The drainage of an individual site is done by collecting the groundwater and then evacuating it. This prevents them from reaching and damaging the foundations of the dwelling. Discover in this article, the principles of implementation of the drainage system.
Individual plot where to install the drainage system?
The location of the drainage depends on the conformation of the residential building, its surroundings, but also the nature of his basement.
- Generally, the drain is installed so that it runs along the foundations of the house, on the "foundation footing" (infrastructure work) or nearby. In no case should you install the drain lower. This location avoids any risk of scouring (digging).
- For this reason, in the case where the drain could only be placed next to the footing, it should be installed on a bed of lean concrete, itself placed according to the slope of flow.
- In case of brickwork near the foundations, such as a terrace, the drain must be spaced about 2m from the walls. A solution that protects the foundations of the house in case of ground movements.
In any case, only the prime contractor is able to define the ideal location of the drainage.
Technique of drainage of an individual ground
Preferred for individual plots are terracotta, porous concrete or rigid PVC drains with a minimum diameter of 100mm.
The drain must havea flow gradient of 3 to 10mm / m. This flow is always from the highest point of the ground to the lowest, and the water thus harvested is then redirected to:
- a sewer
- or a sump
- or an underground spreading
The drain itself is subjected to a step "Coating":
1. coating of pebbles
2. layer of gravel
4. Cover of sand and soil of permeable fill.
In the case of sandy soils, the drain should be protected by a "geotextile" (non-woven rot-proof fabric) that will allow water to pass while avoiding the obstruction of the drain.
To note: the flow slope must be adjusted along the route and ground if necessary by adding or removing gravel.