Product Overview
Saint-Astier® NHL 3.5 – The Versatile Lime for Durable Restoration and New Build Projects
Moderately Hydraulic Lime | 3.5 MPa Strength | 100% Natural
Saint-Astier® NHL 3.5 is a pure, moderately hydraulic lime designed for masonry, plastering, and rendering where a balance of strength, flexibility, and breathability is required. Quarried and produced in France, it is ideal for both historic restoration and eco-conscious new builds needing greater durability than NHL 2.
Key Benefits
• Balanced Strength & Flexibility: Offers moderate compressive strength while retaining elasticity for long-lasting, resilient finishes.
• Breathable: Allows moisture vapor to escape, reducing internal wall damp and helping buildings “breathe.”
• Durable in Exterior Conditions: Withstands frost and weather exposure, making it suitable for demanding external applications.
• Natural Composition: Contains no additives or cement—just 100% natural hydraulic lime for healthy buildings.
• Excellent Bonding: Achieves superior adhesion on a variety of substrates, including stone, brick, and block.
Recommended Applications
• Exterior Rendering: Provides a tough yet breathable weather-resistant finish.
• Masonry Work: Ideal for laying stone, brick, or block in traditional or new construction.
• Repointing: Suitable for medium-hard masonry requiring a balance of strength and flexibility.
• Scratch Coats and Base Plasters: Performs well as a first coat in multi-coat lime systems.
• Eco-Builds: Compatible with natural insulation systems like woodchip, hempcrete, and clay mixes.
Application Guidelines
• Mixing: Blend with sharp, clean sand (with a good range of particle sizes) and potable water. Avoid excessive water.
• Surface Preparation: Ensure the substrate is clean and slightly damp before application to aid adhesion and reduce rapid drying.
• Application Conditions: Apply between 8°C and 30°C. Protect freshly applied lime from frost, direct sun, and wind.
• Curing: Keep the applied material moist for at least 5–7 days to ensure proper carbonation and strength development.
• Reworking Time: Mortar remains workable for up to 24 hours; remixing does not reduce performance.
Packaging and Storage
• Available Sizes: 25 kg bags.
• Shelf Life: Up to 12 months when kept sealed and stored in a dry location.
Notable Projects
• Church Restoration: Used in the repair of historic stone churches where both durability and breathability were essential.
• Eco-Renovation: Chosen for rendering in passive house retrofits, due to its natural performance and thermal compatibility.
• Seaside Properties: Successfully applied in coastal environments where exposure to salt and wind demand resilience.