Liquid rubber waterproofing and elastomeric roof coating systems for flat and pitched roofs — practical solutions for restoration, remediation, and new-build waterproofing in Auckland.
Cohe supplies liquid rubber and elastomeric waterproofing systems used for roof restoration, concrete waterproofing, and water containment applications. Their product range is built around ease of application and long service life.
Cohe's product line is centred on liquid-applied waterproofing — systems that go on by brush or roller, cure to form a seamless elastomeric membrane, and handle the thermal movement and ponding water that older roof surfaces struggle with.
The liquid rubber approach is particularly well suited to roof restoration work: roofs that still have structural integrity but need a fresh waterproofing layer applied over the existing surface without a full tear-off. AquaProof uses Cohe products where the project calls for a fluid-applied system over an existing substrate.
Product range
The Cohe range covers pitched and flat roof restoration through to liquid rubber waterproofing for concrete surfaces and water containment.
An elastomeric waterproofing coating system designed for sloped and pitched roof surfaces. Applied to existing roof substrates to restore waterproofing performance without replacement. Carries up to a 10-year waterproofing warranty when installed to specification.
A higher-specification elastomeric system for flat roofs and internal gutters. Designed to bridge existing surface cracking, seal penetrations, and restore full waterproofing performance on deteriorated flat roof areas. Carries up to a 20-year warranty when correctly applied.
The primary waterproofing coat in the Cohe liquid rubber system. Applied in 2–3 heavy coats with a minimum 12-hour recoat interval. Coverage is approximately 1 litre per square metre per coat — producing a seamless elastomeric layer across the substrate surface.
The finishing topcoat applied 72 hours after the base waterproofing layer. Seals and protects the liquid rubber below, providing UV stability and a smooth finished surface. Applied in 2–3 coats at approximately 1 litre per 3 square metres per coat.
A reinforcing tape used to bridge joints, seams, skylights, vents, and penetrations within the Cohe liquid rubber system. Embedded into the wet base coat, it provides additional thickness and reinforcement at the points most vulnerable to movement and water entry.
A surface-applied water repellent coating for concrete, masonry, and porous substrates. Used where the goal is to reduce water absorption and capillary action without applying a full waterproofing membrane — retaining walls, concrete walls, and exposed masonry surfaces.
Why liquid rubber
Sheet membranes have lap joints — and lap joints can fail. A liquid rubber system cures as a single continuous layer with no seams, overlaps, or joints. In areas with complex geometry — multiple penetrations, internal corners, junctions — this is a significant advantage.
The C200 and C500 systems are designed to be applied over existing roof surfaces. Where the substrate has retained structural integrity but the waterproofing layer has degraded, a Cohe system can restore performance without a full tear-off — reducing cost and disruption.
Liquid rubber is applied at ambient temperature. No gas torches, no open flame, no hot asphalt. This makes it suitable for projects where hot works permits are difficult to obtain, or where proximity to sensitive areas makes torch-on membrane impractical.
FAQ
The C200 is designed for pitched (sloped) roofs and carries up to a 10-year warranty. The C500 is formulated for flat roofs and internal gutters — higher-specification and carrying up to a 20-year warranty. The right system depends on roof pitch, current surface condition, and warranty requirements.
In many cases, yes — provided the existing surface is structurally sound, clean, and properly prepared. Compatibility depends on the type and condition of the existing coating. We assess this at the site visit and recommend accordingly before committing to a system.
The Cohe liquid rubber system requires a minimum of 2–3 heavy coats of the waterproof sealant as the base, followed by 2–3 coats of the smooth coating topcoat applied 72 hours after the base layer. Total system application typically takes 2–3 days depending on weather and surface area.
Cohe's liquid rubber products are used for water containment applications including water tanks and ponds. Compatibility with potable water storage depends on the specific product specification — contact us for guidance on the appropriate system for water tank waterproofing.
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