Flat Roof Waterproofing with Bituminous Membranes

Waterproofing with Bituminous Membranes is the most commonly used waterproofing solution, as bituminous membranes offer excellent adhesion to all typical substrates such as concrete, lightweight concrete, perlite concrete, and similar surfaces. They are available in various grades to meet every construction requirement.
In single-layer applications where the membrane remains exposed to weather conditions, the use of high-density elastomeric bituminous membranes is recommended, ensuring increased durability and extended service life.

Application Procedure:

• Thorough cleaning of the substrate, removal of loose or deteriorated areas, and repair of surface defects.
• If proper slopes are not present, they are formed using lightweight concrete to prevent water ponding.
• Application of a bituminous primer (Arexol Lac) to the surface.
• Torch-applied installation of the bituminous membranes. For single-layer systems, membranes weighing 5 kg or 6 kg are recommended.
• Reinforcement of joints and critical points using acrylic, bituminous, or bitumen-polyurethane sealant (Hyperdesmo PB 1K).
• Optionally, mechanical fixing of the membrane edges with a metal termination bar, where feasible.

Note: If conversion of the waterproofing system into a walkable surface is required, a reinforced cement screed with a minimum thickness of 3 cm must be applied over the membranes, followed by tile installation using a flexible tile adhesive (Kerastile G2).