Briefly reviews ventilation requirements, types of ventilation , driving mechanisms for natural ventilation and infiltration, natural ventilation, infiltration and air leakage, air leakage sources, empirical models and infiltration measurement.
Measurements have been made of infiltration rates and air leakage characteristics of the building envelope in 38 dwellings all built within the last 20 years and covering a range of construction types. Conventional tracer gas techniques were used (employing nitrous oxide as the tracer) to determine air infiltration rates. Overall leakage characteristics were measured under pressurization using a fan. Some correlation was found between the overall leakage characteristic and the actual infiltration performance of a dwelling.
As part of a study by the Building Research Foundation on control methods for the thermal quality of homes, research has been carried out into the usefulness and consequences of a measuring method for the determination of the the airtightness of houses. Airtightness measurements were carried out in sixhouses. Data on occurring ventilation was already available from other research. It appears that the pressurization test for the airtightness of houses can be used to determine the thermal quality of the home.
The first part of the study describes thermography generally as a method for non-destructive testing of a building envelope for thermal and air tightness properties. The study has resulted in a two stage testing method of which pressurizing is an essential part. The field study has shown that thetwo-stage method is suitable in detection of air leakages, showing that the major part of thermal defects in the building envelope are due to air leakages.
Reports pressure tests of the air leakage of an apartment building. The building is three storeys with a cellar above ground. There is a mechanical exhaust system and in addition every apartment has a kitchen fan.Pressure tests were made in each apartment. Leakage points were located with smoke tests. The leakage of windows and doors was determined with the "plenum" method. Each window was surrounded by a "plenum" and leakage at the boundary between plenum and wall was eliminated by an auxiliary fan which maintains the same pressure in the room as in the "plenum".
This practice represents a standardized technique for measuring air leakage rates through a building envelope under controlled pressurization or evacuation, and is applicable to small temperature differentials and low-wind pressure conditions. It is primarily intended for use in one- story buildings.
Reports investigation of the limiting conditions that produce frosting on air-to-air heat exchangers. Also determines the adequacy of provisions for the prevention of frosting and ice buildup. Four types of heat exchanger were investigated as part of a more general investigation of the operating characteristics of air-to-air heat exchangers. Also reports investigation for various types of energy recovery systems of the cross leakage or contamination of the fresh air by the exhaust air.
Comments on the aesthetic aspects of window renovation and replacement and describes common forms of deterioration giving detailed suggestions for repair and for the improvement of air tightness and sound insulation.
Discusses standards and testing procedures for window air and water tightness. Describes apparatus used at the Technical Centre for Wood. Gives brief results of airtightness tests on 70 windows of different types subjected to a pressure of 10mm of water and of water tightness tests on 40 windows. Describes a test wall, designed to enable "hurricane" tests to be made. Appendices giveinformation on precipitation in France and discuss water-proofing products.
An energy saving survey was carried out in an office building in Stockholm during the autumn of 1978. The measures which were proposed are now being carried out. This report details the measurements made which include, airtightness testing of the building, pressure drops across facades, air flow measurements, temperature measurements in ventilation systems, temperature measurements in rooms, boiler combustion efficiencies, electricity consumption, oil consumption and thermographic inspection.
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