Structural inspections at Heathrow and Gatwick airports have uncovered buildings with collapse-prone reinforced autoclaved aerated concrete (Raac).

Both airports are addressing the safety concerns related to this material.

Heathrow is implementing "remedial steps" and developing a long-term safety plan,

while Gatwick maintains a register of Raac-containing buildings and conducts regular inspections with no immediate concerns.

Raac is a lightweight alternative to traditional concrete, but recent failures have raised safety concerns, leading to the closures of public buildings like schools and hospitals.

Both airports prioritize safety, with Heathrow stating it's their top priority and Gatwick highlighting their ongoing monitoring efforts.