External Basement Waterproofing with Bitumen Based Waterproofing Systems

The use of bituminous products belongs to the standard solutions for the positive side waterproofing of basements. The systems are applied in a paste-like form and are therefore seamless. They are easy and safe to use and have crack bridging properties. On clean, solid, stable, gypsum free mineral substrates KÖSTER Polysil TG 500 is applied as a primer. This immobilizes salts present in the substrate and the substrate is solidified. When preparing to waterproof on top of old bituminous coatings KÖSTER Bitumen Primer is used.

Pipe and cable penetrations are sealed with the permanently plastic putty KÖSTER KB-Flex 200 and protected by a layer of KÖSTER KB-Fix 5. Alternatively these areas can be connected with a fillet of the respective thick film sealant or fitted with flanges.

To protect against water creeping behind the lower waterproofing connections KÖSTER NB 1 Grey mixed with KÖSTER NB 1 Flex is applied first. To prevent stresses in the waterproofing, rounded fillets are installed in the wall / floor junctions.

The actual area waterproofing is achieved using KÖSTER Deuxan 2C in two layers applied by trowel. KÖSTER Deuxan Professional can be spray applied. For greater ease of manual application use KÖSTER Bikuthan 1C or 2C. The addition of KÖSTER Glass Fiber Mesh is recommended in all thick film sealants and all applications. This allows for a better control of the coating thickness and safely absorbs movement in the building.

Before backfilling the positive side waterproofing is to be protected from mechanical damages and settling with KÖSTER SD Protection and Drainage Sheet.

Always adhere to the specifications in the respective Technical Guidelines.

1 Primer
KÖSTER Polysil TG 500
2 Waterproofing pipe penetrations
KÖSTER KB-Flex 200
3 Preparing wall/floor junctions
KÖSTER NB 1 Grey
4 Installing fillets
KÖSTER Repair Mortar Plus
5 Waterproofing layer
KÖSTER Deuxan 2C
KÖSTER Deuxan 2C (UK)
6 Reinforcement
KÖSTER Glass Fiber Mesh
7 Protection of the waterproofing layer
KÖSTER SD Protection and Drainage Sheet 3-400