According to the report, concrete contains calcium hydroxide, an alkaline chemical to protect the steel enforcement.
The chemical is affected by carbon dioxide in the atmosphere.
This creates a dilute carbolic acid and corrosion of the concrete.
It is made worse by rainwater, ice and snow which causes the exposed steel to expand and contract, which forces away the outer layer of concrete in a process called spalling.
Scaffolding surrounds Ashford Police Station to protect people from falling concrete debris from the cladding.