Fire Protection Of Ductwork

In many situations, passive fire protection of metal ductwork can be the most suitable way to ensure fire safety of ventilation, kitchen extract and smoke extraction ducts across your building. ISOVER offers solutions with ULTIMATE mineral wool that provide fire resistance to metal ductwork while delivering thermal and acoustic benefits.

Fire Protection Of Ductwork

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The fire resistance of a building component is a measure of the time during which it is able to fulfil conditions of stability, prevent the passage of flames and smoke and minimise the temperature rise. This requirement is particularly important where ducts pass through separating walls designed to be fire compartments. The final target is to give enough time to building occupants to exit the building in case of fire.

Appropriate fire protection of ducts is vital to stopping unseen fire spread, as required by national building regulations. The ISOVER U-Protect passive fire protection system for rectangular or circular ductwork can provide up to two hour’s passive fire protection to ventilation and smoke extract ducts as well as one hour’s passive fire protection to kitchen extract ducts when tested to EN 1366-1 & EN1366-8 and assessed to BS 476: Part 24. The U Protect system comprises of slabs, wired mats and accessories

Key Considerations

When using ISOVER products, you need to satisfy yourself that use of the product meets all relevant national Building Regulations and guidance as well as local, national and other applicable standards relevant for your construction or application, including requirements in relation to fire and applicable height restrictions. In addition to the product datasheet, please refer to the following product documents:


Insulation products
Product Name Thickness Range Sizes Lambda
ISOVER U Protect Wired Mat 4.0 Alu1 30-120mm Width 0.6m, Lengths 2.5 - 10m See datasheet
ISOVER U Protect Slab 4.0 Alu1 30-100mm Width 600mm, Length 1200mm See datasheet
ISOVER U Protect Accessories See datasheet See datasheet N/A