How to make drainage under the foundation. How to make foundation drainage around the house with your own hands, projects. Main types of drainage for foundations

The fact that the foundation of any structure bears maximum loads does not make this structure invulnerable to external factors. Regardless of the type of base and degree of waterproofing, the foundation is very sensitive to moisture attacks. Its natural enemies: groundwater, high water, and precipitation - under certain conditions, all this negatively affects the freezing and thawing cycles of the foundation material and its resistance to corrosion. To remove excess moisture from the base of the building, a simple but effective solution is used - a foundation drainage device.

When is foundation drainage appropriate?

The main difficulties with draining water from the base of a building appear in places where the site has water-resistant soil that prevents the natural filtration of liquid from top to bottom. As a rule, it is clay, loam, sandy loam. Another threat comes from groundwater when it is too high. This may be due to the terrain features of the site - its location in a lowland. Over-moistened heaving soil is also subject to changes in volume during freezing and thawing: the impact can be so great that the safety of the entire building is threatened. Drainage around the foundation in such cases is necessary, because sometimes only it can ensure safety from water for basements, as well as elements of the foundation itself. The main task when installing drainage is to collect excess moisture around the perimeter of the base of the house and direct it in the right direction.

Composition of the foundation drainage system

Drainage is a set of special perforated pipes dug around the perimeter of the building, drainage wells and a collector. Drainage pipes are used to collect and drain liquid from soil layers that enters the plane of the pipeline system. The movement of water in them is ensured by artificially setting a slope towards the collector well. From the latter, liquid is forcibly removed using a submersible pump - it can be used for irrigation. Every second turn of the pipeline system is equipped with a drainage well, which is used as an inspection and sludge tank. As sludge accumulates, it is pumped out with a special pump; if necessary, silted drains are cleared with a powerful stream of water.

Carrying out work on foundation drainage

As a rule, when building a new house, the installation of a drainage system is immediately provided, because... It is much easier to carry out this work precisely at the stage of foundation construction. If the house is built, then you will have to lay trenches around the perimeter of the building, taking the low and high points of the drainage system. The depth of the trenches is determined based on the depth at which the base of the foundation is located. After the formation of the crushed stone and sand cushion, the drainage pipes should be located below the base of the house. They are laid with a slope of 5-10 mm per meter. Crushed stone is poured around the pipes in a layer of at least 20 cm. To ensure that silting of the crushed stone occurs more slowly, a layer of geotextile is laid before filling it. At every second turn of the pipeline, drainage wells with a diameter of at least 315 mm are installed. From the “lower” (last) well, pipes are laid to a collector well (a waterproof container made of plastic, metal or reinforced concrete rings), which serves as a collector for the discharged liquid. Water is forcibly removed from it using a pump that turns on automatically due to the float level. This is what the drainage arrangement around the foundation looks like in a nutshell.

Are there situations where, to protect foundation drainage not needed?

Water can destroy any organic structure. The foundation of a house is no exception to the rule. Flooding of a plot of land around the foundation or the basement of a building may cause changes that are dangerous to the structure of the building:

Reducing the bearing capacity of the foundation;
Complete destruction of the foundation of the house;
Capillary saturation with moisture of the walls of the first floor of the building;
Flooding of the basement;
The failure of their building maintenance systems located on the ground floor.

Therefore, the construction of a drainage system is necessary for the normal functioning of any facility.

To protect a building from the destructive effects of groundwater, melt or rainwater, specialists use foundation drainage. First, you need to familiarize yourself with a brief description of the types of water that destroy the foundation:

Water resulting from precipitation, seasonal snow melting, or flooding. It is not capable of causing serious damage to the foundation of the house. Removed using storm sewer or point drainage system;
Water found in layers of the earth. Its impact on the foundation leads to complete destruction of the structure. There are several types of groundwater:

Groundwater. Characterized by seasonal changes in level. More dangerous in the spring when the snow melts;
Water in the lenses. Appears when a material capable of absorbing a large volume of liquid is laid on a layer of waterproof base. For example, a sand cushion on a layer of clay;
Water in a sand bed. It is formed when pouring monolithic foundation slabs, in the absence of a gravel layer. The underlying sand cushion becomes saturated with groundwater and the foundation begins to get wet.

