Waterproofing of concrete basement walls

In most countries, different standards and/or guidelines regulate in-situ concrete basements and precast concrete structures.

For this concern, the German Committee for Reinforced Concrete (DAfStb) has drawn up a guideline ("Water Impermeable Concrete Structures"). For a performing waterproofing of in-situ concrete or prefabricated concrete elements, the waterproofing between the concrete elements as well as between concrete slab and concrete elements is most important. Two-component waterproofing coatings have proven being performing in this case. The execution of a full-surface waterproofing with e.g. polymer-modified bitumen thick coatings (PMBC) on concrete basements is particularly economical, since the partly high density of steel reinforcement of concrete walls can be reduced by the waterproofing system. In this case, the waterproofing function is fully taken over by the bitumen thick coatings.

Waterproofing

Simple & safe to the goal

1. Remove all adhesion-impairing particles and substances, for ex. cement laitance from the forepart of concrete slab with a diamond rotative disc.
2. Fill the groove area between the forepart of concrete slab and the prefabricated concrete wall elements with the watertight mortar weber.tec 933, using the preformed trowel weber.sys Hohlkehlenschlitten along the angle. weber.tec 933 can also be used for closing working and butt joints of prefabricated concrete elements.
3. Use the bitumen primer weber.tec 901, diluted with water in a ratio of 1 : 10 parts by volume on the joint areas of the prepared prefabricated concrete elements.
4. Apply a first layer of weber.tec Superflex 10 (2-comp. lightweight bitumen waterproofing thick coating) on the area between prefabricated elements and concrete slab. The layer must cover at least 15 cm of the forepart of the concrete slab.
5. Lay the woven glass fiber mesh weber.sys 981 over the first layer of weber.tec Superflex 10.
6. Apply a second layer of weber.tec Superflex 10 over weber.sys 981.
7. Apply a first layer of weber.tec Superflex 10 over the vertical butt joints between the concrete elements.
8. Lay a strip of the fabric insert weber.sys 981 over the first layer of weber.tec Superflex 10 over the pre-said joints.
9. Apply a second layer weber.tec Superflex 10 over weber.sys 981.
10. On main surfaces use the bitumen primer weber.tec 901, diluted with water in a ratio of 1 : 10 parts by volume on the concrete surface.
11. Apply a thin scratch layer and afterwards a first layer weber.tec Superflex 10with insertion of the woven glass fiber mesh weber.sys 981.
12. Apply a second layer weber.tec Superflex 10 over the mesh.
13. Lay the protective and drainage foil weber.sys 983 over the thoroughly dried waterproofing layers and fix it with the metal rail weber.sys 983 A at the upper side of the bitumen layer.