Concerns regarding damp in a dental practice
Our client based in Margate contacted us with concerns regarding damp in their dental practice. They instructed us to carry out an indoor air quality assessment in relation to biological contaminants.
The dental practice is a three storey terraced townhouse which consists of four levels, the ground and basement levels of which are affected by dampness. The ground floor consists of one dental surgery, reception/waiting area and access corridor with a stairwell to the lower and upper levels. The basement consists of another dental surgery, practice managers office and two store rooms.
Were fungal contaminants present?
At the time of our assessment the fungal spore trap samples shows that the overall concentration of airborne fungal spores in the indoor areas was elevated in comparison to the existing environmental background. The spore trap samples collected in the habitable areas of the property were dominated by Penicillium/Aspergillus type of spores with minor presence of other environmental fungi. The collected environmental background sample was dominated by basidiospores followed by Ascospores. The Penicillium/Aspergillus group is elevated in surgery 1 which possibly indicates a hidden indoor source. A minor presence of fungal groups is typically associated with water damage in buildings such as Chaetomium and Stachybotrys was identified in both indoor samples.
What did moisture mapping reveal?
When visually inspecting surgery one in the basement, our surveyor found that the moisture level was elevated to the full height of the wall however there was no noticeable damage to the decorative finish. On the wall around the window frame there was evidence of water staining and when tested it showed elevated moisture levels. The lathe plastering on the ceiling above the window also showed elevated levels of moisture. Although these areas had conditions favourable for fungal contamination, there were no signs of it in this room.
Next on our list to inspect was surgery 2 on the ground floor. We thoroughly inspected all areas of the room including the ceiling cavity. There were no signs of water damage or fungal contamination in the ceiling cavity. The external wall in the room showed elevated moisture levels which originated around the window. The internal walls had evidence of water damage and staining to them and when investigated further they showed elevated moisture levels to the full height of the wall.
The installed cabinets on the wall showed some minor signs of water damage and rusting to hinges but no signs of fungal contamination. The areas behind the installed cabinets were free from water damage and fungal contamination. The floor in the room in the area of a former chimney, which now houses a filtration pump, had high moisture levels although the corresponding areas of the ceiling in the room below shows no signs of elevated moisture so appeared to be contained.
What did we recommend our client?
Our indoor air quality assessment showed that the concentration of fungal spores in the indoor air were elevated in comparison to the existing environmental background sample. This means that the indoor air quality with respect to fungal contamination can be described as poor. Elevated levels of Penicillium/Aspergillus in both surgeries could be indicative of hidden fungal contamination within the ceiling cavity in surgery one therefore we strongly recommend this to be investigated further as our surveyor could not do this without causing significant damage to the floor of surgery 2.
Surgery 2 is currently affected by water penetration through the building envelope in the areas of the window and in the internal wall with the adjacent property. Our surveyor believes that the damp issues are likely to be long term and of mostly cosmetic nature. He recommended our client to line the internal wall with an impervious cover to prevent future staining. In the absence of visible water damage and fungal contamination it is recommended to monitor this area. No service leaks were identified in the surgery.