DELTA

Drainage systems

Components getting in touch with the ground, such as exterior basement walls and similar structure layers integrated into the ground must be sealed in compliance with the standard DIN 18533.

However, simple dimpled sheets cannot be installed on seals according to the standard DIN 18533. The majority of the drainage sheets are used here, which, depending on the type of waterproofing, are additionally equipped with an integrated sliding, protective and load distribution layer. The basic distinction is made between sheet-like seals in accordance with the standard DIN 18533-2 and liquid-applied seals in accordance with the standard DIN 18533-3.

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The type of seal is crucial

On cold, self-adhesive bitumen sheeting, drainage sheets can be used for example to be laid directly, as the HDPE carrier film on the top of the bitumen sheet takes on the function of a protective and sliding layer.

On the other hand, liquid applied seals such as for example polymer-modified bitumen thick coatings are pressure sensitive. In this context, drainage sheets with sliding, protective and load distribution layers must be used since they prevent damage to the waterproofing and the associated consequential damage. These membranes usually consist of three layers: a geotextile used as a filter layer, a dimpled sheet used as a seepage layer and a solid sliding film placed on the smooth rear side of the dimpled sheet.

The filter fleece prevents the fine components of the soil from being slurred into the nub structure and clogging the drainage layer. This way, the seepage layer will remain free of sludge and will drain the water away safely in the long term.

This is the reason why the use of a drainage membrane is a particularly efficient measure for the protection of the building from moisture.