English

Describes exterior walls of metal studs and gypsum board, used as infill walls in frame construction of industrial, commercial and high-rise residential buildings. Discusses problems of high thermal conductivity of such walls, and the application of a vapour barrier to reduce air leakage.

Reports tests of the air leakage of 24 houses made using a fan to depressurize each house. Gives a table of results including indoor humidity, air-particulate levels, energy consumption and comfort conditions for each house. Comparison of test results with calculated values for air leakage suggests than doors and windows account for only a fraction of the total. Finds some correlation between indoor humidity, air-particulate levels and leakage.

Describes results of measurements of air leakage, surface pressures and air infiltration for several conventional and energy efficient houses located throughout the United States. The measurements are compared with predicted infiltration obtained from a simple model combining measured air leakage values and average surface pressures. It was found that within limits therewas reasonable agreement between measurements and predictions. Particular features of the energy efficient houses which reduce air leakage, and therefore air infiltration, are described.

A multitude of design strategies are available to achieve energy-efficient windows. Opportunities for improving window performance fall into six groups: site, exterior appendages, frame, glazing interior accessories, and building interior. Design strategies within these groups can improve one or more of the six energy functions of windows : solar heating, daylighting, shading, insulation, air tightness and ventilation. Gives 33 strategies for energy saving. Includes information on weatherstripping windbreaks, shutters, multiple glazing and many others.

Describes the use of mechanical ventilation coupled with heat recovery devices in residential buildings to maintain acceptable indoor air quality and conserve energy. Gives tables showing the energy saving possible with a heat exchanger.

Suggests use of an electron capture detector for the routine estimation of the SF6 content of a mixture of gases without preliminary chromatographic separation. Gives chromatogram illustrating method.

Describes Lawrence Berkeley Laboratory's air pollution research project, giving the main goals, parameters to be measured and instrumentation. Describes studies, using an experimental room of 27 cu.m., which measure the emissions from a gas stove operating under air change rates of from 0.25 to 10 changes per hour. Gives graphs of results. Finds that gas stoves generate extremely high concentrations of pollutants when the air change rate is less than one per hour.

Discusses the two methods for calculating air infiltration given in the ASHRAE handbook. These are the air change method, a gross estimate based on the number of windows and doors in each room, and the crack method based on measurements of flow through the cracks around windows and doors. Presents comparisons of tracer gas measurements with calculations by both air change and crack methods for test houses in California and Minnesota. Find agreement is adequate for sizing equipment but that the crack method underestimates infiltration at low wind velocity.

Increasing use is made of open front or cold confinement buildings for fattening beef cattle. Reports model study of an open front beef confinement building a) to evaluate the effects of ridge vent design on airflow characteristics and temperature and b) to determine prediction equations forthe relationship between wind velocity and outlet velocity. Reviews literature on the subject. Compares results with previous studies. Discusses relationships between outlet velocity, wind speed and temperature difference. Recommends open and baffled ridge vents.

Discusses five different models for predicting air infiltration. Presents a new model developed at the Institute of Gas Technology. The model is based on the results of tests to obtain the contribution of the existence of a chimney, and furnace operation, to house air infiltration. Reports verification of model by simulating results from 23 test homes. Concludes that model simulates with reasonable accuracy the measured values for a single-storey home equipped with an oil-fired central furnace.