How Superior Roof Slab Waterproofing Saves You Money: Cost, Details, Advantages, Lifespan, and Warranty Guide

In Brisbane and other regions with strict compliance standards, substrate preparation is one of the most critical steps a Brisbane waterproofer undertakes before applying any membrane or coating

• Clean the roof slab thoroughly to remove dust, oil, grease, and loose particles.
• Repair any concrete slab cracks or honeycombs using non-shrink grout or polymer-modified mortar.
• Ensure the surface is dry and free from standing water before application.

Crack and joint treatment is a vital step in roof slab waterproofing to ensure long-term durability and prevent water ingress. The process begins with identifying and cleaning all cracks and joints to remove dust, loose material, and contaminants.

Proper crack and joint treatment — including the use of concrete slab crack repair epoxy — ensures the membrane’s continuity and flexibility, providing a watertight, durable barrier that complies with AS 4654.2 and meets SuperiorWaterproofing’s quality standards for roof slab protection.

• Apply a compatible primer supplied or recommended by the membrane manufacturer using a roller or brush.
• The primer promotes adhesion between the concrete slab and the waterproofing membrane.
• Ensure full, uniform coverage without puddles.
• Allow the primer to cure for the specified time (typically 1–2 hours for polyurethane systems, or as per manufacturer data sheet) before applying the main membrane.

• Our Brisbane and Gold Coast waterproofer use a  polyurethane-based liquid membrane, approved for Australian external applications (AS 4654.1 compliant).
• We apply two coats using a brush, roller, or spray equipment in perpendicular directions.
• Typical coverage rate: 1.5–2.0 kg/m² per coat, achieving a final dry film thickness between  1.2mm–1.5 mm.
• Reinforce corners, fillets, penetrations, and joints with a glass-fiber mesh or polyester fabric between coats.
• Extend the membrane up parapet walls a minimum of 150 mm above the finished floor level.
• Allow the membrane to cure completely (usually 24–48 hours) before subsequent layers.

• All pipe penetrations, drains, and outlets must be sealed with compatible flexible sealants and properly integrated with the waterproofing membrane.
• Ensure protection during subsequent trades’ work — avoid sharp tools, heavy traffic, or direct mechanical damage on the waterproofed surface.
• After waterproofing on flat roof slab, our licensed waterproofer conducts visual inspection, membrane thickness tests (for liquid membranes), and a flood / water test (e.g. 24-hour ponding test) must be performed before covering.
• All terminations, laps, edges, penetration details, and continuity must be inspected.
• In all waterproofing slab roof, we provide warranties, system certificates, and as-built drawings.