Gary's premises was 18 years old. For as he could remember, there had been an unpleasant musty odour in one room. His inspections, as well as those by several builders, had not found either any visible mould growth or signs of moisture incursion. As he was considering renovating the building, he wanted to determine whether or not mould proliferation was present so that, if necessary, he could replace the affected materials as part of the renovation process. Building Wellness was therefore asked to conduct air and surface mould sampling throughout the building.

Test results

While the building appeared to be in good condition and ventilation seemed to be adequate, laboratory analysis of the samples found that there were extreme levels of mould proliferation in both the floor and the roof space of the building, as well as in the heating duct of the room in which the odour was noticed.

While the chipboard floor had not been flooded since the building was completed, it was subjected to the weather for 12 months during a pause in the construction process. During this time, it became saturated with water and warped significantly. When building recommenced, it was air dried, then sanded to make it level again. As it was not structurally dried, it was thought that environmental moulds that were present in the wet floor continued to proliferate when construction continued. The presence of this mould would explain why the odour had been noticable since the building was constructed.

As there was no history of roof leaks, it was thought that the high mould levels in the roof space may have been associated with condensation on the underside of the metal roof. This moisture may have resulted in mould growth in the ceiling insulation and in a fine layer on the underside of the roof.

Recommendations

It was strongly recommended that the floor of the building be replaced, as mould was present throughout the entire mass of the flooring material. It was also recommended that the carpet, which had been in direct contact with this floor, be replaced.

Gary was advised to have a HVAC specialist inspect  the heating system to identify the source of moisture that was responsible for the mould growth in the duct . Once this source was eliminated, the system could be treated for the existing mould presence.

Finally, further testing was recommended to determine the location of the mould proliferation in the roof space. It was also suggested that Gary consider insulation for the roof to reduce the likelihood of condensation there in the future.