Waterproofing & Floor Levelling Sydney: Complete Process

Waterproofing and floor levelling are two trades that must work together. A waterproofing membrane on an uneven slab will fail. A levelled floor without proper falls will pond. For Sydney builders, getting the sequence right is essential for compliance and long-term performance.

The Correct Sequence

The correct sequence for wet areas is: structural slab → levelling with falls → waterproofing membrane → floor covering.

Some builders try to apply waterproofing directly to the structural slab to save time. This is a mistake. The structural slab is not flat enough for a membrane to perform properly. Hollows create thin spots in the membrane. Humps create stress points. The result is a membrane that fails within months.

Creating Falls with Pumped Screed

PowerPump's screed system can create falls to drainage points as part of the levelling process. The falls are controlled by laser level and screeded to the correct gradient. The result is a flat, sloped surface that meets AS 3740 requirements for wet area drainage.

For commercial bathrooms, kitchens, and plant rooms, the ability to create falls in a single pour is a significant programme advantage. Traditional hand-packing of falls is slow, imprecise, and labour-intensive.

Waterproofing Membrane Compatibility

Not all levelling compounds are compatible with all waterproofing membranes. Hychem's levelling systems are tested and approved for use with Hychem waterproofing membranes. This compatibility is essential for warranty coverage. Using an unapproved levelling compound can void the waterproofing warranty.

Compliance and Documentation

AS 3740 requires wet areas to have falls to drainage points, a waterproofing membrane, and documentation of the installation. PowerPump's printed docket for the levelling pour provides part of this documentation. The waterproofing applicator provides the rest. Together, the documentation package satisfies certifier and insurance requirements.