Describes the first stage of a project to study domestic background leakage. Fundamental flow measurements have verified the crack flow equation for the simplest crack type for a much larger range of crack and flow parameters than have previously been examined. It is hoped to develop a portable, automated pressurization system capable of identifying and quantifying background leakage areas in rooms.
Smoke control makes use of mechanical fans to produce airflows and pressure differences to control smoke movement. Describes one day of tests of the smoke control systems at the 6-storey VA hospital, San Diego, California.
Contains articles on rain penetration and moisture damage in residential construction, moisture sources in houses, control of surface and concealed condensation, and ventilation of houses. Illustrates the various types of condensation problems that may occur, explains the active processes involved in some of these problems and discusses in detail the principal factors surrounding these phenomena i.e. sources of moisture, choice of construction detail, and current ventilation practice.
The multiple tracer gas technique developed at UMIST has been applied to the measurement of roof-space ventilation rates and house to roof-space air movement, for various types and combinations of roof-space ventilation. It has been shown that ridge tile ventilators, whilst increasing roofspace ventilation rates at low wind speeds, also significantly increase house to roof-space airflows over the whole range of wind speeds. This has implications not only in terms of energy wastage, but, more significantly , in terms of increased moisture rates to the roof-space.
Reduction in air leakage rates due to weatherization of homes can be determined by fan pressurization and tracer gas techniques, but only the latter gives the results under normal occupancy conditions. Assessment of such rates measured before and after weatherization must consider their dependence on wind speeds and inside-outside temperature differences.
The theoretical background, admittance measurements and experimental work on interstitial condensation in lightweight roofs caused by air leakages is discussed. Describes a theoretical model of condensation behaviour taking into account moisture transfer by air flow as well as diffusion. Gives the air flow admittance for various roofing materials, ceiling systems and different roof-sections. Experimental results agreed well with the theoretical model.
Facts and ideas are presented to improve cost effective designs for airtightness and ventilation systems. Schematically alternative measures to save energy are presented. An investigation of the rate of ventilation in 25occupied houses is described, using pressurization, tracer gas and measurements of air flow through exhaust air terminal devices. At a mechanical ventilation rate of 0.25 ach, the measured total ventilation rate averaged 0.29 ach (minimum 0.12 and maximum 0.50). Further results are given for 5 more recently constructed houses.
Uses air leakage measurements in laboratory and site studies in Poland to define a power law relationship between pressure acting across the opening and flow rate, and explains the effects on heat loss calculations. Results of indoor climate measurements over a two year period are given. Describes use of a computer model to calculate heat demand of different ventilation systems. Real heat requirement is about 40% larger than the calculated values.
This report focuses on the repair and upgrading of existing windows to acceptable levels of air and thermal resistance. Improvements to existing windows can be effectively achieved for as low as 25 to 50 cents per square foot by caulking and weatherstripping the primary window and then installing an inexpensive interior storm window. 27 interior storm window products are examined and details of design, operation and performance are given. Air infiltration test results are also examined and the thermal performance of each window system in terms of whole house energy savings is evaluated.
Reviews literature on indoor air quality in housing, nature of contaminants and their sources, health effects, standards and guidelines, impact of air sealing on indoor air quality, sources of uncontrolled air leakage, airtightness and natural ventilation, airtightness of new and existing housing stock, air change in new and existing housing, impact of air sealing on airtightness and ventilation, indoor air quality in tight houses, impact of occupant behaviour on ventilation, measures to improve indoor air quality, identifying problem houses, indoor pollution control strategies, and ventila
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