Ductwork
Fire-Resisting Ductwork
Led by IFE-qualified supervisors, our experienced installation teams specialise in the installation of Flamebar fire-resisting ductwork systems. Rigorously tested to BS EN 1366 Parts 1, 8 and 9, these systems provide up to 120 minutes of fire resistance, supporting the protection of occupants, escape routes and critical firefighting access.
We install systems for a range of applications, including fire-resisting ventilation ductwork, multi-compartment smoke control and single-compartment smoke control.
Flamebar BS EN 1366-1
Fire Resisting Ductwork.
Independently tested and certified to BS EN 1366-1, the Flamebar system provides up to 120 minutes of fire resistance for both integrity (E) and insulation (I). Performance is classified in accordance with BS EN 13501-3.
The system is manufactured from galvanised mild steel as standard, with stainless-steel options available on request. Ductwork is produced to a third-party certified fabrication standard, ensuring consistent manufacturing quality and compliance.
External surfaces are coated with either:
- Flamebar BW11 — for integrity-only (E) applications
- Flamebar BW18 — where both integrity and insulation (EI) performance is required
Depending on the specification and required performance, the coating is applied at approximately 1–2 mm thickness.
Ductwork is supplied in modular sections and assembled on site using Flamebar fire-rated gaskets and sealants tested as part of the complete system configuration. This ensures fire performance is maintained across joints and interfaces, helping preserve the integrity of fire compartments in accordance with the project’s fire safety design.
The completed Flamebar BS EN 1366-1 system supports passive fire protection requirements, helping protect escape routes and maintain safe access for firefighting operations during a fire.
BS EN 1366-8
Fire Resisting Multi Compartment Smoke Control Ductwork
Designed for multi-compartment smoke control applications, the Flamebar BS EN 1366-8 system has been rigorously tested to BS EN 1366-8, achieving up to 120 minutes of fire resistance for both integrity (E) and insulation (I), while maintaining 90% effective free area.
The system is classified in accordance with BS EN 13501-4.
Manufactured from precision-formed galvanised sheet steel, the ductwork is produced to a third-party certified quality assurance standard. External surfaces are treated with a proprietary water-based compound:
- Flamebar BW11 — for non-insulated configurations
- Flamebar BW18 — for applications requiring thermal insulation
The system has demonstrated performance under standardised cellulosic fire exposure conditions for internal applications.
Supplied in modular sections for efficient site assembly, the ductwork is jointed using tested Flamebar fire-resisting gaskets and/or sealants. This helps maintain continuous fire compartmentation and system performance across fire-rated zones.
The BS EN 1366-8 system supports compliant smoke control strategies, helping maintain protected means of escape and firefighting access in accordance with relevant building regulations and project-specific smoke control requirements.
BS EN 1366-9
Fire-Resisting Single-Compartment Smoke Control Ductwork
The Flamebar FPL-09 system has been independently tested to BS EN 1366-9, demonstrating fire integrity performance of up to 120 minutes.
Engineered for single-compartment smoke control applications, the system is designed to remain operational under flashover conditions of 600°C or above, while retaining a minimum 90% free cross-sectional area. This helps maintain effective smoke extraction under high-temperature fire conditions.
The system is classified in accordance with BS EN 13501-4 for the fire resistance performance of smoke control ducts.
Manufactured from galvanised steel sheet, all components are produced under third-party accredited quality assurance procedures to ensure dimensional accuracy, material consistency and reliable system performance.
The ductwork is supplied in prefabricated sections for site assembly. Joints are completed using tested and certified Flamebar fire-resistant gaskets and sealants, helping maintain compartmentation integrity throughout the installed system.
The Flamebar BS EN 1366-9 system provides a robust solution for single-compartment smoke control, supporting safe means of egress and protected access for firefighting operations in accordance with relevant fire safety requirements and smoke control design criteria.
Why choose our service?
Whether maintaining an existing system or preparing for a new installation, FSL’s surveying service gives you confidence that your fire resisting ductwork meets the highest standards of safety and compliance.
