Hidden mould in ceiling cavity

My recent investigation into indoor air quality problem took me to a nice Victorian London property. The family living in this rented accommodation has been suffering from respiratory irritation since they moved into the property about four weeks prior my visit. Main concern was regarding their  daughter’s health who was suffering with severe coughs, eye irritation and other respiratory problems.  The symptoms seemed to be particularly severe in the property master bedroom.  It is important to note that the apartment was refurbished just before the family moved in.

During the investigation of the property I have noticed some water damage signs to the walls and ceiling in the master  bedroom. This room has been redecorated couple of weeks before but was already showing signs of water damage. The damage was not extensive and mainly confined to water staining and mineral deposition on the wall surface. The humidity in the house was quite low indicating that the internal humidity is not a problem.

The visual inspection of the property for moulds or did not show any visible moulds in the properly. The air in the property felt clean without any noticeable indoor air irritants. I have taken some samples for chemical contaminants but these turned out inconclusive and only contained some components of solvents and aromatic compounds produced by vegetation of which there was plenty in the close vicinity.

hidden mould

Water damage to external wall

I have also taken samples for indoor air mould spores burden even though there was not visible indoor mould contamination. Further samples were taken from the ceiling cavity of the master bedroom to investigated possible hidden mould above the ceiling.

After the analysis of the mould spores samples in the laboratory, it become immediately obvious that the indoor air quality is seriously contaminated with fungal spores. The indoor Penicillium/Aspergillus counts were in the order of several thousand per cubic meter higher in comparison to less than hundred in the background samples.  The ceiling cavity samples showed presence of significant number of Stachybotrys (Black Mould) spores in the cavity. The building has a flat roof with patio above the master bedroom and it is likely that during period of heavy rain the drainage system can not cope with the a mould of water and localised leaks appear.

Water damage to ceiling with flat roof

Water damage to ceiling with flat roof

The conclusion of my investigation was that it was very likely that the property has visible surface mould in some of the room just before redecoration. The mould has not been removed under controlled conditions and the spores have contaminated the whole property. Furthermore the presence of hidden mould the ceiling cavity of the master bedroom was more than likely.

After presenting the my report to the landlord of the property the family was relieved form the their contractual obligation and has since moved out of the property.

By Tomas Gabor

Link through to Sysco - Nationwide specialists in hazard exposure monitoring
Hi, I have been working in my job as an Indoor Air Quality Investigator for a number of years and decided to share my experience with you. You can find lot of related information on my website toxic black mould
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