1. Ensure the concrete roof slab is clean, dry, and free from dust, debris, oil, and standing water. Repair any hairline cracks using instant cement or sealant until the surface is level and smooth.
2. Apply bitumen primer evenly over the entire surface. Allow it to dry to a tack-free condition (approximately 2–4 hours, depending on weather conditions). The primer acts as a bonding layer between the concrete substrate and the membrane.
3. Position the Casali membrane over the application area. Heat the underside of the membrane using a gas torch, then gradually roll it forward while continuously applying heat. Ensure the flame is evenly distributed to achieve proper adhesion.
4. Install each membrane sheet with an overlap of 10–15 cm. Carefully heat the overlapping areas and press firmly to ensure a secure and watertight bond.
5. Press the installed membrane using foot pressure or a roller to ensure full contact with the substrate and to eliminate trapped air or bubbles.
6. After installation is complete and the membrane has cooled, perform a ponding test for 24–48 hours to ensure the system is watertight and free from leakage.