Fire Safety Guidance EWI external insulated rendered wall installations

External Thermal Insulation Composite Systems (ETICS), also referred to as EWI (External Wall Insulation), have been used in the UK for many years. Many of these systems use combustible insulation materials (such as polystyrene or PUR insulation).  We’ve received a number of enquiries regarding Fire Risk Assessments for EWI buildings, along with questions on fire stopping and compartmentation. We’ve undertaken some research and have put together a list of points you should consider when reviewing the fire safety of EWI cladded buildings.

Please consider the following Top Tips guide, this isn’t a complete guide, however it should help you consider some of the risks of combustible insulated and rendered buildings:

  1. Identify which type of insulation material has been used, if it’s a combustible material then we suggest you consider the points below. This applies to locations without a cavity between the insulation and building.
  2. Review your Fire Risk Assessment to include external cladding, make sure it’s a type 3 or 4 (type 1 doesn’t cover much more that the evacuation stairwell)
  3. Speak to the original EWI installers/manufacturers for copies of design records, construction details, structural calculations, specifications, system certification for the EWI system. Make sure you are competent to review this information – or ask someone who is.
  4. Did the design, at the time of installation, meet the current best practice standards?
  5. Is there a suitable number of mechanical fixings for the render insulation and fire barriers, not simply relying on adhesives?
  6. Have mechanical fixings been subject to pull out tests?
  7. Are horizontal fire barriers (min 200mm high) positioned at every floor level and vertical fire barriers positioned at compartment wall locations?
  8. Are Fire barriers fitted around each window opening?
  9. Have you installed fire barriers or non-combustible sleeve installed around heating vents? See our range of fire stopping products here
  10. Are intumescent grilles fitted over airbricks and vents, and collars over pipes passing through the walls?
  11. Site surveys might be necessary to confirm the design standard, location of fire breaks, mechanical fixings and the current condition of the EWI installation. Sections of the render could be cut away (then reinstated) to locate fixings/barriers
  12. Undertake regular and recorded visual inspections of EWI systems to check the condition, making sure all fixings secure and not corroded, cracks identified, holes filled etc.
  13. Could fire spread from an external source – such as vehicles or waste skips? If so, re-position them further away.
  14. Have there been any problems at the building – be on the look out for local arson attacks – as additional precautions might be appropriate!
  15. We suggest you provide information on your building construction/insulation materials within your emergency plans boxes – such as the Gerda Boxes here

We hope you find this useful, we aren’t fire safety advisors (this list is produced using freely available internet research) we do however provide a range of fire safety products which will help you achieve fire safety compliance  – have a look for yourself