Cooking, washing and people breathing are causing damp and mould in Dublin City Council's flat complexes.
That's according to a new report from the local authority.
In 2017, the European Committee of Social Rights found the human rights of tenants had been breached. That was because of living conditions which included persistent damp and mould.
The Irish Times reports that the council plans to redevelop more than 6,000 of its oldest flats.
Howeverr, that could take up to 15 years.
In the meantime it is examining the causes of the mould.
The report says tenant activities such as washing, cooking and breathing, provide the primary sources of moisture that cause humidity indoors.
It recommends not to dry clothes indoors and to open windows.
Independent Councillor Mannix Flynn says it's not good enough.
He said: 'We have children now that are going to have respiratory issues for the rest of their life. And that will be as a result of being in cramped conditions, unsanitary conditions and unfit accommodation in many of the blocks.
'We have a huge crisis coming down the road in terms of dilapidated blocks.'
The report will be presented to Councillors tomorrow evening