Experts to run rule over crumbling concrete blocks in new homes

An estimated 340 homes develop problems with cracked walls and foundations

The blocks have begun to crack and disintegrate, evidenced by cracked cement stucco, or plaster, covering the blocks. Photograph: PA

The blocks have begun to crack and disintegrate, evidenced by cracked cement stucco, or plaster, covering the blocks. Photograph: PA

 

A former senior local government official has been asked to head a panel of experts looking into why concrete blocks used in buildings in Co Donegal and Co Mayo have, in some instances, been disintegrating.

Dennis McCarthy, a former director of services with Waterford County Council, will chair a team of four, which is due to report to Minister of State for Housing Paudie Coffey by the end of May. The other members of the panel, yet to be appointed, will include a structural engineer, geologist, and an expert in concrete block manufacture.

An estimated 300 homes – most of them in northern Donegal, around Letterkenny, Buncrana and on the Inishowen peninsula, together with about 40 in Mayo and a handful in Louth – have developed problems with cement blocks used in their construction.

The blocks have begun to crack and disintegrate, evidenced by cracked cement stucco, or plaster, covering the blocks.

The phenomenon can also affect internal walls, as well as foundations in which blocks have been used.

Manufacture

In extreme cases, if not tackled, the disintegration could make a home structurally unsound and unfit for habitation.

The expert group is expected to say how many homes are affected, to define the nature of the problem and suggest remediation options.

According to Damien McKay, a Donegal engineer who has been tracking the problem, it relates to materials used in the making of the blocks, and the way in which they were made.

It is similar to the pyrite problem and legal action against makers and suppliers is pending.

“The primary cause of this is something called muscovite mica, ” said Mr McKay. “In simple terms what that is, is a very fine flaky dust in abundance in the blocks: with crushed stone, sand, cement and water. It takes a lot of water to make the blocks [containing muscovite mica] and, because of the high water/cement ratio, the block is weak. It’s a bit like the glue is not holding the product together properly.”

Mica Action Group

The issue emerged after the pyrite problem was identified in Leinster and, in October 2013, when Mr McKay talked on Highland Radio about cracks and crumbling concrete blocks, dozens of local homeowners contacted him and the station with similar problems.

The Donegal-based Mica Action Group has been campaigning in the hope of a redress scheme similar to the one offered to people affected by pyrite.

Shane Glackin and his wife live in Inishowen in a 15-year old home. “The blocks are disintegrating,” he said yesterday. “The house is basically uninsurable. This house will disintegrate in time.”

The problem may be more widespread than thought. “I’ve gone out to look at maybe one home in an estate and, as I left, I could see other homes with cracks,” said Mr McKay.

He estimates that €40,000 could be spent rectifying just the external, visible defects caused by crumbling blocks in a 186sq m (2,000 sq ft) home. However, if the foundations were affected and needed underpinning, the cost could be multiples of that.