Customer
testimonials
Hear what our clients say about our fire safety services
Mace
FSL came to the project on short notice but left a lasting impression on the client and main contractor alike. The works undertaken were carried out quickly, safely and to the highest standard. The site team tidied up at the end of every shift, coordinated their works to allow other project deadlines to be achieved and left catalogue standard finished product to top it off. Off site support with compliance guidance and project management was seamless and all works passed quality inspections and system testing first time, what more could a project ask for!
Would highly recommend.
Phoenix ME
We have been extremely impressed with the expertise and product knowledge demonstrated by Fire Specialists Ltd.
Their fire rated ductwork solutions were delivered with the expected level of attention to Design, compliance, installation, and final sign off in line with all relevant standards and regulations. Their strong commercial awareness and ability to coordinate effectively with the programme meant they maintained programme and on budget.
We would not hesitate to work with FSL again on future projects.
Frequently Asked Questions
Common questions about our fire safety services and installations
Fire-resisting ductwork is designed to maintain its performance when exposed to fire, helping protect building compartments, escape routes and firefighting access. Flamebar systems are tested to relevant parts of BS EN 1366 and can provide up to 120 minutes of fire resistance, depending on the system and application.
Our Flamebar systems are tested to BS EN 1366-1, BS EN 1366-8 and BS EN 1366-9, depending on the intended application. Fire classification is carried out in accordance with the relevant BS EN 13501 classification standard.
Depending on the system specification, Flamebar fire-resisting ductwork can provide up to 120 minutes of fire resistance. The exact performance depends on the system, application and whether integrity and insulation performance are required.
The three standards relate to different ductwork applications:
- BS EN 1366-1 — fire-resisting ventilation ductwork.
- BS EN 1366-8 — multi-compartment smoke control ductwork.
- BS EN 1366-9 — single-compartment smoke control ductwork.
The correct system depends on the building design, compartmentation strategy and smoke control requirements.
E refers to fire integrity — the ability of the ductwork to prevent the passage of fire and hot gases.
EI refers to both integrity (E) and insulation (I). In addition to maintaining integrity, the system limits heat transfer through the ductwork for the specified period.
Flamebar BW11 is used for applications requiring integrity-only (E) fire performance. It is a waterborne fire-resistant coating incorporating selected mineral fillers within a low-permeability elastomeric binder.
Flamebar BW18 is used where both integrity and insulation (EI) performance is required. The coating forms part of the tested Flamebar system configuration.
Flamebar ductwork is generally manufactured from galvanised mild steel or galvanised sheet steel. Stainless steel options are also available for certain applications, subject to specification.
Ductwork is supplied in modular or prefabricated sections and assembled on site. Joints are completed using tested Flamebar fire-rated gaskets and sealants appropriate to the system. Using the specified components helps maintain the tested fire performance across joints and interfaces.
Multi-compartment smoke control ductwork is designed to pass through multiple fire compartments while maintaining its required fire resistance and smoke control performance.
Single-compartment smoke control ductwork is designed for smoke extraction applications where the ductwork remains within a single fire compartment.
Effective free area refers to the unobstructed cross-sectional area available for airflow through the duct. Maintaining a minimum 90% free area helps the smoke control system continue to provide effective airflow under the relevant fire test conditions.
Yes. The ductwork is manufactured to third-party certified or accredited quality assurance procedures, helping ensure consistency in materials, dimensions and manufacturing quality.
Fire-resisting ductwork is a tested system, and its performance depends on the correct specification, manufacture, assembly and installation of its components. Correct installation of duct sections, joints, gaskets, sealants and coatings is essential to maintaining the intended fire performance.
Yes. The appropriate system depends on factors including the building design, ductwork application, fire compartmentation, required fire resistance period and smoke control strategy. Our experienced installation teams can work with project requirements to identify the appropriate Flamebar system and installation approach.
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Experts in Fire Safety. Committed to Your Project.
Every project is different, but our commitment remains the same—delivering expert advice, compliant solutions, and exceptional service from start to finish.
Whether you require fire-resisting ductwork, enclosure systems, commercial kitchen fire protection, or technical support, our knowledgeable team is ready to help.
