When cables, pipes, conduits, and other services pass through a fire-rated wall or floor, the opening can become a weak point in the fire protection system. If the penetration is not properly sealed, flames, smoke, and hot gases can spread from one fire compartment to another.
A Fire Barrier Composite Sheet is one solution designed to protect large and irregular openings where conventional firestop materials may be difficult to install.
This guide explains what a fire barrier composite sheet is, how it works, where it is used, and what to consider when selecting a firestop composite sheet for industrial and commercial projects.
What Is a Fire Barrier Composite Sheet?
A Fire Barrier Composite Sheet is a pre-formed, multi-layer firestop material designed to seal penetrations and openings in fire-rated walls, floors, and other fire-resistive assemblies.
Unlike conventional firestop sealants, a composite sheet provides a physical barrier over an opening. Many systems combine a metal backing layer, intumescent material, reinforcing mesh, and a protective facing layer.
When exposed to high temperatures, the intumescent material expands and forms a protective char. This expanded layer helps close gaps around penetrations and restrict the passage of flame, smoke, and hot gases.
Fire barrier composite sheets are particularly useful for:
- Cable tray penetrations
- Cable and conduit penetrations
- Pipe penetrations
- Large openings
- Blank openings
- Multiple-service penetrations
- Fire-rated walls and floors
- Intermittent fire barriers in cable tray systems
How Does a Fire Barrier Composite Sheet Work?
The key technology behind many composite firestop sheets is intumescent fire protection.
An intumescent material reacts when exposed to elevated temperatures. Instead of simply melting or burning away, the material expands and forms a protective layer.
The basic process is:
Heat → Intumescent activation → Expansion → Protective formation → Sealing of the opening
The expanded material helps fill voids around penetrations and creates a barrier against fire and smoke.
For example, DAKEN DFB Fire Barrier Composite Sheet has a nominal thickness of 7.8 mm and is designed to expand significantly when exposed to high temperatures. The expanded material helps seal the penetration and maintain the fire barrier between compartments.
What Is a Fire Barrier Composite Sheet Made Of?
A typical fire barrier composite sheet may contain several functional layers.
1. Metal Backing
A galvanized steel layer provides mechanical strength and dimensional stability.
The metal layer also helps the sheet maintain its shape during installation and service.
2. Intumescent Material
The intumescent layer is the primary fire-reactive component.
When exposed to high temperatures, it expands and forms a protective char that helps close openings and reduce fire and smoke transmission.
3. Reinforcing Wire Mesh
A wire mesh layer can provide additional mechanical reinforcement and help maintain the integrity of the composite structure during installation and fire exposure.
4. Protective Aluminum Foil
An aluminum foil facing can protect the internal layers during handling and installation while providing a durable surface.
The exact material composition, thickness, fire rating, and tested configuration depend on the specific manufacturer’s product and firestop system.
Why Use a Fire Barrier Composite Sheet?
A composite sheet can provide several advantages for large or complicated firestop applications.
Easy to Cut and Form
Composite firestop sheets can generally be cut and shaped to suit different opening configurations.
This is particularly useful when an opening contains multiple cables, cable trays, pipes, or conduits.
Suitable for Large Openings
Large penetrations can be difficult to seal using only conventional sealants or putties.
A fire barrier composite sheet can cover a larger area and provide a continuous physical barrier.
Lightweight Construction
Compared with some traditional firestop systems, composite sheets can provide a relatively lightweight solution for large openings.
Suitable for New and Retrofit Projects
Composite sheets can be used in both new construction and retrofit firestopping applications, provided that the installation complies with the applicable tested system.
Re-Enterable Applications
Some composite sheet systems can be removed and reinstalled when additional cables or services need to be installed.
This can be particularly useful in data centers, electrical rooms, industrial facilities, and other areas where services may be modified over time.
Fire Barrier Composite Sheet for Cable Tray Penetrations
Cable trays are one of the most common applications for fire barrier composite sheets.
A cable tray can contain a large number of cables and may pass continuously through fire-rated walls or floors. The penetration must be properly protected so that the opening does not become a pathway for fire and smoke.
A composite firestop sheet can be formed around the cable tray and associated services to create a fire-resistant barrier.
Some systems are also designed as intermittent fire barriers within horizontal or vertical cable tray runs. 3M’s CS-195+ documentation, for example, specifically identifies cable trays and conduit as applications and describes its use as an intermittent fire-break in cable tray runs.
Typical applications include:
- Electrical rooms
- MCC rooms
- Substations
- Data centers
- Power plants
- Oil and gas facilities
- Offshore platforms
- Industrial processing facilities
Fire Barrier Composite Sheet for Large Openings
Large openings are often more difficult to firestop than small penetrations.
A single opening may contain:
- Multiple cables
- Cable trays
- Conduits
- Metal pipes
- Insulated pipes
- HVAC services
- Mixed penetrations
In these situations, a composite sheet can provide a practical method of covering the opening while allowing the sheet to be cut and formed around the penetrating services.
The final fire rating, opening size, penetration type, annular space, fasteners, sealants, and other installation details must always comply with the applicable tested and listed system.
What Fire Rating Does a Fire Barrier Composite Sheet Provide?
Fire rating is one of the most important factors when selecting a fire barrier composite sheet.
Firestop systems may be tested according to standards such as:
- ASTM E814
- ANSI/UL 1479
- CAN/ULC-S115
- Other applicable national or international firestop standards
ASTM E814 / UL 1479 is widely used for evaluating through-penetration firestop systems. The test results are based on specific system configurations rather than simply the material itself.