Types and device drainage under the foundation

How rule, to prevent flooding and destruction of the foundation by groundwater, several drainage systems are used:

Reservoir outlet. This is a comprehensive protection system consisting of both ring drainage and drainage from the base of the foundation.
Wall outlet. Typically used as strip foundation drainage. It consists of laying pipes along the entire perimeter of the foundation, at a short distance from the base.
Ring outlet. Allows you to protect large areas from groundwater. Suitable for protecting not only the foundation, but the entire site.
Point outlet. Used for local collection of rain and groundwater.

Let's see how drain the foundation with reservoir water drainage

This method of drainage is used in difficult conditions, in combination with other options. Its use is relevant: in the presence of a large volume of retaining water; when placing a water lens directly above a building; with low efficiency of other methods of drainage.

It is often used as a preventive measure against flooding of basements on clay and loamy bases.

Filling the pit with sand. A sand cushion 250–300 mm thick is poured over the entire base area. It is important to fill cavities beyond the boundary of the foundation slab. This is done for the subsequent connection of the reservoir and wall drainages.
Installation of “inserts” made of crushed stone or gravel. They cut through the sand cushion in increments of 6 - 8 m. The depth of crushed stone backfill is 200 mm.

If necessary (due to too intense flooding), reservoir drainage is arranged in 2 layers. The first is a sand cushion with a thickness of 250 - 300 mm. The second is a gravel cushion with a thickness of 200 - 250 mm.

Protection of reservoir drainage from pouring concrete and mortar. Before pouring the concrete base, the entire area is covered with water-repellent material. Otherwise, the concrete may fill all drainage pores. In this case, the efficiency of the drainage structure will deteriorate.

Important! Reservoir drainage does not drain water on its own. It accumulates it in the thickness of sand and rubble. To drain groundwater under a sand cushion, you can lay mine additional row of drainage pipes. If the foundation area is small, then the construction of a wall tubular drainage connected to a reservoir drainage is sufficient. All practical information on issues how to make drainage can be found in numerous video, posted on the pages of Internet portals.

Wall-mounted DIY foundation drainage

This The technology makes it possible to locally lower the groundwater level. The basements will remain dry, the foundation of the house will not collapse, made cosmetic repairs will not be affected. Pipes are installed along the entire perimeter of the house at a distance of no more than 1000 mm from the external walls. The depth is just below the base of the foundation.

Important! Foundation drainage diagram, made using any of the technologies, implies the installation of high-quality waterproofing. As well as insulation of the basement floor. Otherwise, dampness may appear even if there is a reliable drainage system.

Sand cushion installation. The trenches along all the walls of the building are covered with a layer of sand. To create a natural slope, a level or hydraulic level is used. This is important, if you do not make a slope for groundwater flow into the receiving well, then the drainage system will turn out to be a useless structure.
Laying permeable fabric. Geotextiles are usually used; they cover the entire area of the sand cushion. This helps prevent the sand cushion from spreading and eroding.
Filling the first layer of crushed stone. It is laid on top of geotextiles. Furrows are made for the installation of plastic drainage pipes.
Pipe laying. For the construction of a wall drainage system, plastic sewer pipes with a diameter of 100 - 150 mm are used. Holes are drilled in them in advance through which groundwater will flow into the collection well.

Important! The pipe system should be built with a minimum slope of 20 mm per 3 – 4 m of pipe

Connecting individual pipes into a single system. For this, additional elements in the form of doubles and tees are used. It is easier to insert the pipes into each other if you coat the ends with soap. Using a hydraulic level, you must carefully monitor the overall slope of the system.

Important! Vertical inspection wells must be installed at the junction of two pipes at an angle. If the system becomes clogged, it will be possible to remove the blockage through them, restoring the operation of the wall drainage.

