Drainage in clay soil - is this necessary?


The soil condition may be quite different at different building sites and on different plots. What problems especially a clay soil with regard to the infiltration brings with it, and whether a drainage is necessary there, learn here.

Heavy and cohesive soils

Soils are always after their drainage capability assessed. Loamy and peaty soils are often referred to by experts as "heavy" or "cohesive" soils. In them, water trickles away very slowly.

The lack of infiltration capability of the soil may cause rainwater to build up and drain into the soil too slowly. Around house walls this should be avoided as far as possible in order to avoid moisture damage.

On land, a lack of infiltration capability can lead to large puddles and stagnant water after heavy rainfall. In addition, there is the risk that plants can rot and die in an overly humidified soil.

Drainage in buildings

For soils with very poor infiltration capacity, the installer usually arranges the installation of a drainage system. Decisive for this are the am geological survey proven infiltration rate in the soil and the general soil condition. For this, the groundwater situation must always be assessed.

Drainages are basically used for the derivation of Rainwater and not groundwater, Is the groundwater level above the base of the foundation (always the highest ever measured groundwater level is used) Under no circumstances may drainage be applied!.

Drainage on land

For gardens and land, creating a drainage can make sense to improve poorly drained soil. This is especially advisable with clay soil, if:

  • Frequently stagnant water is observed in the meadow
  • On the property something is planted (here, if necessary, but also raised beds
  • Fruit trees should stand or stand on the property

How to properly drain the land should be discussed with a specialist (GaLa-Bau). You will also find some useful hints in our special article.

Tips & Tricks

Drainage of buildings is often superfluous in many cases. In any case, the DIN demands a waterproofing in new buildings, which has been able to cope with all load cases in relation to water, and the building blocks are practically always waterproofed today. For old buildings is - if the cellar is damp, first of all the seal repaired. That is fundamental. There is a drainage not a suitable means of cellar dryingbecause the cause is usually elsewhere.


Video Board: Geo Fabric and French Drains