https://www.bbc.com/news/world-europe-68378968Did cladding enable the fire to spread?
Experts have suggested that cladding on the outside of the building could have been a factor in enabling the fire to spread rapidly.
Cladding is added to the facade of modern buildings to keep the weather at bay. Behind the panels there is usually an air space to help insulation and prevent damp.
Esther Puchades, vice president of the College of Industrial Technical Engineers of Valencia, told Spanish news agency Efe she had previously inspected the building.
She said its exterior featured a
polyurethane material, which is no longer in wide use because of fears over flammability. It also has an
aluminium covering."The reason the [building] burned so fast is because of this type of cladding," she told Spanish media.
The cladding has been described by experts as effective for heat insulation but the ventilation, or gap, between it and the covering means it can be highly flammable.
Luis Sendra, of Valencia's architects' association, said this can cause a "chimney effect", allowing fires to spread more quickly.
The specific type of cladding on the buildings in Valencia is still unclear, and some types of cladding are more flammable than others.
A 2007 promotional video by the building's developer mentioned the "innovative material" used to clad the building's exterior, which
passed "rigorous quality checks".The issue of flammable cladding gained prominence in the UK after the 2017 Grenfell Tower disaster, in which 72 people died when a tower block in west London caught fire.