Insulation of drainage pipes. After installation is completed, the entire system is wrapped with geotextile and synthetic rope. This is done to protect the holes in the pipes from clogging with crushed stone or gravel particles.
Filling the second layer of crushed stone. The drainage system is covered with a layer of gravel 150 - 200 mm thick. A layer of geotextile is laid on top.
Final sand backfill. The last stage of work on the construction of the wall drainage system of the foundation.

The main sewer pipe, which collects all the drainage branches, may freeze. The reason is its possible shallow location. Therefore, the pipe must be insulated.

Ring drainage of house foundation

Its structure is similar to the wall drainage method, but it is performed for other reasons:

When an already built house needs to be equipped with a drainage system;
When the house does not have a basement;
When a residential property or a group of them is built on a sandy or sandy loam foundation that drains groundwater well;
When other types of drainage systems fail to cope during peak periods of flooding.

The ring drainage system should be built at a distance of 3 m or more from the external walls of the building. There is a dependence: the more sand in the soil, the further the pipes are located from the house. The more clay there is in the soil, the closer they are placed.

Digging a trench. It is made 400 - 500 mm deep below the lowest point of the foundation.
Preparing the base. It is filled with sand (layer 100 - 150 mm), gravel (layer 100 - 150 mm) or geotextiles are laid.
Installation of drainage pipes. Perforated pipes are laid on the prepared base and connected to each other. Their diameter is 100 - 150 mm.

Important! A slope of 20 mm should be observed for every 2 - 3 m of pipe length.

Insulation of pipes with geotextiles. It is tightly wrapped around each section of the ring drainage system. Then the winding is secured with a nylon cord.
Installation of inspection wells. Vertical wells are installed at the junction points at the angle of the drainage pipes. They are needed to clean the entire system from possible blockages.
Backfilling the trench. After all installation work is completed, the trench is filled with sand or gravel. It all depends on the financial condition of the customer.

A ring drainage system can work in conjunction with other drainage options. You can always watch a training video on how to properly make a ring drainage for the foundation.

Point drainage system

Helps collect rainwater from house roofs, auxiliary buildings, paths and sidewalks. Performed in the form:

Storm water inlets. These are plastic tanks for collecting water from roofs. Connected to storm sewer;
Drain drains. Small plastic containers installed along the paths, covered with bars and connected to the storm drain.

House foundation drainage system

One of the options for protecting the foundation of a house from moisture is installing drainage. How to do it yourself - technology for doing the work.

The proximity of groundwater or significant accumulation of moisture in the soil negatively affects buildings, especially the foundation. To eliminate excess moisture, you need to take a number of actions related to the installation of a drainage system.

Here are the main reasons why a building requires foundation drainage:

when the basement is located below the groundwater level or less than 50 cm to it;
if the house is built on clay soil;
if the place where the building stands is an area of capillary moisture.

Foundation ring drainage

If it is necessary to protect a structure (foundation) that does not have a basement floor or a building that is erected on heaving soils from water, then ring drainage is used. As a rule, it is performed at a distance of 0.8 to 3 meters from the foundation walls, behind the blind area.

The foundation drainage system is based on tubular drains, which are installed along the contour of the supporting structure. The principle of operation of the device is to reduce the groundwater level in the protected circuit, thereby significantly reducing the risk of flooding of underground buildings.

The depth to which the drains will be laid in relation to groundwater depends on how much their level will decrease. Considering the fact that the laying of ring pipes is carried out at a certain access from the building, this can be done after the completion of construction work.

The device of a ring drainage makes sense if it is made no higher than the depth of soil freezing, otherwise the system will not cope with the tasks assigned to it.

Cost of turnkey foundation ring drainage (price per meter)

The amount that ring foundation drainage will cost depends on several factors, so the price is determined individually:

depth of the building foundation;
the perimeter of the building, taking into account the distance from the wall.

The cost will also be affected by the timing and location of the project.

