a drainage system.

Main tasks of drainage

In the modern understanding, drainage implies the removal of water from the surface or the drainage of groundwater on land plots.
The tasks that the drainage system solves are:
protection of buildings and structures, parts of structures from constant exposure to moisture;
preventing moisture penetration into residential and utility rooms;
ensuring the normal condition of sites and paths;
protection of planted plants from siltation;
elimination of the phenomenon of water erosion of the upper fertile layers.
The first 3 of them are solved by wall or ring drainage at home.

What is ring foundation drainage and its difference from wall drainage?

Wall systems are highly efficient and allow for maximum protection of foundations and basements of buildings. They are installed, as a rule, during the construction of a house at the stage of laying buried structures (primarily foundations). Their main feature is their location in close proximity (at a distance of no more than 1 m) to foundations and walls. Most often they are designed in conjunction with waterproofing systems.

When the house has already been built and the construction of a wall drainage system is difficult or impossible, the best solution is ring drainage of the foundation.

This term refers to a trench system in which drains are laid along the entire perimeter of the building at a certain distance (from 1 to 3 m) from the foundation structures.
This design determines the main features of foundation ring drainage systems:
Ease of implementation - the system can be built on its own without the involvement of construction equipment and the use of expensive materials and components;
Specifics of application - ring drainage around the house in soils with high water permeability (for example, sandstones) is most often used;
Mandatory installation requirements - the system is effective only if the conditions for laying depth, etc. are met.

Basic conditions for ring foundation drainage

To reliably protect foundation structures from moisture and basement rooms from flooding, when laying a ring drainage around the house, it is necessary to fulfill the following conditions:
Lowering the groundwater level within the serviced perimeter. It is determined by the depth of the drains, the height of the groundwater level and the height of the capillary rise of moisture in the soil. In practice, foundation ring drainage pipes are located slightly below the calculated reduced groundwater level, and, as a rule, below the base of the building.
Ensuring an effective drainage radius. It determines the permissible distance from the structures to the axis of the drains and depends on the nature of the soil, the size of the foundation, the depth of the drainage pipes and the width of the trench. It should be remembered that laying at a distance less than the calculated one can lead to leaching of soil from under the foundations, and at a greater distance - to a decrease in the efficiency of groundwater drainage.
The functioning of the system taking into account the climatic characteristics of the area. From this point, foundation ring drainage pipes are produced below the soil freezing level typical for the region.

In addition to these, there are other additional requirements, for example, those determined by sanitary rules, which must also be taken into account when designing the system.

Ring drainage device

Ring foundation drainage is a system of buried perforated pipes (drains) laid along the perimeter of the protected building, usually parallel to the foundation structures.

When designing and installing it, the following should be provided:
The movement of liquid through drains is by gravity, which requires laying them with a slope of 2-5 mm per linear meter of the main line.
Connecting the branches of the system in such a way as to eliminate the danger of blockages and provide for the possibility of cleaning the pipes - as a rule, inspection wells (sections of a vertical pipe covered with covers) are installed in places where drains turn.
A drainage line for discharging the liquid collected by the system into a drainage well, natural reservoirs, sewer system collector or other special hydraulic structures.

How to build a ring drainage system at home

The construction of a ring foundation drainage should begin by determining the characteristics of the site. For design, you will need information about groundwater levels and their seasonal rise, the distribution of precipitation in the region, the nature and level of soil freezing, and topography.

In addition, a diagram of the site and adjacent territories is required, indicating the location of neighboring sites, natural reservoirs and springs, sewers and other hydraulic structures (for example, drainage canals), roads and ditches, etc.
It is difficult to obtain all the necessary information on your own; you will have to turn to specialists from a land management organization or hydrogeologists.
Next, a project (plan) of a foundation ring drainage system is drawn up, indicating the places for laying pipes, installing wells, and pipelines for discharging collected moisture.

Based on it, construction begins:

Trenches are dug to a depth corresponding to the estimated depth of the house drainage system pipes and the thickness of the cushion (the trench width is up to 0.5 m; for drainage efficiency and ease of installation, the trench slopes must have an angle of at least 30 degrees).

