What is rubber waterproof roof coating?
Rubber waterproof roof coating is a single-component, water-based elastomeric membrane made from modified acrylic or styrene-acrylic rubber emulsion. Applied liquid by roller or brush at 1.0–1.5 mm, it cures into a seamless rubber-like film that stretches over 300% of its original length, bridging hairline cracks in concrete and metal roofs while remaining fully waterproof under ponding water. MagicalPaint supplies the coating in 20 kg buckets for contractors and distributors.
When to choose rubber coating instead of bitumen or TPO membrane
| Factor | Rubber liquid coating | Bitumen / torch-on membrane | TPO / PVC sheet |
| Application | Roller or brush, no flame | Torch or hot mop, fire risk | Hot-air welding, specialist crew |
| Seams | None — fully seamless | Overlapped seams, common leak point | Welded seams |
| Crack bridging | > 300% elongation | Limited | Moderate |
| Complex detailing | Paints around pipes and vents easily | Difficult | Requires custom fabrication |
| Recoat / repair | Recoat any time, no stripping | Often full replacement | Patch welding |
| Typical life | 8–12 years | 10–15 years | 20–30 years |
| Cost | Low | Medium | High |
Key performance data
| Property | Typical value | Test method |
| Elongation at break | ≥ 300% | GB/T 16777 |
| Tensile strength | ≥ 1.5 MPa | GB/T 16777 |
| Water impermeability | 0.3 MPa / 30 min, no leak | GB/T 16777 |
| Crack bridging | up to 2 mm | — |
| Solid content | ≥ 65% | GB/T 16777 |
| Coverage | 1.6–2.0 kg/m² at 1.2 mm DFT | — |
| Service temperature | −20 °C to 80 °C | — |
| Solar reflectance (white) | ≥ 0.80 | ASTM C1549 |
| VOC | < 50 g/L, water-based | GB 18582 |
| Pack size | 20 kg pail | — |
Where it is used
- Flat and low-slope concrete roofs
- Metal roof sheets, corrugated iron and colour-steel tiles
- Roof penetrations, vents, skylights and pipe boots
- Gutters, parapets and flashing details
- Balconies, podium decks and planter boxes (under screed)
Application sequence
- Inspect: Find and repair active leaks and structural cracks wider than 2 mm. The coating is a waterproofing layer, not a structural repair.
- Clean: Pressure-wash to remove dust, moss and flaking material. Allow the roof to dry completely — substrate moisture must be below 10%.
- Prime: On porous concrete, apply a diluted first coat (10% water) as primer. On metal, use a rust-inhibitive primer first.
- Reinforce: Embed polyester reinforcement fleece at cracks, joints and upstands while the first coat is wet.
- Top coats: Apply two full coats at right angles, 1.6–2.0 kg/m² total. Allow 4–8 h between coats.
- Cure: Protect from rain for 24 h. Full cure in 7 days.
Common mistakes
- Applying over a damp substrate — trapped moisture blisters the film within weeks.
- One thick coat instead of two thin coats, causing uneven curing and pinholes.
- Skipping reinforcement at the wall-to-roof junction, which is where most leaks start.
- Using white coating without a primer on bitumen, leading to brown bleed-through.
Product Name
Rubberized waterproofing coating for roofs — Highly elastic exposed roof protection experts.
Core Advantages
Excellent Performance
- Extreme elasticity: elongation at break＞800%, adapt to extreme temperature difference from -40℃ to 100℃, seamlessly cover cracks, resist ultraviolet aging, 10 years of durable protection.
- Strong bonding: penetrate the substrate 0.3mm to form a grip, impermeable pressure of 0.3MPa, resistant to freezing and thawing, typhoon and salt spray.
Environmental safety: water-based formula, zero VOC, no solvent odor. - Convenient construction: single-component open barrel ready to use, no need to mix, open barrel ready to paint, support roller/brush/spray, 8 hours table dry, single day construction area of 100 square meters.
- Wide adaptability: Wet substrate can be constructed, yin and yang corners, pipe roots and other complex parts are easy to deal with, the construction temperature range of 5 ° C – 40 ° C.
Economical and efficient
- Low consumption and high coverage: 1.5mm thickness can be reached after 2-3 times of painting (2.0-2.2kg/m2), saving 50% labor cost.
- Maintenance-free design: Exposed coating without additional protective layer, anti-aging and maintenance-free.
Scope of application
- Metal plant, garage roof, tropical rainforest climate zone roof (resistance to high temperature 120 ℃, mold and algae)
- Flat roofs of residential buildings, roofs covered with snow and ice (-20℃ anti-freezing and cracking), basements and bridge joints.
- New and old roofs, tunnels, parking lots, exterior wall repair and leakage, polyurethane / coil crack repair