English

In France, most of the ventilation systems in dwellings now consist of exhaust vents linked up with a fan, and air inlets. A survey conducted by the CSTB shows that actual ventilation rates are frequently different from prescribed values and that a lot of problems encountered are related to occupant behaviour, - The duration of exhaust flowrate peak value was measured ; it was shown that this duration was dependent on the kind of command and its location in the room. - draughts through air inlets were a major concern. - a lots of air vents did not operate correctly because of fouling.

In this paper we approach the subject of ventilation and occupant behavior in multifamily buildings by asking three questions: 1) why and how do occupants interact with ventilation in an apartment building, 2) how does the physical environment (i.e., building characteristics and climate) affect the ventilation in an apartment, and 3) what methods can be used to answer the first two questions. To investigate these and other questions, two apartment buildings in Chicago were monitored during the 1985 - 1986 heating season.

An energy efficiency monitoring programme was carried out from 1984 to 1986 by the South London Consortium Energy Group, United Kingdom Department of Energy, with assistance from British Gas, Watson House, as part of a demonstration project funded by the United Kingdom Department of Energy, the EEC and SLC Energy Group. 18 occupied low energy houses were thoroughly instrumented in order to monitor energy usage and occupant hehaviour.

After years of intensive studies on indoor air pollution sources, pollution levels, condensation effects, building airtightness, and air change rates, we are now at the point to discover that no solution whatsoever to the ventilation problem is possible if compatibility with user comfort and user habits are not properly taken into account. User compatibility of aventilation strategy under todays conditions in dwellings must in fact be understood as a requirement equivalent to the purely functional ones of pollutant removal and of economy.

The buildings built according to the latest construction technology aiming at energy saving are as tight as possible. The ventilation of a tight building has to be completely mechanical (supply and exhaust a i r system). The heating of the building can also be included in the mechanical ventilation system with small additions. The new warm air heating system developed at the Laboratory of Heating and Ventilating of the Technical Research Centre of Finland is therefore called ventilation heating system.

The role of the occupant in buildings energy use has been evident in studies in many countries. Our experience since the early 1970's has indicated that energy use can vary by at least a factor of two solely on how the occupant operates the house or apartment. This often involves window use. For example, window and door openings, to cool an overheated dwelling, can take place at any time of the year. This paper describes work at Princeton which measured occupant ventilation behavior, and which provided feedback in an attempt to modify behavior.

A balanced ventilation system with heat recovery was designed and installed into an 11 storey prefabricated block building. Monitoring of the system operation was accomplished during a year. Operational characteristics, quantified energy saving, indoor climate parameters and the effect of occupants' behaviour on those were determined and analysed. Temperature runs during durable window opening and cooking periods were monitored and on the basis of the results comparison between the new experimental and the traditional reference system was made.

The occupants' behaviour is one of the parameters which has the greatest influence on the air change in the dwelling. This applies both to naturally and to mechanically ventilated dwellings. On the basis of continuous measurement of the air change in 25 dwellings, the relation between the ventilation system and air change and between the number of occupants and air change is discussed. The air change in the 25 dwellings has been measured for a period of about one week during occupancy. The measuring principle applied is "the method with constant concentration of tracer gas".

Within the framework of the national research project "Ventilationin Housing Construction", studies on occupants ' ventilation behaviour were conducted in a demonstration building in Duisburg- Neumuhl (Federal Rep. of Germany) which also formed part of the project . Analyses were based on values measured from Jan, 1 - Dec. 31, 1984 in 24 flats with identical ground plans, all of which were equipped with mechanical ventilation systems.

20 low-income family houses were studied for Air Changes per Hour and Equivalent Leakage Area as measured by the Blower Door Test during the winter of 1985-86. The residents of 10 of these homes were given instruction on air sealing techniques and were provided a "starter kit" of retrofit materials. Upon retesting, these 10 homes showed no improvement in either ACH or ELA,indicating either a lack of interest on the part of the householders in making their homes more airtight, or an inability to do so based upon insufficient information or physical limitation.