In places where the direction of pipes changes, wells are installed (the height must correspond to the blind area).

A cushion is placed at the bottom of the trench - a layer of compacted sand and/or coarse crushed stone up to 15 cm thick.

The rock layer is covered with geotextiles with high water permeability, leaving wings on the slopes of the trenches.

A layer of drainage rocks (washed crushed stone, expanded clay, gravel) is laid on the geotextile, and drains (PVC, polyethylene corrugated or metal perforated pipes) are laid.

Cover the pipes with a layer of drainage material.

The structure is covered with geotextile wings and backfilled with sand or crushed stone and backfilled with soil.

Cost of foundation ring drainage

The costs of constructing a ring foundation drainage system consist of the cost of purchasing materials, the cost of excavation and installation work (if they are carried out by contractors). When constructing a ring drainage around a house on your own, you will have to spend about 600-900 rubles per linear meter of construction. Additional costs will be required for hydrogeological analysis of the site, system design, etc.

Specialized construction organizations offer such services at a price of 1,000 to 3,000 rubles per linear meter (the cost of work increases especially significantly with increasing laying depth).

A particularly advantageous option would be to conclude an agreement with an organization that can undertake all types of work - from analysis and design to commissioning, such as Promstok. In this case, fulfillment of all requirements, including those determined by federal and local legislation, and high quality of materials and work are guaranteed.

In a private house there are several places that need to be protected from getting wet from the outside. These are the foundation and buried buildings. Rainwater, all kinds of drains and rising groundwater gradually destroy the monolithic foundations and walls of basements. A properly equipped drainage system around the house can prevent this process from occurring. It is capable of removing excess moisture from structures. Even a very good blind area cannot compare in terms of protection for a house with a installed drainage system. It is highly recommended to install such a system near every house, regardless of the presence of a basement or ground floor.

A high-quality drainage system around the house with your own hands can be made in several options:

Features of different foundation drainage systems

The choice of a specific type of drainage depends on the presence of buried rooms, the depth of groundwater, the composition of the soil on the site and the topography of the site itself. Let's consider what features the drainage system around the house has.

In total, there are 3 types of drainage, which differ in their location and design:


Important: Please note that reservoir drainage does not replace another type of drainage, but only complements it. Therefore, in addition to it, a main drainage system must be installed.

Please note that if you decide to make a ring drainage around the house with your own hands, the system should be located 0.5 m below the foundation level. This arrangement will ensure high-quality drainage of groundwater from the building at any time of the year.

And if you are thinking about this, then you may find our separate material on this topic useful.

Drainage installation

Let's look at how to make a drainage system around the house in two ways.

Manufacturing of wall drainage

Before carrying out the work, it is necessary to prepare the foundation, since the system will be directly adjacent to it.

To do this, the following work is carried out:

  1. The foundation from the outside is primed with a special bitumen primer.
  2. Bitumen mastic is applied to the dried surface.
  3. A reinforcing mesh with 2 x 2 mm cells is glued onto the mastic.
  4. The next day, after the mastic has hardened, a second layer of mastic is again applied to the mesh.

 The photo shows the drainage system around the house - a trench and inspection wells along the edges
  • A collector well is installed to which drainage pipes will be connected. It is located at the lowest point on the site;
  • using a laser or building level, the slope of the trench running near the foundation is ensured towards the drainage basin;
  • the bottom of the trenches is covered with a layer of sand of at least 5 cm;
  • geotextiles are laid on the sand, the sides of which will subsequently be wrapped overlapping;
  • a gravel backfill is created having a thickness of about 10 cm;
  • Prepared perforated pipes are laid on the gravel layer. Their slope is ensured at 2 degrees;
  • pipes are joined with adapters and corner connectors;
  • at the corners of the building, all pipelines enter installed inspection wells;
  • Pipes are laid from inspection wells to drain water into a collection well or drainage pit. These pipes are also located in trenches and have a slope;
  • The pipes are filled with gravel (about 10 cm) and the entire contents are wrapped in geotextiles. Using synthetic ropes, geotextiles are firmly fixed;
  • further backfilling of the trenches to the soil level is carried out with sand or turf soil.

