Firestop Depot
3M™ Fire Barrier Water Tight Sealant 1000 NS – Gray, 20 fl oz Sausage Pack
3M™ Fire Barrier Water Tight Sealant 1000 NS – Gray, 20 fl oz Sausage Pack
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Protect your fire-rated penetrations with a sealant engineered to perform in demanding environments. 3M™ Fire Barrier Water Tight Sealant 1000 NS is a premium, neutral-cure silicone firestop sealant that helps prevent the spread of fire, smoke, toxic gases, and water infiltration—all in one reliable solution. Designed for commercial construction professionals, it delivers dependable performance where long-term durability and code compliance matter most.
This ready-to-use, non-slump sealant cures upon exposure to atmospheric moisture, creating a flexible, watertight firestop seal with exceptional adhesion and weather resistance. It provides up to 3 hours of fire protection in tested systems while accommodating movement in dynamic and static construction joints. Its re-enterable and repairable design makes future maintenance simple, helping contractors save time without compromising protection.
Ideal for perimeter fire barrier systems, curtain wall joints, penetrations through fire-rated walls and floors, and blank openings, this high-performance sealant also reduces airborne sound transmission and meets UL water leakage requirements for qualifying systems. Whether you're working on commercial, industrial, or institutional projects, 3M™ Fire Barrier Water Tight Sealant 1000 NS delivers the performance professionals trust.
Key Benefits
- Up to 3-hour fire protection in tested firestop systems
- Water-tight performance for qualifying UL-rated applications
- Neutral-cure silicone formula with exceptional weather resistance
- Flexible seal accommodates ±31% joint movement
- Strong adhesion with non-slump consistency for clean installation
- Helps block fire, smoke, toxic gases, and water intrusion
- Reduces airborne sound transmission (STC Rating up to 56)
- Re-enterable, repairable, and paintable with primer
- Compatible with CPVC piping
- Ideal for commercial, industrial, and institutional construction
Recommended Applications
- Dynamic and static construction joints
- Curtain wall and perimeter fire barrier systems
- Fire-rated wall and floor penetrations
- Blank openings
- Mechanical, electrical, and plumbing (MEP) penetrations
- Commercial firestop installations requiring water-tight protection
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We've tried several firestop sealants over the years, but this one stands out for its quality and ease of use. The self-leveling consistency saves time on every installation, and the performance has been outstanding. Great product from 3M and definitely worth keeping in stock.
Excellent product and exactly what we needed for fire-rated floor penetrations. It flows evenly without extra tooling, bonds well to concrete, and gives us confidence knowing it meets the required firestop and water-tight standards. Highly recommended for professional contractors.
We've been using the 3M Fire Barrier Water Tight Sealant 1000 NS on several commercial projects, primarily around floor penetrations. The self-leveling formula makes installation incredibly fast, and the finished seal looks clean every time. It has become our go-to product for horizontal applications."