Drainage device around the house: do-it-yourself design and improvement of the drainage system
The drainage system is designed to protect underground structures from the effects of groundwater. We need it in areas with difficult hydrogeological conditions, among which we have the majority of land plots. The drainage device around the house will extend the life of the foundation, will save from eternal repairs. It is cheaper to prevent the destruction of the foundations of the building than to infinitely restore, do you agree?
How to organize the drainage around a private house, our visitors will learn in detail from the presented article. A detailed description of the types and principles of the drying system will help determine the best option for the device. Using the reliable information offered by us, you will be able to build an impeccably operating network for the removal of groundwater.
Those who wish to build a closed drainage on their own, we will find a detailed description of the technology and a step-by-step account of the sequence of works. The text part is perfectly complemented by photo-confirmation and video instruction.
The reasons for the organization of the drainage system
A special system of drainage pipes or channels is arranged in such a way that as much moisture as possible gets inside and moves a safe distance from the house or other buildings. The problem of the impact of moisture on the foundation is usually characteristic of clay soils: sandy loam, loam, clay.
In an area with a predominance of clay rocks in the section, water is slowly absorbed or does not leave at all. Due to the stagnation of the water, the base of the house is destroyed The existing waterproofing protection of the foundation may be insufficient, it may be slightly glued seams, areas unworked with mastic.
As a result, there is mold, fungus on the concrete monolith, corrosion on the reinforcement, which later often becomes the cause of the foundation destruction.
On sandy, well-permeable soils, moisture leaves faster, so this kind of problem occurs less frequently. But still the owner of the house should not relax and rely on “maybe” in this matter. Excessive wetting of the structure may be due not only to the characteristics of the soil, but also to other features of the site. For example, a high level of groundwater that prevents moisture from leaking from the overlying layers down.
If the bottom of the wall after the rain for a long time is covered with wet spots, this indicates that you need to think about the need for drainage facilities. Wet walls in the basement, the presence of mold or fungus shows that the problem of drainage in the area should have been taken yesterday.
Even a very good waterproofing of the foundation eventually becomes useless. This is another reason to take care of good drainage near the house. The smaller the impact of groundwater on the structural parts of the structure, the less often large-scale work will be required to restore the waterproofing layer applied to the foundation.
If the collection and disposal of groundwater and flood water were not foreseen during the construction phase, after construction you can take care of the drainage around the house and its device with your own hands.
Typical drainage types
There are several basic drainage systems with which you can collect and remove unnecessary moisture from the house and from the site. With proper design and installation, each of them demonstrates a fairly high efficiency, but here the time, effort and money costs depend on the complexity of the design, which can be:
Open drainage systemsare ditches with a depth of about 50-70 cm and a width of the order of half a meter. Such ditches are dug around the house is not a problem, but the landscape will noticeably suffer from this. Yes, and jump all the time through the grooves surrounding the house, not too convenient.
Open drainage is usually covered with neat decorative gratings. They protect the structure from coarse debris and blockages caused by it. And such grooves with grids look more aesthetically pleasing.
Backfill drainage systemsthey are approximately the same ditches, only they are not covered with protective gratings, but they are filled with moisture permeable material, for example, coarse gravel, broken brick or rubble. It is not so difficult to arrange drainage of this type, and the costs will be quite moderate.
Before starting work, you need to mark up and carefully cut the sod at the site of excavation. Ditches fall asleep to the top, so that there is not enough space. The turfs stored for this purpose are placed on top of the backfill in order to minimize damage to the landscape of the site. It is recommended to lay a layer of geo-text at the bottom of the ditch in order to extend the life of the structure.
This version of the drainage system has some drawbacks: it is harder to clean than an open system.Of course, debris in such a drainage is unlikely, but the problem of silting the contents of ditches remains. In the event that the efficiency of moisture removal decreases markedly, you may have to remove the turf again, completely replace the filler, and then return the system to its previous state.
Closed drainagethe most difficult to install, but at the same time it is reliable and has a long service life. A layer of gravel or similar materials is laid in the drainage ditches, pipes with a perforated surface are placed on top. Usually they use plastic structures, they are cheaper, they weigh less and it is easier to perform perforations on their surface than on metal analogues.
Closed drainage systems are most conveniently mounted along a curb of walkways surrounding a house. Here, the entire system will be safely hidden and will not affect the appearance of the site. There is also such a thing as wall drainage.
He is satisfied in the process of building a house in cases where the planned construction of the basement or basement. Drainage pipes are laid directly in the foundation pit near the walls, and then all this is filled up with filtering material and soil.
Another important element of the system is storm drainage. These are open trays, which are designed to collect and transport water collected from the roof and blind area of the house during rain. Storm drainage is also open and closed, it is usually installed under the drain pipes attached to the gutters and funnels.
Design of a groundwater drainage system
Of course, the drainage system consists not only of pipes and trays. To monitor the state of the system, manholes are needed, and a drainage well should be arranged in which this excess moisture will be drained. For this reason, the ditches in which pipes are laid are given a slight slope towards this well.
It makes sense to consider the procedure for installing a closed drainage system, since it is the most difficult to perform. Open and backfill option can be arranged on the basis of the same principles. Pipes of the closed system are laid around the perimeter of the building at a distance of 0.7 - 1.0 m from it. By analogy, grooves are formed for the open and backfill drainage scheme.