We looked at how to make drainage around a wall-type foundation. Next, we will pay attention to the manufacture of trench drainage, which is even more popular.

Manufacturing of ring drainage

For this type of work you will also need perforated pipes, crushed stone, sand and geotextiles. When a ring drainage system is made around a house, the technology involves digging trenches at a distance of 5-8 m from the foundation of the building to eliminate the possibility of subsidence of the soil around it. The trenches are located around the structure and form a closed system. The depth of the trenches should be such that the drainage passes 50 cm below the foundation level.

Immediately draw a trench (or several trenches) towards the main drainage well. The slope of the trenches is ensured at least 2-3 cm per linear meter. The slope can be adjusted by adding sand in the right places.
  • the bottom of the trenches is lined with a layer of sand, and then with geotextiles, the edges of which are wrapped on their walls;
  • crushed stone is poured onto the geotextile in a layer of 10 cm;
  • Pipes with holes drilled in them are laid out on the crushed stone. It is advisable to use a pipe diameter of at least 10 cm. It is advisable to first wrap all pipes with a layer of geotextile, which will prevent them from clogging;

Tip: Regular PVC pipes used for sewerage are quite suitable. You can drill holes of small diameter in them with a drill, arranging them in a certain order.

  • the slope of the pipes is checked, which must be at least 2 degrees;
  • At pipe bends, inspection wells are installed, covered with removable covers. The same wells should be installed on long straight sections, in increments of 12 m;
  • crushed stone or gravel is poured over the laid pipes in a layer of 20-30 cm;
  • the entire “pie” inside the trenches is wrapped with geotextile overlapping;
  • the remaining space in the trenches is filled with river sand and covered with turf.

Features of drainage wells

Any drainage around a site or building must be constructed using several inspection wells located at pipe bends. It is in these places that drainage pipes become clogged most often. Through the inspection well, you can monitor the cleanliness of the drains and clean them if necessary. Wells can be purchased or made from any materials. They should have such a width that it is convenient to clean them by placing your hand there.


In addition to several inspection wells, at the lowest point of the site there is collector well, designed to collect all the water flowing through the channels. This is a wider and more voluminous structure, which can be concrete, plastic or metal. Its depth is chosen so that the pipes entering it are located at a considerable distance from the bottom. This makes it possible to periodically clean the well from sediments accumulated at its bottom and allows the well to fill with wastewater. From the collection tank, water can be pumped out by a pump or flow by gravity to designated areas.

By creating a drainage system around the house according to all the rules, you will get rid of the harmful effects of excessive dampness affecting the foundation and recessed areas of the house.

When building a private house, the problem of draining groundwater from the foundation often arises. This is very important when their level is high and the base of the soil is clay or loam. This is also of great importance if the house has a basement or basement. If you do not drain the foundation of the building, the basement will always be damp, the walls will become covered with mold, and the floor may also be flooded with groundwater.

Water negatively affects the durability and strength of concrete structures of the foundation of a house, regardless of the quality and composition of the waterproofing. The foundation drainage scheme is developed at the design stage and is carried out together with the construction of the foundation, which allows saving on excavation work.

Main types of drainage system

Based on their functional purpose and installation method, there are several main types of drainage around the foundation of a house:

  • surface drainage - acts as a storm drain around the house, closely connected with the roof drainage system;
  • wall foundation drainage;
  • foundation ring drainage;
  • reservoir drainage.

Each type has its own characteristics and purpose. Often, several types of drainage are performed simultaneously, with surface drainage removing rainwater from the roof of a building, and wall drainage draining groundwater from the base of the foundation.

Photo from the site during drainage installation.

Ring drainage is often used in the construction of private houses in areas with high groundwater levels. It consists of perforated drainage pipes laid along the perimeter of the house foundation and inspection wells.

