Basement waterproofing | Margaretenau Regensburg

Basement rooms at new-build level

The waterproofing work must be carried out precisely and exactly as specified by specialised tradesmen. This is the only way to achieve a perfectly sealed basement wall that allows high-quality utilisation of the basement rooms to the level of a new building.

Sealing on uneven surfaces

The Margaretenau building co-operative in Regensburg, which is over 100 years old, is continuously renovating its building stock, some of which is almost 100 years old.

Now another property in the Margaretenau residential neighbourhood has been raised to modern living standards - including, of course, upgrading the building and basement waterproofing. To create the vertical waterproofing, the entire basement area had to be exposed down to the foundation base. The masonry consists of tamped concrete and has a very uneven surface. As waterproofing compounds must be applied in a uniform thickness in order to avoid stress cracks and thus leaks, a special levelling plaster had to be applied in advance.

maxit san Stop levelling plaster

Once the masonry had dried, the coarse-grained concrete was cleaned and any loose particles removed. This was followed by the full-surface application of a special bonding bridge, which creates the adhesive bond on damp masonry for the subsequent levelling plaster. This bonding bridge was fully covered with maxit san primer, a coarse-grained, adhesion-modified primer made of highly sulphate-compatible special cement.

In the next step, the aforementioned levelling plaster was applied. This special mortar has a low shrinkage tendency and is equipped with a water barrier. maxit san Stop was specially designed as a levelling plaster for basement masonry in existing buildings and was applied here in thicknesses of 1 - 4 cm.

After a waiting time of around 1 day per mm of plaster thickness - after the release of approx. 50 % of the water contained - the primer coat of maxit san bitumen primer was applied. Once this had dried, the actual bituminous waterproofing of maxit san Superdicht 2K was applied. The determination of water impact class W 2.1-E "Moderate impact of pressing water" in accordance with DIN 18533 was the decisive factor for the waterproofing to be applied in two layers with a total wet layer thickness of 5 mm. In addition, maxit reinforcement mesh MW was embedded.

In the plinth area, the bituminous compound was replaced in accordance with DIN 18533 by a plasterable sealing slurry made of maxit AD-1K external sealant, which overlaps the basement waterproofing by 10 cm. The final layers were the perimeter insulation and the standardised, three-layer dimpled membrane.

Building cooperative Margaretenau eG

Michael Leitner GmbH, Pettendorf

LUXGREEN Climadesign, Regensburg

Time period:
2021 – 2022


  • maxit san Vorspritz
  • maxit san Bitumengrundierung (bitumen primer)
  • maxit AD-1K-Außendicht
  • maxit Armierungsgewebe MW (reinforcing mesh)
  • maxit san Stop
  • maxit san Superdicht 2K

Project location