Description:

Koster 21 is a 2 component, solvent-free, liquid applied, elastic, crack bridging waterproofing material with excellent adhesion to dry and moist substrates.
Koster 21 is liquid applied and seamless, which greatly eases application to complicated architectural details. 21 seals against synthetic oils and aliphatic hydrocarbons with high boiling points (up to 2 bar).
Koster 21 does not contain volatile organic compounds (VOC content = 0), is free of polyurethanes, isocyanates, and bitumen.

Features:

• Elastic and crack-bridging.
• For indoor and outdoor application: resistant to UV-radiation, salt, hydrolysis, and freeze / thaw effects.
• Good adhesion to slightly moist mineral substrates.
• Good adhesion to a wide variety of materials.
• Easy to apply.
• Resistant to pressurized water.
• Hydrophobic (water repelling effect).

Uses:

• Waterproofing balconies and terraces, also before installing ceramic tiles.
• Waterproofing Basements.
• Waterproofing Roofs (with occasional foot traffic).
• Waterproofing Tanks and basins.
• Carbonisation inhibiting.
• Protection against aliphatic oils.
• Waterproofing old bituminous surfaces (renovation).
• Waterproofing concrete slabs.