The following article comes from the UK and is titled, "Toxic Mould and Construction Defects Harming Public Health." This clearly demonstrates that the issue of indoor air quality is an international one.
The quest for reduced carbon emissions from buildings – and therefore a lower level of air changes – has in recent times created a general increase in ‘building tightness’: new and restored buildings fail to ‘breath’ properly, leading to a general moisture build-up which in turn results in the health concerns of mould and rot or decay. Typically, Building Forensics has found that the application of new building tightness conditioning such as BREEAM, LEED and part L of the Building Regulations, coupled to poor construction management, is increasingly causing such building defects and health issues.
Jeff Charlton of Building Forensics states: “Building Forensics has found increasing evidence that construction management is failing to control quality standards or, indeed, even to comply with manufacturers’ or architects’ design or installation requirements. Worse still, we’ve found that few surveyors or inspectors have the equipment or training to undertake non-intrusive investigation or to be able identify hidden defects such as missing insulation, thermal bridging and the presence of toxic chemicals.”
He continues: “And Building Forensics is further finding that facility managers are increasingly mis-diagnosing design and build faults which cause condensation or pooling and mould. They wrongly attribute these symptoms to presumed leaks which insurers then wrongly pay to fix. And meanwhile the health problems continue to get worse.”
The combination of high cellulose materials and misuse of vapour barriers, thermal bridging from poor or missing insulation or failure to seal the building envelope properly can result in the growth of toxic mould such as Penicillium, Tricoderma and Stachybotrys.
While visible mould is a good indicator of the health risk, it should be recognised that the moisture required for mould growth, sometimes from leaks but usually from condensation, often occurs out of sight in voids or behind plasterboard cavity walls. The problems start with the building or renovation of buildings with no regard to the historic knowledge that buildings need to breath and remove moisture, especially in a cold wet climate.
And as was shown in US timber frame construction 10 years ago, identifying the problems generally requires more equipment than a standard two pin wood moisture meter and current inspection techniques.
Jeff Charlton is available for comment and interview on the findings of Building Forensics, and more information on typical health concerns and construction defect can be found at the Building Forensics website.
- ► 2011 (436)
- ▼ February (9)