mould

A kitchen is one of the major moisture producing areas in a dwelling. In order to prevent condensation and mould growth the relative humidity should not be too high. This paper describes a set of experiments comparing methods of kitchen ventilation and their effectiveness at moisture removal. The three methods of extract ventilation were: 1. A mechanical extract fan of extract rate 60 l/s 2. A passive stack ventilation system 3.

In recent years, poor indoor climate has increasingly been seen as the cause of health problems for building occupants. Today, there is good evidence in some areas why such problems arise. Unhealthy substances given off by various building materials, the existence of mould and general air pollution are the main causes. In general, the most important way to remedy the problem is improved ventilation. Poor upkeep and maintenance have led to a decline in the performance of existing ventilation systems.

The Dutch "E'novation" program is a national demonstration program in which dwellings with high energy consumption, moisture and mould problems and poor indoor air quality were renovated, with special attention to the selection of the heating and ventilation systems, thermal insulation and the buildings' physical details. A number of indoor air quality parameters were monitored before and after renovation, showing an important improvement in the indoor air quality. Moreover, total energy consumption decreased by 33%, which meets the targets of the Dutch National Environment Policy.

A "fungal index" is proposed as a new climate parameter for the characterization of the indoor environment. The index quantifies the environmental conditions in relation to the ability of fungi to grow by means of the response of a xerophilic fungus Eurotium herbarioriun. The growth response of this fungus was found to be climate-dependent. The indoor environment in a residential building in Japan (1991-1992) was quantitatively assessed by this approach. In the assessment, the variation in microclimate, which differs greatly within and between rooms, could be demonstrated.

Intermittent heating patterns, characteristic of Israel and other countries with a mild winter enable energy · conservation at the expense of very high peak energy consumption; · very low levels of thermal comfort; and surface condensation and mould growth problems. The paper summarizes a research project which included analysis of total daily energy consumption, partial energy during evening (peak) hours, weighted cost of total energy, improved thermal comfort, internal surface temperatures -of the external envelope, and surface temperatures of partitions.