5 min read

Enhancing Timber Safety: Sentrin FRI Fire Retardant Treatments

Posted in: Ideas and Advice
12 June 2024

Timber Preservation & Fire Retardant Treatments

Fire Retardant Internal Timber

Sentrin FRI fire retardant treated timber has been pressure impregnated with a humidity resistant, high temperature fire retardant formulation. It has been processed under ISO9001 controlled factory conditions to provide confidence in performance and long lasting protection without further maintenance. Treated timber can meet the requirements of national Building Regulations where Euroclass B or C are required and will significantly reduce the spread of fire, heat generation and smoke generation. These fire performance properties do not compromise critical engineering properties such as strength, durability, corrosivity and hygroscopicity.

Sentrin FRI Logo

Key Points

  • Sentrin FRI treated wood products tested to BS EN 13501-1
  • Designed to perform for the life of the building without maintenance
  • Typical applications: above ground interior applications with humidity < 85%, and external applications when protected from direct rainfall
  • Treatment does not significantly alter the appearance of the timber
  • Pressure impregnation process followed by high temperature kiln drying
  • Avoid reworking treated wood to maintain fire retardant properties
  • Suitable for use with non-corrosive metal fixtures and waterproof adhesives
  • Complies with EU Construction Products Regulation and UK Building Regulations
  • Each consignment includes a treatment certificate confirming fire retardant classification
  • ISO 9001 accredited and Factory Production Control (FPC) certified

Flammability Classifications

Euroclass Transposition to BS476
A1 Non-Combustible
A2 Very limited combustibility
B Class O
C Class 1
D Class 3

User Guide Highlights

  • Treatment process involves high pressure autoclaves and high temperature kiln drying
  • Non-corrosive to metal fixtures and fittings; use waterproof adhesive for glued components
  • Store treated timber in dry conditions to maintain fire retardant properties
  • Treated wood can be painted with standard coating systems; test samples to ensure performance
  • CE marking and compliance with UK Building Regulations for construction products
  • Each consignment includes a treatment certificate confirming fire retardant classification
User Guide Image

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