At each corner where the trench is rotated, inspection wells should be installed. In advance, it is necessary to determine the location of the collector well, to which the discharge of the diverted water will be carried out.
If it is intended to collect water outside the site, then a drainage well is arranged. From it lay another pipe, which usually goes to the roadside ditch. You can divert to the local water body, if there is one in the immediate vicinity of the house.
The depth of the trench under the closed drainage depends on the size of the foundation. Pipes should be laid 50 cm deeper than base plates. In this case, the slope of communications should be 0.7-1%. You should not lay pipes with a large slope, as this can cause blockages. Small bias is also not recommended as it will negatively affect the process of moisture removal.
The trench width should be greater than the diameter of the drainage pipe by 20 cm: 10 cm of clearance on each side. The location of the drainage system should be schematically reflected on paper, denoting all its elements. This will allow to calculate the length of communications, as well as the number of additional elements necessary for the proper installation of the system.
Features of the closed type building
Having figured out how to properly drain around the house, and having made a project, you should prepare for further work. It should stock up on materials, as well as the necessary tools. During the work you may need:
- twine for marking and marking the position of communications;
- building level and plumb to control pipe slope;
- bayonet and shovel;
- tool for tamping soil;
- a bucket and / or a wheelbarrow for transporting waste land;
- measuring tape;
- hacksaw, etc.
You will also need a certain number of drainage pipes. These are special designs with perforation, usually they are made of plastic. Instead of them, you can use plastic pipes for external sewage, having previously drilled holes on their surface with an ordinary drill. It will also require geotextiles, sand, crushed stone or other similar material, manholes by the number of turns, etc.
Geotextiles are necessary in order to protect the filler surrounding the drainage pipe from the penetration of fine clay particles and siltation. Save on this material is not worth it. It should be enough to completely cover the walls and bottom of the excavated trench, as well as cover the buried pipe with a solid overlap.
First, it is recommended to perform markings on the ground, and then proceed to earthworks. Usually they start digging from the highest point of the system, gradually deepening the trench. Calculate the slope is not difficult if you focus on a standard of 1%. If the trench length is 20 m, then the height difference between its initial and end point should be 20 cm. The necessary measurements are performed using a conventional tape measure.
After the trench is ready, its bottom must be carefully tamped. Then a layer of sand is poured at the bottom of 10 cm, which is also carefully rammed. After that, it is recommended to cover the entire trench with a layer of geotextile so that both the bottom and the walls of the structure are covered, and the edges of the material come out to the surface and lie freely on the ground.
Now, on the bottom, hidden by geotextiles, you need to pour a layer of gravel about 20 cm. Any filtering material will be acceptable: crushed stone, expanded clay, fragments of brick, etc. The main thing is that its fraction should be larger than the size of the holes in the drainage pipes, otherwise blockages can not be avoided.
After laying the gravel should be leveled and be sure to check the slope of communications, it should correspond to the previously performed calculations and measurements.
If everything is in order, drainage pipes are laid on the gravel, connected to the observation and drainage wells. Then the system is filled with another layer of gravel (crushed stone, expanded clay, etc.) The height of this layer should also be 20 cm. The edges of the geotextiles, which remain free, are wrapped over the layer of backfill.
The overlap of the layers of non-woven material should be about 30 cm. Sometimes it is recommended to fix the position of the geotextile material using a twine or plastic clips.
Now you can fill the rest of the trench with sand (need a layer of 10 cm) and soil. The sand must be compacted again, especially in the space to the sides of the drainage pipe. Top cut previously sod or mount tracks. You can also come up with your own option for decorating the place of laying drainage pipes. There must be access to the manholes, as well as to the point of discharge of the abstracted moisture.
Inspection wells are plastic vertical tanks, closed lids.They are used to periodically check the status of the system. The drainage well is a wider tank, it can be round or square in configuration. Most often for its arrangement use an old plastic barrel.
You can also use concrete rings of suitable diameter or make walls of monolithic concrete. In the latter case, be sure to perform the reinforcement structure. The top of the drainage well should be closed with a strong lid.
Purpose of the blind area and its device
Supplemental drainage of the blind area around the house will also help protect the walls and foundation from unnecessary moisture. So called a layer of waterproof material, which is placed along the walls with a slope outward. Falling on the blind area, immediately drain away from the house, so the contact of the walls and the foundation with moisture will be minimal.
To perform a blind area, you can use materials such as:
- a rock;
- paving slabs;
- PVP membrane.
Installation of a blind area of clay and stone, as well as of paving slabs can be quite time-consuming, but this finish looks just fine. Asphalting and concreting will be much cheaper, but it looks very modest, even utilitarian. PVP-membranes are mounted in the ground column, from above you can arrange any convenient covering: turf, tile, lawn, etc.
Conclusions and useful video on the topic
The procedure for doing drainage at home with your own hands is clearly presented in this video:
Interesting drainage tips can be found here:
Execution option blind area around the house:
Obviously, to protect the house from moisture, you need to take a number of measures, and the drainage system should be effectively combined with a blind area, rainfall, etc. In the future, all efforts will pay off, because the foundation of the house, its walls and the ground floor for a long time will not need to be repaired.