OBO Bettermann MSX-S1 Fire Protection Mortar for Combination Firestops, 20 kg Bag

Standard mortars often fail when sealing complex cable and pipe penetrations that demand certified fire resistance. The OBO Bettermann MSX-S1 Fire Protection Mortar is engineered specifically for combination firestops (Kombischott), delivering reliable fire integrity up to EI 120 / R 120. This mineral-based, non-shrinking mortar comes in a 20 kg bag and ensures your firestop systems remain airtight and durable under extreme conditions.

Who is it for

Fire protection engineers, contractors, and facility managers rely on this mortar to create compliant firestops in walls and floors where multiple services—cables, conduits, and pipes—pass through. It is ideal for both new installations and retrofitting existing penetrations, helping buildings meet stringent fire safety regulations.

Main features

• Certified fire resistance up to EI 120 / R 120 (system-dependent)
• Mineral-based, non-shrinking formula for a durable, airtight seal
• Excellent adhesion to concrete, masonry, and metal surfaces
• Simple mixing with water—approx. 5.5–6.0 L per 20 kg bag
• Workable for approximately 60 minutes at 20°C, allowing ample application time
• Hardens to a walkable/loadable state within 24 hours

Specifications

• Product Type: Fire Protection Mortar
• Application: Combination Firestops (Kombischott)
• Material Basis: Mineral-based
• Colour: Grey
• Net Content: 20 kg
• Mixing Ratio: Approx. 5.5–6.0 L water per 20 kg bag
• Pot Life: Approx. 60 minutes (at 20°C)
• Initial Hardening: Approx. 24 hours (walkable/loadable)
• Full Curing Time: Approx. 28 days
• Density (Fresh Mortar): Approx. 1.8 kg/dm³
• Density (Hardened Mortar): Approx. 1.5 kg/dm³
• Compressive Strength (28 days): > 10 N/mm²
• Thermal Conductivity: Approx. 0.5 W/(m·K)
• Application Temperature: +5°C to +30°C
• Storage Conditions: Dry, cool, frost-free
• Shelf Life: 12 months (in original, unopened packaging)
• Approvals/Certifications: ETA-11/0206, abZ (General Building Inspectorate Approval)

Tips

For best results, ensure surfaces are clean and free of dust before application. Use within the pot life and mix thoroughly to achieve a homogeneous consistency. Protect freshly applied mortar from frost and direct sunlight during curing.