The most up-to-date scientific research shows total demolition is the only long-term solution for homes affected with defective blocks, according to one of the world’s leading experts on concrete erosion.
Scientist Dr. Andreas Leemann (pictured above) from the Swiss Federal Laboratories for Materials and Science Technology made the comments to TG4’s investigative programme Iniúchadh TG4 which will be broadcast tomorrow night, Wednesday 6th November at 21.30 pm.
The programme examines the Government’s Enhanced Defective Concrete Blocks Grant Scheme for homeowners with defective blocks (previously referred to as Mica) which was introduced last year. The new scheme offers five remedial options ranging from demolition and reconstruction to partial rebuilding which is a cheaper form of remediation.
“The best solution for the heavily affected homes is total demolition. Just removing the outer leaf can’t be a solution because even if the reaction progresses slower in other parts of the house, like in the inner leaf, it will still proceed so in the end the taxpayer will end up paying more than doing a demolition from the start,” Dr.. Andreas Leeman said.
Iniúchadh TG4’s investigative reporter Kevin Magee travelled to Zurich in Switzerland to interview Dr Leemann about his latest scientific research on the cause of defective blocks, and the best solution.
Dr Leemann’s views are at variance with some of the decisions currently being made by the Housing Agency which determines the appropriate remediation option and grant amount under the scheme which has an estimated cost of between €2.5 to €3.5bn.
Under the terms of the Government’s scheme, the specific amount granted to homeowners varies from home to home, depending on the determination made by the Housing Agency subject to an overall grant cap of €420,000 but this is expected in increase.
Iniúchadh TG4 tracked down one of the first homeowners to avail of the new scheme, Linda Claxton, from Westport in County Mayo. She was awarded €193,333 under the scheme, but after certain costs were deducted, she said he was left with €140,000 to build a new home, and ended up spending €90,000 of her own money to bridge the cost.
“This is a horrendous journey. I don’t envy anyone coming behind me having to do this. I have put 90,000 euro towards this. I went to banks to ask for a loan and was refused. In the end my partner got a loan for me,” Ms Claxton said.
According to Dr Leemann, who carried out a forensic analysis on blocks from infected homes in Donegal and Mayo as part of international research being managed by Geological Survey Ireland, the existence of the mineral pyrrhotite is the real cause of defective blocks, not mica or pyrite which have traditionally been blamed.
“Mica is very easy to spot in the aggregates and probably this led to the assumption that mica is responsible for the deterioration of the blocks. This is nonsense of course. The problem is caused by pyrrhotite in the blocks and it starts to oxidise or rust. When pyrrhotite rusts, it releases sulphur in the form of sulphuric acid, and this causes internal sulphate attack. It’s a natural reaction that occurs so your blocks are expanding. At an advanced stage of the reaction the concrete crumbles and you can take it apart by hand,” said Dr Leeman.
One third of the applications to repair homes with defective blocks in County Donegal transferred over from the old scheme have been downgraded by the Housing Agency from total demolition to other, often cheaper, forms of remediation.
Latest figures supplied to IniúchadhTG4show that of the 353 determinations made by the Housing Agency up to the end of September, 215 were the same as the applicant’s engineer, 15 were for a higher degree of remediation while 120 resulted in the original engineer’s recommended level of repairs being reduced.
Most of the 120 downgrades (106) are from the most expensive option of total demolition to other often cheaper forms of remediation that include retaining certain amounts of the existing blockwork.
Letterkenny campaigner Róise Ní Laifeartaigh from the Mica Action Group, whose own home is infected with defective blocks, told the programme she fears homeowners are being offered lower levels of remediation to save money. Speaking in Irish, she said, “It seems, there is, probably, an mindset there from the State to save money and we think that is that is what is behind the downgrading that is going on”.
In a statement to the programme, the Housing Agency denied suggestions from some homeowners campaigning for 100 per cent redress that the original engineers’ reports to demolish houses had been downgraded to save money.
Asked if this was the case, a Housing Agency spokesperson said: “No. The Housing Agency engages chartered engineers, who are members of Engineers Ireland, to provide appropriate remediation option recommendations in accordance with Irish Standard 465:2018.”
Irish Standard 465is a testing protocol that was developed in Ireland at the request of the Government to assess and categorise the damage to dwellings and aid in the selection of an appropriate remedial solution.
Pyrrhotite is not included in IS standard 465 which is currently under review, but the new enhanced compensation scheme announced by the Government stated that the Housing Agency will “in their analysis and deliberations take into consideration the presence of pyrrhotite.”
Until pyrrhotite is formally included into a new revised standard for assessing damaged homes, the director general of Engineers Ireland, Damien Owens, the body representing engineers told the programme that the Housing Agency should only proceed with recommendations for full demolition.
He said: “Where option one, which is complete demolition is recommended, I think they should proceed with that. If it’s other options other than demolition, prudence would say they should be paused at this time.” “They were looking for mica and pyrite, and they may not have been looking for pyrrhotite. So how can the Housing Agency make a decision on pyrrhotite if there is no mention of it (in an engineer’s report),” said Mr Owens.
The Government’s enhanced grant scheme applies to owners of dwellings in Clare, Donegal, Limerick and Mayo where their dwellings are damaged due to the use of defective blocks. It is estimated that up to seven thousand homes may be affected.
Iniúchadh TG4 – Brící Lochtacha, Pobail Bhriste
Wednesday 6th November 2024
TG4 & TG4.ie @ 21:30pm