Waterproofing terminology.

A waterproofing method that seals active water leaks in concrete by forcing polyurethane resin into cracks, joints, and voids under high pressure. The resin reacts with water to form a flexible, watertight seal — without excavation.

Waterproofing applied to the interior face of a wall or slab — the side opposite the water source. Used when external access is not possible, such as basements, lift pits, and retaining walls where excavation is impractical.

Waterproofing applied to the exterior face of a wall or slab — the side directly exposed to water. The preferred method where external access is available, as it stops water before it enters the structure.

A polyurethane injection resin that reacts with water to expand and form a flexible seal. Used for active leaks where water is present at the injection point. The seal remains flexible and accommodates minor movement.

A polyurethane injection resin that reacts with a catalyst rather than water to form a rigid seal. Used for structural crack repair where movement is not expected and a harder seal is preferred.

A mechanical fitting drilled and set into concrete at intervals along a crack or joint, through which resin is injected under high pressure. Packers are removed after injection and the drill holes are sealed.

The pressure exerted by water against a structure — increases with depth and water table height. The force that drives water through cracks, joints, and porous concrete in basements, lift pits, and retaining walls.

A concrete slab — typically above ground level — that supports a building or serves as a terrace, deck, or plant area. Podium slabs are a common source of waterproofing failures in strata and commercial buildings.

The lowest point of an elevator shaft, typically below ground level. Lift pits are vulnerable to water ingress through the slab and walls, and are often treated with negative-side waterproofing or injection.

A continuous layer — liquid-applied, sheet, or cementitious — that prevents water from passing through a substrate. Membrane selection depends on the substrate, exposure, traffic, and expected movement.

Australian Standard 3740 — Waterproofing of domestic wet areas. Sets out the requirements for waterproofing bathrooms, showers, laundries, and other wet areas in residential buildings, including substrate preparation, membrane coverage, and detailing at junctions.

Australian Standard 4654 — Waterproofing membranes for external above-ground use. Covers membranes for balconies, terraces, podium decks, and other external applications, including substrate preparation, fall, and detailing at drains and penetrations.

The diagnosis and repair of failed or degraded waterproofing in an existing building. Distinct from new construction waterproofing — the work begins with identifying the failure mode and specifying a repair that addresses the cause, not just the symptom.

The process of preparing a concrete or masonry surface before waterproofing — cleaning, crack chasing, joint routing, removing laitance and contaminants, and ensuring the surface is sound and dry enough to accept a membrane or resin bond.

The targeted injection of polyurethane or epoxy resin into a specific crack in concrete to seal it against water ingress or to restore structural continuity. Distinct from surface-applied waterproofing, which addresses the face of the substrate.

The non-destructive process of locating the source of water ingress — using thermal imaging, moisture mapping, dye testing, and flood testing — before any repair is specified. Identifies the failure point so the repair targets the cause, not the symptom.