Chemsol Chemolastic PU

Chemsol Chemolastic PU is a single-component PU-modified bitumen-based elastomeric waterproofing system. It forms a highly elastic, UV-resistant membrane suitable for both exposed and concealed applications. The product is easy to apply using a roller or brush and provides long-term durability under extreme environmental conditions.

Applications

• New roofs
• Podium waterproofing
• Retaining walls, wet areas, bridges
• UV-resistant—suitable for exposed surfaces
• Refurbishment of old membrane systems including torch-on membranes

Features

• Single-component, UV-resistant formula with long-term aging stability.
• Cured membrane remains stable at extreme temperatures (-25°C to 120°C).
• Resistant to chlorides and sulphates commonly found in soil.
• Easy to apply with brush, roller, or squeegee.
• Highly elastic—up to 900% elongation.
• Excellent adhesion to various substrates, suitable for a wide range of applications.

Method of Application

1. Surface Preparation

• Ensure the surface is clean, dry, and in sound condition.
• Remove all dirt, grease, and loose particles. Wash the surface thoroughly with clean water.
• Remove any previous coatings completely before application.

2. New Surfaces

• Ensure newly constructed surfaces are fully cured before coating.

3. Cracks and Joint Treatment

• Open surface cracks (0–5 mm) using a 3 mm angle grinder and clean thoroughly.
• Fill small cracks with an acrylic crack filler or PU sealant.
• Repair cracks larger than 5 mm using polymer-modified mortar with Chemsol Chemfast SBR (cement:sand = 1:3, polymer = 10% by cement weight). Cure properly before coating.

4. Pre-Application Testing

• Conduct a ponding test to identify porous surfaces.
• Grout porous surfaces to seal them before coating application.
• Perform a second ponding test to confirm surface readiness.

5. Priming

• Apply a priming coat using Chemsol Chemolastic PU diluted 200% with water (40 L water to 20 L product).
• Maintain a coverage of 8–10 Sqm/L depending on surface finish.

6. Application

• Mix the bucket contents thoroughly before application.
• Reinforce drain outlets and joints using fiberglass mesh embedded in the coating.
• Apply the first coat (20% dilution) at a coverage of 0.33 L/Sqm/Coat and allow to air dry for at least 6 hours.
• Apply the second coat (20% dilution) at 90° to the first coat with the same coverage and allow 6 hours of drying.
• For higher performance, apply fiberglass mesh reinforcement between coats.

7. Ponding

• Allow the system to air cure for 7–8 days before performing the pond test.
• Limit ponding water height to not more than 5 cm.

Precautions and Limitations

• Do not dilute Chemsol Chemolastic PU beyond the recommended dosage.
• Keep the container tightly closed when not in use.
• Treat corners, joints, and repair areas with two extra coats.
• Not suitable for water-retaining structures (e.g., tanks, pools).
• Avoid excessive film thickness to prevent microbubbles; it does not affect integrity but should be minimized.
• Apply late afternoon or evening to minimize outgassing effects.
• Apply one coat of acrylic coating on top if exposed to open sky to reduce dust attraction.

Technical Information

Theoretical Coverage

Maintain material consumption of approximately 0.33 L/m² per coat for two coats, achieving a total thickness of 0.5–0.6 mm.

Pack Size

1 L and 20 L

Storage

Chemsol Chemolastic PU shall be stored in a cool, dry place protected from direct sunlight.

Shelf Life

24 months from the date of manufacturing if unopened and stored properly.

Health and Safety

• Wash skin with soap and water after contact.
• In case of eye contact, rinse immediately with water and consult a physician if irritation persists.
• If ingested, consult a doctor immediately.