Defective concrete blocks in homes in Co Donegal are failing because of pyrrhotite and not mica, according to a study published in leading international journal Cement and Concrete Research.
There could be 2,000 legal actions, with a total value of €550 million, concerning mica-affected concrete blocks before the end of the year, it has been claimed in High Court proceedings. Some 1,100 cases have already been issued.
They are suing over damage from concrete blocks and similar products containing mica that were used to build their home between 2005 and 2008. Mica is naturally occurring in rocks but, when used as an aggregate, makes concrete weaker over time.
However, a study conducted by researchers at Empa, Switzerland, Ulster University, UK, and the TA Group suggests that defective concrete blocks in Donegal are failing because of pyrrhotite and not mica.
Image credit: The Irish Times