Such a drainage system can be around any foundation - slab, strip, columnar. This system ends with a common drainage well into which all waste water is discharged. Water is drained from it by a sewer pipe towards the street or ravine.

The difference between wall and ring drainage is the distance of its installation from the surface of the foundation. For ring drainage this is an average of three meters, and wall drainage is installed at a distance of about one meter.

Reservoir drainage is performed under the entire area of ​​the building and can be used with slab and strip foundations. It is often used in the construction of baths.

There is a so-called system. foundation drainage light, used to protect basements from groundwater in clay soils. It is usually used for unused basements.

Materials and tools

To install foundation drainage, you will need the following materials, which must be purchased in advance, taking into account the draft:

  • perforated plastic pipe;
  • geotextiles;
  • inspection wells;
  • sand;
  • crushed stone

If necessary, you can use available materials to construct inspection wells.

Film for waterproofing.

In addition to materials for high-quality installation, you will need the necessary tools:

  • shovels and bayonet shovels;
  • jackhammer;
  • wheelbarrow for transporting soil and crushed stone;
  • laser or regular level;
  • tape measure and pegs;
  • cord;
  • grinder for cutting pipes;
  • knife for cutting geotextiles.

All work on installing a ring drainage system around the house does not present much difficulty in its implementation and can be done with your own hands, without the involvement of specialists. However, design documentation, which stipulates the need for a drainage system, must be ordered from specialized design organizations that can assess the composition of the soil in the selected area.

Drainage device

A common type of drainage system for the foundation of a house is ring drainage. It is better to carry it out in parallel with the construction of the foundation of the house. Let us consider step by step the entire process of installing such a system. Waterproofing must be done before drainage can be carried out. All work can be divided into the following stages:

  • preparing a trench around the house to the depth of the foundation, its width can be any, but not less than 50 cm, while the bottom is made with a slope of approximately 2 cm per meter;
  • backfilling the underlying cushion with sand 150 - 200 mm thick;
  • installation of inspection and drainage wells in the corners of the building; holes must first be made in their walls;
  • laying geotextiles up to two meters wide at the bottom of the trench;
  • installing a layer of medium-fraction crushed stone at the bottom of the trench on top of geotextiles, this layer should be up to 20 cm thick;
  • laying perforated pipes with a slope;
  • filling the pipes with crushed stone in a layer of approximately 30 - 40 cm;
  • wrapping pipes covered with crushed stone, geotextiles with an overlap;
  • backfilling the trench with soil to the level of the blind area.

Foundation drainage can be done with your own hands without the involvement of specialists. The considered option relates to the installation of deep drainage to combat groundwater. Using the same technology, surface drainage can be made, acting as a storm drain, collecting and draining rainwater from the roof and from the local area.

Let us consider in more detail the design of deep drainage for the foundation of a building. This type is suitable for a strip foundation of a house. Ring drainage, like wall drainage around the foundation, can be carried out both after the construction of the house, and in parallel with the construction of the foundation, which is much preferable.

The depth of drainage varies, but it mainly depends on the depth of the foundation. It is optimal when the drainage pipes are at the level of the lower plane of the strip foundation.

To correctly design a slope, it is best to use a laser or optical level, setting a slope of 2 cm per linear meter. The mark of the trench can be easily determined by knowing the depth of the drainage pipe - it is approximately equal to the depth of the foundation. In this case, the trench is deepened 300 mm lower - for the installation of a sand cushion and crushed stone backfill.

After laying the pipes and connecting them to the inspection wells, the slope is finally checked, and, if necessary, backfilling or recessing is done - this is the most important stage of the entire work. The slope is checked throughout the drainage system: between inspection wells, between the ring drainage and the last well, as well as the exit from it to the street well or ravine. Everywhere there must be a slope of at least 2 cm per meter.

Wall drainage.

The next stage is filling the pipes with a layer of crushed stone and wrapping this “pie” with geotextile so that the fabric overlaps. All that remains is to backfill - it can be done with sand or soil previously removed from the trench.