Wall foundation drainage

Wall drainage of the foundation of a house is done in a number of cases:

when installing basement floors at a height of no higher than 50 cm above the groundwater level; when placing buried parts of the house below the calculated groundwater level; when building a house on clay and loamy soils; when the house is located in the area of capillary humidification and preventing the appearance of dampness in the room ;
when constructing a technical basement in clay soils when buried more than 1.3 meters from the surface of the earth.

The distance between the drainage pipe and the wall of the building depends on the width of the foundation and the location of inspection wells. The drain material is selected based on the depth of their installation and taking into account the aggressiveness of groundwater.

The cost of turnkey foundation wall drainage (price per meter)

When ordering foundation drainage, the customer is primarily interested in the cost of the service. PSK "InzhStroyIzolyatsiya" can provide only basic prices for arranging drainage for the foundation of a house, and the price is indicated per linear meter. The total amount is formed taking into account the following factors:

scope of work;
soil type;
drainage material used;
deadlines.

Types of foundation drainage depending on the design

The main purpose of arranging drainage for the foundation of a private house is to protect the structure from moisture entering the basement. Proper installation of the system will prevent flooding of the basement, keeping the foundation dry.

Foundation drainage work is possible both during the construction of a house and in an existing building. The type of system will depend on the type of foundation itself and other factors:

location of the site - hill or lowland;
soil type;
depth of groundwater;
type of house foundation;
relief features;
frequency of precipitation.

And if in one case a simple storm sewer will be enough, then in another it is necessary to install a full-fledged drainage device for the foundation and surrounding soil.

With basement or ground floor

In most cases, the basement of the house is planned to be used as a functional area - boiler rooms, saunas, gyms, even living rooms are located there. That is why they need to be protected as much as possible from groundwater flooding.

For basements and basements, the complex of foundation drainage works includes wall drainage and then high-quality waterproofing of the structure. These measures must be carried out together, since individually they do not solve the problem.

With strip foundation

If the building is erected on a strip foundation, then work on drainage of the foundation will be aimed at preventing the following problems - mobility of the foundation during soil heaving and moisture penetration into the concrete structure.

In this case, a ring drainage is performed, which will drain water from the building and relieve lateral soil pressure.

Grillage or slab on stilts or just a slab

In this case, draining the foundation of the house is an optional procedure. It is advisable to do this in the case when the house is located on clay soil and the owner simply wants to be on the safe side. The only thing you need to remember is that if the slab is mounted on piles, they must be located below the freezing point of the soil in order to prevent the building from moving.

How drainage work is performed

Turnkey foundation drainage includes a set of works to protect the building from contact with groundwater. It is made in the form of a closed system of pipes located at a certain angle below the level of the base of the very foundation of the house. The pipes are connected to each other by special wells to drain water.

If you need high-quality foundation drainage, it is recommended to use wear-resistant two-layer corrugated pipes with a diameter of up to 110 mm for effective water drainage; the price of the work practically does not depend on the selected material.

The complexity of drainage arrangement directly depends on the type of soil, the terrain on which the building stands and the depth of groundwater.

Before laying pipes, it is necessary to carry out a set of measures in stages.

Excavation of the foundation. The outer part of the foundation is thoroughly cleaned of soil, the old waterproofing layer is removed and the foundation is left to dry.
Treating the outer part of the foundation with a primer based on bitumen and kerosene.
After drying, treat the base with moisture-resistant bitumen mastic. It is recommended to fix a special painting mesh into the finished layer of mastic.
After complete drying, another layer of mastic is applied.

Then the next stage of work is when the foundation is drained on a turn-key basis and the necessary materials are prepared (the price directly depends on their quality). The process of setting up the system is as follows.

