A good starting point when discussing this topic is to explain what pyrite is and why it can cause structural problems when present in sufficient quantities.
Pyrite or Iron Pyrite (FeS2) is a common mineral present in many sedimentary rocks. When harmful levels of pyrite are found to be present in building materials, this can cause building defects. In the case of residential buildings, the affected material is the stone fill beneath the ground bearing floor slab. Upward movement of the slab causes floor slab damage, movement of internal partitions that causes cracking as well as external wall damage. Other signs of this problem can be uplift at external door thresholds and doors catching on floors.
The Pyrite Remediation Board defines the ‘at-risk’ period as between 1997 – 2013. Properties built during this period are considered potentially vulnerable to pyrite damage. Remedial work is a major undertaking and involves the removal of the ground floor slab by cutting and breaking it out followed by the excavation and replacement of the stone fill.
We are often asked about the risk of pyrite manifesting itself if a property that was built in 2006 and inspected in 2022 with no signs of pyrite damage being present. Unfortunately, properties built in 2006 can still be affected by this problem and we know of one housing estate in Kildare built at this time where it took 14 years for pyrite damage to become visible. Even subtle cracking can be indicative that the sub-floor fill has excessive levels of pyrite. It is wise therefore to test at risk house even if there is no visible damage. As part of our Pre-Purchase Surveys, properties built between 1997 – 2013 will receive a detailed assessment for pyrite damage specifically the presence of strucural damage such as uneven floors or tile cracking that can be the initial signs of swell in the stone fill.
The problem is not confined to Dublin and surrounding counties. Pyrite is now an established problem in Donegal, Mayo, Limerick and Clare.
If you are concerned about the possibility that you home may be affected by Pyrite call our Galway or Dublin offices and we can arrange to survey your property to assess for structural issues.