Prompt Natural Cement is a fast-setting, highly breathable, binder extracted and processed from a single raw limestone source in the French Alps. Unlike Portland cement, Prompt is completely natural, unblended, and free from additives, making it ideal for conservation work, rapid-setting applications, and moisture-sensitive environments.
Renowned for its early strength, excellent adhesion, and durability in aggressive or damp conditions, Prompt Natural Cement is widely used in heritage masonry repairs, water-affected areas, and lime-compatible mortars. It can be used on its own or blended with lime to adjust setting times and flexibility.
Key Benefits
✅ Extremely Fast Setting – Sets within 1 to 5 minutes, adjustable with additives or blending with lime.
✅ Natural Hydraulic Binder – 100% natural, sourced from a specific geological deposit without chemical modification.
✅ High Early Strength – Ideal for urgent repairs, patching, or where early resistance is critical.
✅ Breathable & Vapour Open – Maintains moisture movement in masonry, avoiding trapped damp.
✅ Salt & Water Resistant – Performs well in damp, saline, or submerged environments.
✅ Non-Toxic & Eco-Friendly – Low embodied energy, no additives, and suitable for green building and historic restoration.
Applications
🔹 Rapid Masonry Repairs – Ideal for emergency stabilisation or patching of stone, brick, or render.
🔹 Conservation & Heritage Projects – Used where traditional materials and breathable construction are required.
🔹 Waterproofing & Tanking – Performs well in cellars, basements, fountains, and below-grade applications.
🔹 Rendering & Pointing – Used in specialist mixes where a fast set or salt resistance is needed.
🔹 Fixing Metalwork or Anchors in Masonry – Fast-set properties make it ideal for quick structural fixes.
🔹 Moulding & Cast Stone – For fine detail work requiring quick demoulding.
Technical Features
- Setting Time: 1 to 5 minutes (can be modified with retarders or blending)
- Compressive Strength: Rapid early strength – up to 20 MPa in 24 hours
- Colour: Warm ochre/light tan (may vary slightly by batch)
- Packaging: Typically 25 kg bags
- Shelf Life: 6 months (must be stored dry and sealed)
- Compatibility: Lime putty, NHL, aggregates for mortars, renders, and grouts
Why Choose Prompt Natural Cement?
Prompt Natural Cement offers a unique combination of fast setting, durability, and breathability unmatched by synthetic binders. Whether you're working on listed buildings, stonework repair, tanking in damp environments, or eco-conscious projects, Prompt is the preferred binder for specialist craftsmen, conservation professionals, and natural builders across Europe.
