window opening

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.

Due to the fact that loss of heat due to transmission is on the decrease, the loss of heat due to ventilation is becoming more important. Heat recovery units must be put into use to decrease the heat loss due to ventilation. If mechanical ventilation systems are used to create a minimum air change rate, air-tight windows are necessary - but if no ventilation grilles are used they are out of place.

The use of heating and ventilation was measured in several flats to find the relationship between the two. Measurements were taken in 9 flats in a 6-storey block in Berlin, with various types of ventilation system. Two flats remained uninhabited to serve as a comparison. The duration of the opening of windows of the individual rooms lastd on average up to 15 hours per day during the whole heating period. The tenants' own evaluation of the duration of airing differed immensely from this result.

This paper examines the excess ventilation losses arising from window opening behaviour by occupants and using data from a number of sources relates these losses to the outside air temperature. These excess ventilation losses alter the shape of the total heat loss predictions and bring these more into line with the energy consumptions measured. Excessive ventilation by open windows is shown to negate the benefits of increased fabric insulation.

If the energy losses due to ventilation have obviously become an important problem since the energy crisis, there is still a lot to be done with respect to the behaviours. Previous research has given results about the share of venti lation losses i n the energy balance, and the rational reasons to introduce fresh air into the house. Annex VIII is specialized in the attitudes of the inhabitants, in their habits with regard to ventilation and even in their apparent irrationality.

Discusses indoor occupancy factors, including window opening habits, opening of internal doors, time spent indoors and patterns of occupancy, for inhabitants of the United Kingdom.

The effects of operating unvented appl i ances and opening windows on indoor pollutant levels and air exchange rates are being studied under the sponsorship of the Gas Research Institute. The study is being conducted i n an instrumented, well-characterized bilevel house located near Washington, D.C. Air leakage due to window openings is characterized by pressurization measurements and the air exchange increment is characterized through tracer gas measurements. Two unvented space heaters, one radiant and the other convective, are operated singly and in combination with a gas cooking range.

Ventilation can be advantageous as opposed to adventitious and, with careful building design, can eliminate the need for air conditioning in summer. This paper discusses the general principles of design for ventilation, inparticular the removal of excess heat, and presents two examples of buildings designed to eliminate air conditioning. One is a deep plan office block, the other an exhibition hall. In both cases ventilation models featured strongly in the design.