Overview on insulated panels

Insulated panels (also known as ‘composite’ or ‘sandwich panels’) have been the subject of debate for a number of years. Despite concerns due to the confusion between panels used for external and internal applications, insulated panels used for the external roofs and walls of buildings have performed well in the relatively few fires in which they have become involved. See fire case histories.

Designers, insurers, the regulations legislators and even the fire services now separate insulated panels into two very distinct groups:

The largest group are panels designed specifically as roofs and walls for the external envelope of buildings. Analysis of major fires since 1991 has shown that in hardly any instances have these external panels been involved in fires except after the fire has reached the fully developed stage. For the latest research into major fires – click here. The second smaller but significant group are panels designed for internal use only as linings, partition walls and ceilings, predominantly in the food and cold store industries. It is this application of panels and the polystyrene insulation material used in their construction that has led to numerous large fire losses and has been the specific area of concern.

Differences in panel types
Insulated panels are a pre fabricated insulated system delivered to site ready for installation, typically having two metal skins bonded to an inner insulation core. They are an inexpensive, efficient building system, conforming to building regulations and having superior insulation and low maintenance qualities.

External roof and wall panels are in widespread use in modern buildings in the UK. They are designed with joints that are weather and airtight and are securely fixed at regular intervals to the main structure of the building. This enables them to withstand wind, snow, static loads and other forces and also prevents collapse in fire.

Internal panels are generally structurally weaker systems designed for ease of installation / demountability and to satisfy the thermal insulation and hygiene demands of the cold store and food processing industries. Panels used to be free-standing or simply fixed at floor and ceiling level but are now fixed to ensure against the potential risk of collapse in fire.

Back to top. Also in this section:
Panel behaviour in fire  |  Findings of fire research on major fires  | 
Fire research – case histories  |  Certificated panels and testing