Describes laboratory test performed on four steel swing windows and one steel double-hung window to determine leakage rates at different values of pressure and humidity. Concludes there is a wide variation in leakage rates of well constructed windows. Test results depend on the method of closing and latching windows, leakage for steel swing windows is found to differ when determined with ascending and descending pressure differences because the window is closed more tightly after completion of the ascending pressure difference.
Full scale measurements were made of wind pressures on the 177m high post office tower, London. The variation of pressure with height was studied from recordings made at nine different levels between 49m and 168m above ground level. It is suggested that wind speeds of greater magnitude than those at the top of the tower sometimes occurred at lower levels.
Studies effect of joints between building components on air tightness of buildings, and the factors which influence the air leakage through a joint. As a pilot test, the air leakage for different widths of joints between building components in timber has been studied by varying the pressure between 150 to +/- 700 pa. Describes main apparatus and gives results of the investigation on the leakage of air pressure in various types of joints.
Reports results of studies conducted in Switzerland in small apartment buildings. Air change rates were measured in ten different apartment buildings using N2O as a tracer gas. Measurements were taken for various wind conditions andtemperature differences and with the windows partly open. Finds that ventilation rate increased by a factor of 4 when the windows on one facade were opened by only a few centimetres.
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.
Describes study and operating principles of device allowing a window (or more usually a light-weight cladding unit) to be placed in variable temperature conditions simulating actual summer and winter conditions, in order to determine the airtightness of the window under these conditions. Describes testing of three plastic window frames in the device and supplies the measured values of the airtightness before, during and after the tests, and the corresponding curves.
Login