The building is surrounded by a trench along its entire perimeter at a distance of 1.5 meters from the foundation. All work is carried out taking into account the highest point. The width of the trench should be at least 35 centimeters greater than the width of the pipes.
To install rotary wells at the outer corners, special extensions are made.
A sand layer 25 centimeters thick is poured onto the bottom and thoroughly compacted.
The next stage is laying geotextiles so that the edges protrude beyond the edges of the trench and backfilling with coarse gravel with a layer of up to 20 cm.
Next is the installation of drainage pipes, maintaining a slight slope relative to the lowest point of the system. Bends for rotary wells are fixed at turns.
Installation of a well for pumping water. This is done at a depth of up to 60 centimeters, the bottom of the pit is necessarily covered with geotextiles, and only then a plastic tank with perforated walls is installed.
All pipes are brought to the collection tank at an angle, then covered with crushed stone. The ends of the geotextile are connected and secured with special clamps.

It is very important that after laying the pipes, the drainage is carefully covered with a sand cushion and a layer of turf. Each stage is very important, because a properly designed system will be able to maintain optimal humidity in the area and reliably protect the house from flooding.

What will you get by collaborating with us?

In order to make the water protection system as effective as possible, it is necessary to order professional turnkey foundation drainage, which includes a series of studies, project preparation, and then the implementation of all work to protect the building from moisture. This task can only be done by professionals who not only have the necessary engineering education, but also have sufficient experience. This is the only way to guarantee 100% results.

The PSK InzhStroyIzolyatsiya company has been engaged in drainage arrangement and waterproofing of foundations and other elements of buildings in Moscow and the region for more than ten years. Our team includes only experienced specialists who will carry out work to protect the building from water in the shortest possible time and with high quality. At the same time, you will always be offered a range of work - from studying the structure and soil, drawing up a project to commissioning the facility.

Order turnkey foundation drainage

Have you not yet decided who to entrust the process of creating turnkey foundation drainage? In this case, call us, find out our terms of cooperation - a specialist will come to analyze the object completely free of charge, and make your choice.

It’s easy to submit a request - by phone or by filling out the feedback form.

To begin with, as mentioned earlier, you need to dig out the foundation. In this case, it is necessary to clean the foundation slabs from soil and old waterproofing.
Give the foundation time to dry.

Selection of drainage materials

Particular attention should be paid to materials.

Pipes

Pipes for drainage should be chosen from ceramics, asbestos cement or plastic.

In addition, other types of pipes have a number of significant disadvantages, such as: susceptibility to blockages, short service life (shorter than plastic ones) and the need to drill holes for water supply yourself.

Plastic ones, on the contrary, will last a long time, thanks to the stiffening ribs they can withstand changes in pressure, they are extremely easy to transport and install - they weigh little and bend well.

The inner walls of such pipes are smooth, which increases their self-cleaning ability. Well, and of course, optimal price-quality ratio.

For laying a drainage system, perforated pipes with stiffening ribs are best suited, which will ensure uniform distribution of the load on the pipe. Such pipes are laid to a depth of 5-6 meters, which allows drainage of the foundation of any house.

The diameter of the pipes is selected based on the degree of soil moisture: high groundwater level - 10 centimeter pipes, no - 16.5 centimeters.

Wells

In addition to pipes for foundation drainage, we will also need wells. We need two types: inspection wells and collector wells.

Inspection wells are used to monitor and clean the system from blockages. When there are blockages, a pump goes down into the well and cleans the pipes. Inspection wells are placed at the intersection of pipes at every 2nd turn and every 50 meters on straight pipes. Typically, such wells have a diameter of 60 centimeters.

Collector well represents the final reservoir of the system - the collected moisture enters it. The tightness of the structure eliminates the possibility of leaks and release of water masses. And water from such wells can be used both for watering a plot of land and redirected to an open reservoir.

In addition, our drainage system will also need:, plugs, adapters and elbows. We connect it all using sealing gaskets.

Drainage system calculation

When we have stocked up with all the necessary materials, we can begin to calculate the drainage system of our site. We will need to calculate the depth of pipes and wells and optimal slopes.
Typically, foundation drainage is arranged 0.3-0.5 m below the supporting structure. Pipes should be installed at such a slope that water from them quickly reaches the collector - usually 20 mm for each linear meter.

