BS EN 1366 fire and smoke ductwork guidance

Everything you need to know about EN 1366 ductwork

Independent UK guidance to BS EN 1366-1, -8 and -9, covering fire-resisting and smoke extract ductwork, classifications, supports, penetrations and evidence.

Start with EN1366 Request a Project Review
EN1366 Five checks before specifying fire or smoke ductwork
  • Choose BS EN 1366-1, -8 or -9.
  • Check size and orientation evidence.
  • Confirm construction and pressure limits.
  • Verify supports and penetrations.
  • Check the protection system evidence.

Core topics

A practical route through BS EN 1366-1, -8 and -9

Compare the main fire-resisting and smoke extract ductwork routes, then check the project-specific evidence.

Fire-resisting ventilation duct passing through a fire-rated wall on paired trapeze supports 01

BS EN 1366-1

Fire resisting ventilation ductwork and the evidence normally reviewed for construction, supports and fire protection.

 Multi-compartment smoke extraction duct passing through fire-rated compartment walls on paired supports 02

BS EN 1366-8

Multi-compartment smoke extract ductwork, pressure and coordination with BS EN 12101-3 smoke fans.

 Single-compartment smoke extraction duct extracting smoke within one room on paired trapeze supports 03

BS EN 1366-9

Single-compartment smoke extract ductwork, size limits and coordination with the selected smoke extract fan.

No overclaiming

Compliance is a system issue, not just a ductwork label.

A ductwork project should be checked against the correct standard part, tested system, construction details, installation method, support arrangement, penetration treatment and certification evidence.

Checklist approach

What project teams should confirm

1. Intended use

BS EN 1366-1 fire-resisting ventilation, BS EN 1366-9 single-compartment smoke extract or BS EN 1366-8 multi-compartment smoke extract.

2. Tested system

Check that the proposed construction sits within the relevant test evidence and field of application.

3. Duct construction

Material, gauge, seams, joints, pressure class, access doors and section lengths should align with evidence.

4. Installation details

Supports, penetrations, insulation thickness, overlaps and fixing method can be as important as the duct itself.

PROJECT SUPPORT

Need practical ductwork support?

Send DuctFix the route, duct sizes, required fire and smoke performance, smoke fan duty and available evidence for an initial project discussion.

Start a Project Review