Ventilation rates in two test home were measured using helium as a tracer gas. Pressure differences across the exterior walls of the house were recorded using pressure taps. Gives results for air infiltration tests and the calculated air infiltration. Finds that during summer air infiltration rates varied approximately linearly with wind velocity. During the winter, the pattern and extent of air infiltration were influenced by both house stack action and furnace operation.
Reports investigation of air change rates in two residences using helium as a tracer gas. Gives results of measured air change rates, wind speed and direction and internal to external temperature difference. Uses statistical method to compare results from the two residences and concludes that temperature coefficients were statistically different but that wind coefficients were not. Finds high dependence of infiltration rates on indoor to outdoor temperature difference and that values for air leakage obtained from current methods of estimation were lower than those actually experienced.
Describes retrofitting a wood-frame residence in three stages to reduce its energy requirements for heating and cooling. The three retrofit stages comprised reducing air leaks; adding storm windows; and installing insulation in the floor ceiling andwalls. The house was extensively insulated to evaluate energy savings and changes in air infiltration rates. Concludes that retrofits produced only marginal reduction in air infiltration rates and attributes this to the original tight construction of the house.
Describes retrofitting a wood-frame residence, having only limited insulation in the attic, to reduce its energy requirements for heating and cooling. The three retrofit stages comprised : reducing air leaks ; adding storm windows : andinstalling insulation in the floor, ceiling and walls. The housewas extensively insulated to evaluate energy savings and other performance factors. an economic model was used to evaluate the cost effectiveness of the retrofit options.
Describes the results of an investigation carried out to determine the rate of fresh air infiltration that is experienced during the winter in a modern air conditioned office building. Six different methods were employed to estimate the rate of infiltration through the building, four by direct measurement and two by calculation. The methods of direct measurement were,tracer gas decay, measured air flow through one floor, measured air flow through one air conditioning unit and measured change on power demand.
Reports investigation to devise a simple method for measuring the airtightness of buildings which will provide clear results in conformity with a definite standard, swedish building regulations 1975. Consists of two parts; field measurements comprising overpressure and tracer gas methods using nitrous oxide, and a theoretical calculation of the infiltration of air into a building. Shows that a test method to measure the airtightness of buildings can be developed.
Describes the original series of case studies made by Dick and his associates between 1949 and 1951. Reviews current activities, divided by building types and discusses the problems and needs of future work. Recommends research and development projects and project areas.
Refers to earlier work by Mattingly, Peters, Harrje and Heisler which indicated the possibility of reducing air infiltration by using sheltering devices such as fences, neighbouring buildings and trees. Reports use of wind tunnel air infiltration model to explore the effect of trees in a windbreak on a model home. Presents results of tests determining the effect on wind-induced air infiltration of the variation of various windbreak layout parameters. Introduces concept of turbulence generation as the mechanism of tree wind sheltering.
Analyses the problem of air management in energy conserving passive solar houses and discusses cost effectiveness of various alternative scheme. Use of polythene sheeting to form anair-tight membrane aims to reduce uncontrolled ventilation rate to 0.05 air changes per hour. Discusses problem of indoor air pollution and suggests adding venting windows and air-to-air heat exchangers. The need for internal air circulation is answered by ceiling fans or a central forced air system.
Gives method for calculating infiltration of a building due to wind and stack effect. Uses equations from ASHRAE guide of 1958, but resolves wind vector into horizontal and vertical components and takes the angle between wind and ground into effect. Method is used to calculate infiltration due to wind for a given building of height h at a distance d from the nearest building with height c and a sample calculation is given