Hydrophobix and Hydrocalce; what you need to know about our water repelling products
Overview
These water-repellent products are designed to protect lime-based and other mineral finishes from water while maintaining vapor permeability. They provide long-lasting durability, enhanced stain resistance, and suitability for interior and exterior applications, including wet environments like showers or on facades. While all three products serve a similar purpose, their specific features vary and this post lays it all out. For more information and tips on using these products read Top Tips from Cait: Hydrophobix & Hydrocalce
1. Product-Specific Guidelines
Hydrophobix Concentrate (Whitson’s Ltd)
- Description: A highly concentrated water-repellent formula designed for lime-based finishes. Offers excellent stain resistance and stain release and superior water and oil resistance. Suitable for treating larger areas.
- Dilution: Mix 1 part concentrate with 8 parts clean tap water by volume.
- Use distilled or deionized water in hard water areas.
- Coverage: 250g/m² or approximately 4m²/liter when diluted, depending on the substrate’s porosity.
- Best For: Larger surfaces or professional users
Hydrophobix Ready to Use (Whitson’s Ltd)
- Description: A pre-diluted, ready-to-use version of Hydrophobix Concentrate for smaller or more convenient applications.
- Dilution: Do not dilute further.
- Coverage: 250g/m² or approximately 4m²/liter.
- Best For: DIY or smaller-scale projects.
Hydrocalce (Stucco Italiano)
- Description: Eco-friendly, water-based waterproofer with deep penetration. Designed for mineral plasters, bricks, and other porous substrates, providing a non-film-forming, invisible finish.
- Versions:
- Concentrate: Dilute 1 part concentrate with 5 parts water by weight.
- Ready to Use: Can be lightly diluted (e.g., 1 part Hydrocalce to 0.5 parts water) for smooth finishes like Marmorino Fine.
- Coverage: 120-240 ml/m² for two coats, depending on substrate porosity.
- Best For: Eco-conscious projects, especially on vertical exterior surfaces.
2. Preparation
Proper preparation ensures maximum product performance and durability.
- Surface Preparation:
- Ensure the substrate is clean, free of dust, oils, and grease.
- Lime plasters must cure for at least 72 hours (3 days) for full carbonation.
- High humidity, poor airflow, or moisture-resistant backing boards may extend drying times.
- Compatibility Test:
- Always test the product on a small, inconspicuous area to ensure compatibility with the substrate.
- Dilution:
- Hydrophobix Concentrate: 1 Part Hydrophobix Concentrate with 8 Parts Clean Tap Water by volume and mix well. In hard water areas we recommend that distilled or deionised water is used.
- Hydrocalce Concentrate: Textured finishes: Mix 1 part product with 5 parts distilled water (by weight).
- Smooth finishes: Mix 1 part product with 10 parts distilled water (by weight).
- Stir pre-diluted products (Hydrophobix Ready to Use ) before application.
3. Application
Follow these steps to achieve optimal results:
Conditions:
- Ambient temperature: Between 8°C and 35°C.
- Avoid applying in direct sunlight or damp conditions.
- Protect surfaces from rain or high humidity during and after application.
Tools:
- Brush, roller, or spray gun.
Procedure:
- Application:
- Apply 3 wet-on-wet coats for comprehensive coverage.
- Work from the bottom up to avoid splashing untreated areas.
- Ensure even distribution, avoiding drips or pooling.
- Drying:
- Protect the treated area from liquids or humidity for:
- 48 hours for Hydrophobix.
- 72 hours for Hydrocalce.
- Protect the treated area from liquids or humidity for:
Coverage Rates:
- Adjust based on substrate porosity:
- Hydrophobix: Approx. 250g/m².
- Hydrocalce: 120-240 ml/m².
4. Drying and Post-Application Care
- Hydrophobix: Water and oil repellency fully develop within 48 hours.
- Hydrocalce: Touch-dry in 2 hours; full depth drying in 72 hours.
- Ensure adequate ventilation during the drying process to promote chemical reactions and durability.
5. Cleaning and Storage
- Clean all tools immediately with water.
- Periodically clean equipment during prolonged use to avoid residue buildup.
- Store products in a cool, dry place away from extreme temperatures and out of reach of children.
- Shelf Life:
- Hydrophobix: 12 months (unopened).
- Hydrocalce: 24 months (unopened).
6. Safety Precautions
- Use in well-ventilated areas.
- Avoid contact with skin and eyes. Wear eye protection. In case of contact:
- Rinse eyes with water and seek medical advice.
- Wash skin with soap and water (no solvents).
- Do not ingest. If swallowed, seek immediate medical attention.
- Dispose of product and packaging responsibly, adhering to local regulations.
7. Performance Insights
- Water Repellency:
- Hydrophobix prevents water absorption for over 6 hours in comparison to untreated and competitor-treated samples.
- Hydrocalce provides an invisible finish while resisting water penetration effectively.
- Stain Resistance:
- Hydrophobix significantly reduces staining from common substances like coffee, red wine, and oil.
- Eco-Friendly Properties:
- Hydrocalce is solvent-free and complies with EU VOC limits.
For additional guidance or troubleshooting, contact:
- Whitson’s Ltd: +44 (0) 1738 442800
Or take a look at our handy TDS and SDS sheets below for more information
Hydrophobix Concentrate – SDS TDS
Hydrophobix Ready to Use – SDS TDS
Hydrocalce – SDS TDS
