Rust-Oleum Mathys Dacfill Sloped Roof Waterproofing Grey

Mathys Dacfill is a water-based liquid membrane that forms a lasting, elastic, rubber-like coat with no joints or seams on sloping roofs.

Key features

• 100% watertight, high build coating
• Resistant to UV radiation, acid rain, heat, frost and pollution
• Suits many roof types with a slope of at least 5%: bitumen, cementitious, asphalt and plastics
• Abrasion resistant; hardly flammable and self-extinguishing
• Brush, long-nap roller or airless spray; cleans up with water

Where to use it

Waterproofing of roofs and chimney slabs with a minimum 5% slope. Dacfill can be reinforced with Dacfill fleece, which is needed on roofs with less than 5% slope, where water may stand, or where substrate movement is expected. The system is not designed for immersion. Do not apply on tar, soft PVC, or bituminous materials less than a year old.

Technical details

• Consumption per coat 0.6–1.5 kg/m² depending on substrate; steep roofs without fleece 1.3–2.5 kg/m²; low-slope roofs with fleece 2.5–3 kg/m²
• Touch dry 2 hours; handle 6 hours; recoat 24 hours; fully cured 1 week (20°C)
• Matt finish; density 1.5 g/cm³; VOC 5 g/l
• Dilute with water if necessary for brush or roller; airless nozzle 18–23 at 220 bar
• Apply in drying weather above 5°C, humidity below 80%

Preparation

The roof must be clean and dry, free from flakes, gravel, dust and dirt. Fill joints with Elastofill and bridge active cracks with Dacfill bridging fleece. Prime porous concrete, hard PVC and polyester with Primer 44HS; very smooth concrete with Noxyde diluted 25% with water; iron and steel with undiluted Noxyde; asphalt/bituminous surfaces with Parafix. Roofing more than a year old can be coated directly.

Download the official Dacfill technical data sheet (PDF). Read the safety data sheet and the pack label before use.