Before the Dehydration
The building, a 500 year old historic building with a vaulted cellar, was first mentioned in historical records in 1509. For the past 250 years – from about 1752 onwards – the building has been operating as a pharmacy, a family owned business passed on from generation to generation.
Before the dehydration the sandstone cellar was very damp. In the lower area of the wall the paintwork was peeling off in many places. The objects stored in the cellar were damaged by the moisture and were partially infested by mould. Relative humidity inside the cellar at 16°C was 85%, which is very high in comparison to the 58% outside relative humidity.
There was a creek running alongside the back of the building and the high waters partially ﬂooded the cellar 1-2 times a year. Additionally, there was an unused well in the cellar, with water in it.
The Aquapol System - Results
The moisture content of the cellar has been closely monitored by periodic follow-up moisture measurements through six different points [M1 to M6] across the building.
As shown by the Moisture Content Diagram, the moisture content in depth has decreased significantly at four of the six measurement points – at 3 internal walls [M1, M2, M5] and 1 external wall [M3].The moisture content of the street side workshop cellar wall [M6] – an earth-touching underground wall with no vertical insulation – has also been reduced by the Aquapol system. The reduction was assisted by the thickness of the wall which attenuated some of the sideways pressure.
The smallest decrease in moisture content was measured at the external wall adjacent to the creek [M4]. However the surface moisture content has reduced from 80% (before) to 50% (after) at the bottom, and from 50% (before) to 30% (after) at the top of the wall. As a result the cellar became perfectly suitable for the storage of various goods with no mould infestation being present.
This is how Dr. Bluhm, the Lead Biologist describes the situation before and after the introduction of the Aquapol system:
Before the dehydration the various objects stored in the cellar got wet, mouldy or rusty. Paper and cardboard became corrugated. After the dehydration the vaulted cellar could be again used for the storage of paper and cardboard without any mould being present.
Mould contamination of the various surfaces have been greatly reduced despite that no additional renovation measures have been undertaken. Mould dangerous to health could not be measured anymore.
Because the building hasn’t been altered by any other renovation works and no ventilation system has been installed, this clearly shows that the excellent results in the dehydration of the vaulted cellar can only be attributed to the installation of the Aquapol system.
To identify the mould species in the basement of the pharmacy and to assess the health risks, a full laboratory microbiloogical analysis has been performed. The analysis has been repeated at 6 monthly intervals until the complete dehydration of the building.
The following mould species have been identified in the basement:
- Aspergillus fumigatus
- Aspergilllus flavus
- Aspergillus niger
- Aspergillus nidulans
- Aspergillus terreus
- Aspergillus versicolor
- Candida yeast
- Cladosporium cladosporiopides
- Fusarium poaoe
- Geotrichnum candidum
- Mucor mucedo
- Penicillium brevicompactum
- Penicillium citrinum
- Penicillium glabrum
- Penicillium notatum
- Rhizopus stolonifer
Some of the Aspergillus moulds on the above list (Aspergillus Fumigatus, Aspergillus Flavus and Aspergillus Niger) were particularly dangerous to health as they could attack the lungs and other internal organs.
Initially, in 2007 and 2008 these very harmful Aspergillus moulds were measurable in large colonies at different parts of the cellar. By 2010 these very harmful moulds could not be detected anymore, they could not survive on dry walls.