English

BSTRACT Describes test made to determine air flow through entrances to a multi-storey building. Temperature and pressure differences across entrances and outside wind speed were recorded and flow through doors studied using laboratory scale models. 

Analyses theoretically the natural ventilation of buildings. Derives fundamental formula for the amount of ventilation due to temperature difference from Bernouilli's theorem considering buoyancy. Explains physical meaning of friction loss and theneutral zone, derives pressure distribution due to wind from the shape of buildings and the location of openings. Obtains total expression for amount of ventilation due to both temperature difference and wind.

States direct observations of wind effects on real buildings are necessary for the development of reliable information for wind load estimation. Their essential role is to provide data for the guidance of systematic wind-tunnel investigations. Briefly reviews instrumentation used in a particular tall building and the methods employed to interpret the measurements. The review illustrates the potential, as well as some of the problems of field measurements in providing practical information about wind loading phenomena. Summarizes results and discusses their implications for design.

Describes pressure method for testing whole houses for air leakage. States main advantages compared to tracer gas technique are that equipment is inexpensive, easy to handle and so well adapted to routine tests. The house is pressurized using a powerful fan and the flow through the fan is equivalent to the leakage through the building envelope at given pressure. Summarizes measurements made on test houses. and shows use of thermography to detect leaks. suggests use of pressure test to estimate the natural ventilation of a house.

Notes importance of air motion in shielded buildings in hot and humid climates. Describes wind-tunnel investigations on shielding effect of buildings for a group of buildings comprising parallel rows of identical blocks. Also considers influence of cross-ventilation through shielding building and variations in relative heights of the buildings. Discusses variation of wind speeds inside shielded building related to its distance from shielding building. gives optimum distances of separation for maximum and minimum shielding effect.

The significance of air tightness on building performance and the factors affecting the air leakage performance of the building enclosure are discussed. the ability of the ASTM standard air leakage test method to check the quality of design and manufacture of factory-assembled walls, windows and doors as well as the inability of the method to provide the building designer with quantitative air leakage data for calculating heating and cooling loads and designing smoke control means is also discussed.

Reports on the air leakage characteristics of the exterior walls of eight multi-storey office buildings in Ottawa. Results of the measurements taken are given and a method for calculating infiltration rates caused by stack action has been developed andis applied to heat loss calculations using the measured wall leakage values.

Describes portable air leakage apparatus capable of measuring the air infiltration of whole dwellings directly on site by the pressure method. Main assembly consists of a flow measurement duct and electric fan. Describes test procedure and gives air leakage curves for an ordinary semi-detached house and an experimental house. Finds that doors and windows account for a surprisingly small proportion of total leakage.

Part of an extensive research programme being carried out also in Denmark, Finland and Sweden. Describes 75 window tests and gives diagrams of air flow and rain penetration apparatus. Proposes tentative evaluation curves for air penetration of windows of a stringent kind suitable for a severe climate. For air pressure of 30-40 mm of water, an 'acceptable' air flow is about 30 m.m. per hour per test window, with 'good' at about 20 and 'excellent' about 11. The curves are shown graphically.

Proposes a method for measuring the rate of air change in factories using ammonia as a tracer gas and measuring its rate of decay by a colorimetric method. The advantage is that extremely small quantities can be detected. The method is cheap, easy to use, reasonably accurate and unobjectionable to the occupants.