It is necessary to find the highest and lowest points of the site. In the top (usually the highest corner of the building) we will place a place for accumulating water, and in the other we will place a well for receiving. This way we will create a natural slope, which will save us from the need to buy additional pumps.

What tools do we need?

2 shovels - a shovel and a bayonet, a pick, and a wheelbarrow for removing earth and bringing in crushed stone.

Main works

So let's get started.

First, let's dig trenches for laying our system, while stepping back 1 meter to the side from the foundation. Let's estimate the width of the trench - it should be 20 cm greater than the diameter of the pipe.

When laying pipes, do not forget that the drainage should pass half a meter below the supporting structure.

We compact the trench with a 10 cm cushion of sand. We check the slope, it should remain the same.

We place wide strips of geotextile fabric on the sand so that its ends protrude beyond the boundaries of the trench. Next, we fill in large crushed stone around the foundation - it conducts water well.

Only after all this do we lay the pipes, making sure that they slope toward the lowest point of the system. We connect the pipes using fittings, wrap them with electrical tape just in case and fill them with 10 cm of crushed stone. Then we sew the ends of the geotextile together with threads.

We install the collector at a distance of at least 5 m from the house. It should be located between the levels of the pipe and groundwater. About a meter lower from the pipes. We also cover the pit for the collector with geotextile fabric and only after that we install the well itself. To prevent the well from bevelling in the bottom of the container, you need to drill several holes and secure it firmly. After that, we fill it with gravel and then with earth.

By the way, the trenches should be filled in so that a small mound is formed, because if this is not done, the soil will sag and will have to be filled again.

Unfortunately, it is not always possible to stay within the proposed scheme. In exceptional cases, it is necessary, for example, to purchase additional equipment.

The work of making this type of drainage is quite labor-intensive, because it is necessary to select a large amount of soil and then fill it with crushed stone and sand.

To properly make drainage around the house, you should start making it with markings. To do this, the perimeter is measured and a rope or construction lace is stretched along its edges. After that you can start to soil sampling. Since the insulated slab foundation is a shallowly buried structure, the depth of soil sampling should not exceed 0.5 meters. As a rule, only the fertile layer of soil is removed. Further, to the bottom of the pit geotextiles are laid and wraps around its edges. After this, backfilling and compaction begin. sand cushion. Sand must be compacted using a mechanical vibrator. After a layer of sand, the pit is filled in, leveled and compacted. crushed stone.

Simultaneously with the laying of crushed stone, along the perimeter of the pit is laid drainage pipe in compliance with the required slope. Inspection wells necessary for servicing the system are installed at the corners of the future foundation. The slope of the drainage pipe must be at least two degrees.

The result should be that the drainage pipe is inside the crushed stone layer. If necessary, additional pipes can be laid in several more places, this will enhance the protection of the foundation from moisture.

A receiving well is installed at the outlet of the drainage system pipes. At this point, the work with the drainage system is completed and you can begin further work on the construction of the foundation.

Main mistakes when making drainage

In order to properly drain the foundation, you need to know the main mistakes made when installing it.

The most common mistake when building a drainage system is combining it with gutters coming from the roof of the building. This cannot be done for the simple reason that in the autumn, with a large amount of precipitation, the drainage system may not be able to cope with the removal of large amounts of water and begin to work in reverse mode.

This will certainly affect the soil moisture and it will turn out that all work on drainage and drainage of the site will be in vain.

The second common problem is failure to comply with the required drainage slope. As a result, the system constantly becomes clogged and cannot function normally.

Third is use of drainage pipes without additional filter winding, which also affects the timing of system clogging.

Conclusion

Self-manufacturing of a drainage system is beneficial only in the case of deep ring drainage, manufactured along the outer perimeter of a ready-made drainage system, since work on its implementation does not require the use of special equipment.
In the case of reservoir drainage, all work is much more complicated and requires the specialist to have certain skills, as well as the presence of special tools, such as a level and a vibrating machine.

Useful video

How to install a groundwater drainage system and a roof drainage system:

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