Premium bitumen-based waterproof coating
Hydroproof 300
Black
Seamless Protection. Flexible Performance. Reliable Waterproofing.
A premium, single-component, bitumen-based waterproof coating that cures to a
seamless, elastomeric membrane — a tough barrier against water penetration and moisture ingress,
engineered to flex and move with the structure beneath it.
Key benefits
Built to move with the building
Standard membranes crack, blister and let moisture in under extreme heat, intense UV, aggressive ground salts and constant structural movement. Hydroproof 300 is formulated for exactly those conditions.
- Single-component formulation — no mixing, no pot life to manage
- Cures to a seamless, flexible membrane with zero joints or laps
- High resistance to water penetration and moisture ingress
- More than 300% elongation at break, bridging substrate cracks
- Applied by brush, roller or airless spray
- Pitch- and coal-tar-free, non-toxic, low VOC
Where it works
Four applications, one membrane
The same tin covers below-ground concrete, exposed roof decks, under-tile wet areas and bare metal — which keeps the specification simple and the site stock small.
Foundations
Below-ground concrete structures and retaining walls, where ground salts and lateral water migration attack the substrate.
Roofing
Concrete roofs, balconies and terraces that take the full load of UV, heat and thermal movement.
Wet areas
Under-tile waterproofing in bathrooms and kitchens, sealing the substrate before tiling begins.
Metal protection
Corrugated iron sheets and storage tanks, protected against corrosion and standing water.
Preparation
The foundation every coat depends on
Most membrane failures are preparation failures. Work through these four stages before the first coat goes down.
Clean
Remove all dust, oil, grease, grime and loose particles from the substrate.
Pressure wash
Wash the entire surface with a pressure washer to guarantee absolute cleanliness, then allow it to dry.
Inspect
Systematically check the surface for overall structural soundness before committing to the coating.
Repair
Open, clean and fill small cracks with crack sealer. Repair larger damaged or hollow areas with polymer-modified screed.
The three-layer build
Anchor, core, shield
Once the surface is prepared, Hydroproof 300 goes on in three purpose-built layers. Each plays a different role — anchoring to the substrate, building thickness, then sealing everything beneath a shield.
| Layer 1 — the anchor | Self-priming coat. Hydroproof 300 — Black diluted 3:1 with water. |
|---|---|
| Layer 2 — the core | Second coat, applied neat with zero dilution. |
| Layer 3 — the shield | Third coat, applied neat with zero dilution. |
| Drying protocol | Allow 4–6 hours of drying time between each coat. |
One range.
Complete protection.
Waterproofing is not one product, it is a system. Hydroproof 300 Black is the flagship, and every other coat in the range is built to work with it, from preparing the surface to finishing it.
Hydroproof 300 Black
The single-component, liquid-applied waterproof membrane the rest of the range is built around. Start here if you are waterproofing a roof, foundation, wet area or metal surface.
- 300%+ elongation, bridges cracks
- 1 tin no mixing on site
- 3 ways to apply: brush, roller, spray
Backed by a full system for every surface and stage
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Prepare the surface
Hydroproof Primer
Seals and prepares the substrate so the waterproof coat bonds properly.
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Waterproof
Hydroproof 300 White
The white version of the flagship. Single-component, liquid-applied elastomeric membrane.
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Waterproof
Hydroproof PU Black
High-performance, liquid-applied polyurethane waterproofing membrane in black.
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Waterproof
Hydroproof PU White
High-performance, liquid-applied polyurethane waterproofing membrane in white.
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Waterproof
Hydroproof 2K Cement
Two-component cementitious waterproofing for concrete and masonry.
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Protect and finish
Hydroproof Cool Coat
Heat-reflective coating that helps keep roof surfaces cooler.
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Protect and finish
Hydroproof Crystal
Clear, transparent water-repellent protection that keeps the surface looking as it is.
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Protect and finish
Hydroproof Clear Coat Matt
Clear matt finish coat that protects the surface below.
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Protect and finish
Royal Coat Flaxseal
Flexible sealing coat from the Royal Coat range.
Technical data
| Type | Single-component, bitumen-based elastomeric waterproof coating |
|---|---|
| Colour | Black |
| Packaging | 5 kg and 20 kg |
| Elongation at break | Greater than 300% |
| Application | Brush, roller or airless spray |
| Coats | Minimum 2 coats; 3-layer build recommended |
| Recoat interval | 4–6 hours between coats |
| VOC content | Low |
| System | Surface prep → Hydroproof 300 — Black → min. 2 coats → protective finish where required |
More than 300% elongation lets the membrane absorb minor structural movement and bridge cracks caused by expansion and contraction, so it moves with the structure instead of tearing away from it.
Specify Hydroproof 300 on your next project
Send us the substrate, the exposure and the area, and we will return coverage figures, a full specification and the TDS/SDS pack.