Intumescent coated batts are a specialized type of fire-stopping material used to seal openings and gaps in fire-rated walls, floors, and ceilings. They are typically made from mineral wool (or other fire-resistant insulation) and are coated with an intumescent material. When exposed to high temperatures during a fire, the intumescent coating expands, sealing off penetrations to prevent the spread of fire, smoke, and toxic gases through the opening.
Key Features of Intumescent Coated Batts:
- Core Material:
- The core of the batt is usually made from high-density mineral wool or rockwool, which is naturally fire-resistant. This core provides thermal insulation and acts as a base for the intumescent coating.
- Intumescent Coating:
- The intumescent coating is applied to the surface of the mineral wool batt. Under fire conditions, this coating expands when exposed to heat, creating a dense, fire-resistant barrier that seals off any gaps or spaces.
- Fire-Stopping Properties:
- When installed in wall or floor penetrations, intumescent coated batts prevent the spread of fire by expanding and sealing the penetration, stopping the movement of flames, smoke, and hot gases. This ensures the fire compartmentation integrity is maintained, protecting the adjacent spaces.
- Flexible for Multiple Penetrations:
- These batts can be cut or shaped to fit around various service penetrations, such as pipes, cables, or ducts. Once installed, the expanded intumescent material helps to maintain the fire resistance of the barrier even around complex or irregular penetrations.
- Typical Fire Ratings:
- Intumescent coated batts are designed to provide up to 2 to 4 hours of fire resistance, depending on the product and installation details. They are tested to meet specific fire performance standards, such as BS EN 1366-3 (European standard for fire-stopping in penetrations) or UL (Underwriters Laboratories) fire-resistance standards.
- Acoustic Insulation:
- In addition to fire resistance, the dense mineral wool core also offers acoustic insulation, reducing noise transmission through the sealed penetrations. This makes them ideal for use in commercial buildings where both fire protection and soundproofing are required.
Applications:
Intumescent coated batts are used in a variety of settings to maintain the integrity of fire-rated walls and floors. Typical applications include:
- Service Penetrations:
- Where pipes, cables, or ducts pass through fire-rated barriers. The batts are installed around these penetrations to ensure that fire compartmentation is maintained.
- Large Openings:
- In walls or floors where there are large openings, for example, in mechanical rooms or service shafts, the batts can be installed to close off these areas while allowing services to pass through.
- Cavity Barriers:
- Used as a cavity barrier in external cladding systems or behind facade panels, helping to stop the spread of fire through hidden cavities in building envelopes.
- Curtain Wall Firestopping:
- In high-rise buildings, they can be installed in the gap between the edge of the floor slab and the curtain wall system to prevent vertical fire spread.
Installation Process:
- Measuring and Cutting:
- The batt is cut to fit the size and shape of the penetration or opening. A tight fit is essential to ensure the best fire protection.
- Sealing Gaps:
- Any gaps around the edges of the batt or the service penetrations (pipes, cables) are sealed using compatible intumescent sealants or coatings to create a complete barrier.
- Fastening:
- The batt is typically friction-fitted into the opening, or it may be secured with mechanical fasteners to hold it in place. For certain applications, additional fire-resistant mastic or sealant may be applied to ensure airtightness and fire resistance.
- Verification:
- After installation, the system should be inspected to ensure it meets the fire-stopping standards required by local building codes or fire regulations.
Benefits:
- Fire Resistance: Can provide up to 4 hours of fire protection.
- Versatility: Suitable for multiple types of penetrations and openings.
- Non-Combustible Core: The mineral wool core is inherently fire-resistant.
- Acoustic Insulation: Helps reduce sound transmission.
- Easy to Install: Can be cut and shaped on-site to fit different penetrations.
- Durability: Intumescent coated batts maintain their integrity over time, even in high-humidity environments.
Compliance and Testing:
Intumescent coated batts are tested to meet stringent fire safety standards to ensure they provide effective fire-stopping. They are typically certified by bodies like UL, FM Global, or BS EN, depending on the region. Proper installation is essential to ensure compliance with building regulations, such as NFPA 101 in the US or Approved Document B in the UK.
Summary:
Intumescent coated batts are a highly effective fire-stopping solution used to seal penetrations in fire-rated barriers. By combining a mineral wool core with an intumescent coating, these batts provide excellent fire resistance, preventing the spread of flames and smoke, while also offering acoustic insulation. Their versatility and ease of installation make them an ideal choice for maintaining fire compartmentation in buildings with various service penetrations.