For example, 3M states that CS-195+ has been tested for firestop applications up to 4 hours under ASTM E814 / UL 1479.
DAKEN DFB Fire Barrier Composite Sheet has been independently tested as a UL 1479 firestop system and provides up to 3 hours of fire resistance for specified applications and configurations.
Important:
A fire rating should not be interpreted as a universal rating for every possible installation.
The actual fire resistance depends on the complete tested assembly, including:
- Wall or floor construction
- Opening size
- Penetration type
- Cable tray configuration
- Pipe size
- Annular space
- Sealant
- Fasteners
- Sheet configuration
- Installation method
Always refer to the manufacturer’s tested system and installation instructions.
How to Choose a Fire Barrier Composite Sheet
Before selecting a fire barrier composite sheet, engineers and contractors should evaluate several factors.
1. Required Fire Rating
Determine whether the project requires 1-hour, 2-hour, 3-hour, or another fire resistance rating.
2. Type of Penetration
Identify whether the opening contains:
- Cables
- Cable trays
- Conduits
- Metal pipes
- Plastic pipes
- HVAC services
- Mixed penetrations
3. Opening Size
The size and geometry of the opening can significantly affect the required firestop configuration.
4. Tested System
Do not select a composite sheet based only on its material properties.
Check whether the proposed configuration has been tested for the intended application.
5. Installation Requirements
Consider how the material will be:
- Cut
- Formed
- Secured
- Sealed
- Joined at seams
- Repaired or modified
6. Maintenance Requirements
For facilities where cables or services may be added in the future, consider whether the firestop system can be accessed and reinstalled without compromising its fire performance.
DAKEN Fire Barrier Composite Sheet
DAKEN DFB Fire Barrier Composite Sheet is a lightweight, multi-layer intumescent firestop sheet designed for large opening and penetration firestopping applications.
The DFB composite structure incorporates a galvanized steel backing, high-expansion intumescent material, reinforcing wire mesh, and aluminum foil facing.
With a nominal thickness of 7.8 mm, the material is designed to expand significantly under fire conditions and form a protective barrier.
DAKEN DFB has been tested according to UL 1479 for specified firestop configurations, with fire resistance of up to 3 hours. Typical applications include cable tray penetrations, mixed-service penetrations, large openings, fire-rated walls and floors, MCC rooms, substations, data centers, oil and gas facilities, and offshore applications.
For detailed product information, see the [DAKEN Fire Barrier Composite Sheet DFB-CS195 product page].
Is DAKEN DFB Similar to 3M CS-195+?
DAKEN DFB and 3M CS-195+ are both fire barrier composite sheet systems based on a multi-layer intumescent construction.
3M describes CS-195+ as a four-component intumescent system consisting of steel, intumescent material, wire mesh, and aluminum foil. It is designed for applications including cable trays, conduit, pipes, large openings, and fire-rated walls and floors.
DAKEN DFB uses a similar general composite-sheet concept, combining steel, intumescent material, reinforcing mesh, and aluminum foil. However, project engineers should evaluate each product based on its own test reports, certifications, tested configurations, installation requirements, and applicable project specifications.
Therefore, rather than assuming that one product is automatically an equivalent of another, it is better to compare the tested firestop system and application requirements.
Fire Barrier Composite Sheet Installation
Although installation methods vary by tested system, a typical composite sheet installation may involve:
- Inspecting the opening and identifying all penetrations.
- Measuring the opening and required sheet dimensions.
- Cutting the composite sheet to the required shape.
- Forming the sheet around the penetrating services.
- Installing the sheet using the specified fasteners.
- Sealing joints, seams, and interfaces with the compatible firestop material.
- Inspecting the completed firestop assembly.
- Confirming that the installation matches the applicable tested system.
For safety and compliance, installation should always follow the manufacturer’s current installation instructions and the applicable tested system. 3M’s installation documentation similarly emphasizes that field conditions such as opening size, pipe size, insulation, and annular space need to comply with the applicable system specifications.
Frequently Asked Questions
Is a Fire Barrier Composite Sheet suitable for large openings?
Yes. One of the main advantages of composite sheets is their ability to cover and adapt to large or irregular openings. The exact allowable opening size and configuration must be confirmed against the manufacturer’s tested system.
What is the difference between a firestop sheet and firestop sealant?
A firestop sheet provides a physical barrier over an opening, while a firestop sealant is generally used to seal joints, gaps, and interfaces. In some tested systems, the two materials are used together.
What standard is used to test firestop systems?
ASTM E814 / ANSI/UL 1479 is one of the major standards used to evaluate through-penetration firestop systems. Other standards may apply depending on the project location and regulatory requirements.
Conclusion
A Fire Barrier Composite Sheet provides a practical approach to protecting large and complicated penetrations in fire-rated walls and floors.
Its combination of a structural backing, intumescent material, reinforcement, and protective facing makes it particularly suitable for applications involving cable trays, conduits, pipes, large openings, and multiple services.
When selecting a fire barrier composite sheet, the most important considerations are not simply material thickness or expansion rate. The complete tested firestop system, required fire rating, penetration configuration, installation method, and project requirements should all be evaluated.
For industrial facilities, oil and gas projects, offshore platforms, power plants, substations, MCC rooms, and data centers, DAKEN DFB provides a lightweight composite firestop solution designed for large opening and cable penetration applications.
Looking for a Fire Barrier Composite Sheet for your project? Contact DAKEN for product data, test reports, installation information, and technical support.