Hens H
Bibliographic info:
10th AIVC Conference "Progress and trends in air infiltration and ventilation research" Espoo, Finland, 25-28 September 1989

Annex 14 -Condensation and Energy- started in April 1987, with a take of meeting in Utrecht, The Netherlands. The annex itself was born after a moisture-workshop in September 1985 at the Laboratory of Building Physics, KULeuven, Belgium. Motivations from the beginning were a widespread feeling that badly balanced energy conservation actions in the seventies and early eighties had increased the number of moderate to severe mould complaints in dwellings, with all possible nuisance, health and financial consequences, the fear that this could enhance each energy conservation policy, and the conviction that the mould reality was socially inacceptable, especially because of the problem being most pronounced in the low income housing sector. Nevertheless, a convincing argument for the first motivation was and is difficult to find. A Belgian enquiry of 1986 in 5000 social dwellings showed a mould problems level of some 20% [1]. The Netherlands reported f a same percentage in the subsidised building market [2]. The U.K. spoke of + 25 to 30 % of dwellings affected in the low income, rented housing [3]. Only this year, a more convincing argument was advanced by the U.K., where a new enquiry showed a net increase in mould and a clear growth in severe mould problems (Oral information at the Leuven meeting, may 1989). But still here, the question remains if that isn't a result of 10 years conservative government, with a lower interest in overall social policy, rather then of a conscious but badly balanced energy conservation policy. The paper starts with focusing on the so called first order surface condensation theory. Then a short shift to the energetical links follows. After that, the organisation and progress of the work is explained, and we end with an overview of the results.