Fire Safety of Facades

Hazard profile

Unlike an internal fire, a facade fire can spread upward across multiple floors on the outside of a building through combustible insulation, ventilated cavities or composite panels, bypassing the compartmentation inside the building. External thermal insulation composite systems using polystyrene insulation and rainscreen facades with an air gap that can act like a chimney are particularly critical.

Measures

Protective measures include non-combustible or fire-retardant cladding materials, horizontal fire barriers within ventilated cavities, floor-by-floor interruption of combustible insulation layers, and careful detailing around window openings and balconies. During refurbishment of existing buildings, it must be checked whether newly applied insulation systems are compatible with the existing fire protection concept.

Insurance relevance

Facade fires have caused some of the largest property losses in residential and commercial buildings across Europe in recent years and are therefore receiving increased attention in risk assessment. During a survey, risk engineers record facade build-up, insulation type and reaction-to-fire classification as a distinct assessment point alongside internal fire safety.