ALCHIMICA΄s cementitious under tile waterproofing system for balconies and teracces, seals and acts as a barrier to prevent any water ingression that may lead to corrosion. It offers long-term protection thanks to its excellent elasticity, flexibility and hydrophobic features, while offering ease of application on horizontal and vertical substrates alike. The system assures the water tightness of the concrete substrate and eliminates problems that usually appear, over time, by the detaching or cracking of tiles in low temperatures.