Describes a series of experiments performed on a residential attic under controlled laboratory experiments to obtain a better understanding of attics and attic insulation. Studies type and level of ceiling insulation, mean temperature and heat flow direction (summer v winter) and ventilation rate Describes the experimental set-up and the weather conditions simulated. Gives details of the mathematical models of thermal performance that are developed from finite difference analyses of the ceiling-insulation system. Compares experimental results with the predictions of these models.
Reviews the mechanism of air infiltration as a background for introducing a procedure that yields more reliable estimates of average infiltration rates through a window unit than do methods currently employed.The procedure is applied to estimating the average winter heat losses through windows in low-rise residential buildings variously located through out the US. Concludes that, regardless of climate, the heat loss attributable to infiltration through the window unit is small compared with that incurred as a result of direct transmission of heat through the window.
Describes several types of door closing or air containment devices for use in industrial buildings, including automatic doors, flexible doors and air curtains. Discusses various forms of air curtain and lists factors that need considering when installing one, such as geographical location, size of door, use of premises, tightness of building etc.
Discusses the Hjortekar project of 6 low energy houses, built as part of the Danish Energy Research and Development Programme. Explains some of the construction details to avoid cold bridges and ensure airtightness. Test results of infiltration air change rates range from 0.02 to 0.12 ach, while other tests show less than 15% difference between calculated and measured transmission heat losses, which range from 70-155 w/degree C.
The author examines the influence on thermal comfort of the air flow inside wall air spaces, on the assumption of a stabilized periodical condition. In these particular conditions an increase of the circulating thermal flow always involves a lowering of the reduction factor, and this increase is greater thelower are the thermal inertia characteristics of the outer wall. Displacement values are found to be mainly influenced by the physical characteristics of the outer wall.
Describes a test method for determining the overall heat loss coefficient of a house. Bases method on the statistical correlation of measured heat consumption with outdoor weather data. Derives a regression equation from the heat balance giving the relation between indoor air temperature, internal heat production and the outdoor weather data. Continuously monitors the power consumption (from electrical heaters) in an unoccupied house, together with indoor air temperatures and outdoor weather data, as solar radiation, outdoor air temperature and wind velocity.
Describes the monitoring over a 15-month period of the heat supplied to and heat lost from an unoccupied house in the grounds of the Cement and Concrete Association. The house was sealed to prevent air infiltration and the windows were covered to eliminate heat transfer by radiation between inside andoutside. Finds that heat losses through the house fabric are proportional to U-values and to the time-averaged temperature differential between the insideand outside environment. Comparison between heat input and measured heat loss shows that cold bridges constitute a significant energy drain.
Describes the ways heat is lost through doors, including flow characteristics, the effect of wind and the effect of temperature difference. Suggests that automatic doors will pay for themselves in terms of energy saved by cutting heat loss through entrances.
Illustrates the building, comprising 24 flats in four storeys constructed in 1957 and heated by an oil fired boiler. Notes the intensive monitoring of the thermal characteristics of the building since 1980, with readings from 600 sensors.
Reports measurements carried out from summer 1979 to summer 1981 in a well-instrumented unoccupied house, and in a less intensive manner in 60 occupied houses of the same construction.
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