English

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.

Occupants can significantly influence both the heating energy requirements and the indoor air quality of a building by opening and closing doors and windows. If the effects of these actions are to be accurately estimated, both the quantity and character of these exchange flows must be determined. In this paper, data on gravity-driven exchange rates through open doors obtained from field experiments at the Alberta Home Heating Research Facility are compared with laboratory model simulations and theoretical predictions.

The effects on ventilation behaviour of inhabitants in residential buildings have been investigated as a part within several years' German R and Dprogramme. The investigations have shown that the ventilation behaviour seems to be dominated by traditional behaviour patterns, e.g. ventilating bedrooms, and subjective impressions. There is only a modest correlation between window opening and needs for indoor air quality and energy conservation. Up to nowmost of the inhabitants do not assess correctly their own window opening behaviour.

Subjects covered include: problems of radon, formaldehyde build-up in the home, residential indoor air quality, effect of moisture on other pollutants, epidemiology of indoor air problems, setting standards for recognising harmful concentrations in homes, the effect of retrofit conversion measures, thepublic's perspective.

Existing models for predicting air infiltration account for three dominant variables, namely envelope leakage characteristics, indoor-outdoor temperature difference and wind speed. Building shape, wind direction and sheltering, also influence the wind induced component of air infiltration. In this report, these variables are examined analytically and experimentally using wind tunnel data and field infiltration measurements. A sensitivity analysis of a power law infiltration relationship reveals that these factors are most significant at small temperature differences.