window

Describes different types of weatherstrips and reports ageing and deformation test on strips and tests on air tightness and closing force. Concludes that tubular strips provided the highest degree of airtightness in both windows and doors, while angle strips were only slightly inferior in performance. Air leakage was considerably greater for strips of expanded and foam plastics and fibre strips. Tests on ageing properties indicated that special rubber mixtures such as silicone rubber and epdm were preferable to p.v.c.

Presents method for establishing conditions and an acceptance criterion for window air-tightness testing in relation to average energy (heating) saving per winter. Uses wind velocity data from israeli meteorological station of Ashdod to demonstrate difference between various methods of evaluating design wind velocity. Uses 41 different typical dwellings to determine unique criterion for acceptable air leakage under test conditions which ensures average of 1 air change per hour in most Israeli dwellings.

Describes a diagram from which heat losses due to infiltration according to German standard DIN 4701 can be obtained, as well as rate of air infiltration per unit length of crack. By considering several factors the method can be generalised for the case of several windows and doors of varying quality of fit. The method is therefore useful for both the approximate and the accurate calculation of infiltration heat losses.

One cause of these discomfort zones is cold air infiltration through window joints. This can be deflected using a warm air curtain. Describes tests showing that the degree of deflection depends to a large extent on the pulse ratio of the intermixing air flows. Describes chart compiled when experimental results were evaluated permitting determination of volume of air to bedischarged by nozzle convectors sufficient to diminish discomfort zone.

Reports study of air infiltration through experimental windows installed in a normal office building. Air change rate was measured using carbon dioxide as a tracer gas. Pressure drop across window, wind velocity and direction were recorded . Finds that air leakage measured was generally quite different from that which could be calculated. Postulates reason for this is complex process caused by dynamically varying pressure differential across the window, flow occurring through window in both directions simultaneously and to particular experimental configuration used.

Reports results of series of tests on 6 single-family houses to determine rates of overall leakage through windows, doors, walls and ceilings. Uses vane- axial fan to reduce pressures inside house and measure flowrate and resultant pressure differences across house enclosure. Purpose of tests was to assist in eliminating rates of air infiltration in houses.

Detailed analysis of actual space heating requirements shows a much higher consumption in mild weather than predicted. Attributes this mainly to casual window opening, which accounts for 30% of total energy used. This factor will be greater in well-insulated houses where ventilation loss is proportionately greater. Examination of motives for window opening suggests high humidity levels are most likely. The trend to man-made fibres in soft furnishings with low moisture storage capacity accentuates humidity problem.

Gives series of maps and a chart used to specify performance requirements for windows in the United Kingdom in a simple way. Gives maps for the design wind pressure and exposure grades.

Describes behavioural studies of the window opening habits of families in 123 houses to show strong seasonal pattern. During winter, window opening is closely related to moisture levels in the external air. In summer it is most closely linked to outside temperature. Larger families have more open windows. Re-examines ventilation criteria to suggest 3 seasons : deep winter with minimum ventilation for body odour removal ; spring/autumn for controlling moisture and summer for cooling.

Investigates energy balance of centrally heated flat at coastal town of Kijkduin, based on daily figures of gas consumption and ventilation losses derived from meteorological conditions. Studies: 1) pressure difference over the building caused by windvelocity, wind direction and outdoor air temperature; 2) natural ventilation caused by pressure differences over fortuitous cracks and intentional opening of windows, grilles and shafts. Studies possibility of ventilation prediction via mathematical model.