English

Studies a sample of 58 occupied homes in Rochester NY to assess 1. the effectiveness of construction techniques designed to reduce air leakage 2. the indoor air quality and air-exchange rates in selected airtight houses and 3. the impact on

Decribes the "collector chamber" method, where a room or whole building is pressurised and the air leaking through the target areas is collected with apressure compensated chamber to a measurement device.

Illustrates some practical aspects of the use of one IR camera and associated equipment discusses some of the problems in interpretation of some pictures representing temperatures of the inside and outside surfaces of buildings particularly problems due to residual effects of the sun on external surfaces, reflection of sunlight into the IR camera, storage of heat from the sun in walls, and cold spots inside a building caused by heat loss by thermal bridges or cold-air infiltration.

Describes the Mobile Infiltration Test Unit (MITU) and its instrumentation, including some preliminary tests of the individual measurement systems. MITU has a completely automated data acquisition system that records air infiltration rates, surface pressures and weather as half hour averages. Theshell of the tracker is well sealed and the quantity ,type and distribution of leakage area is controlled using removable leakage panels in 16 window openings.

Comments on the benefits of tighter house construction and gives a summary of the current tightness levels of the US housing stocks, based on a 300-house survey of infiltration measurements. Looks at 2 case studies of energy-efficient houses both for the details of their construction and for the air quality in the finished houses. Presents a set of drawing details that illustrate specific techniques for reducing infiltration. Includes methods of weatherstripping doors and windows, caulking and sealing, possible leakage points, and installing vapour barriers.

Presents the operating principles for four basic types of air-to-air heat exchangers suited for small scale use: rotary, coil-loop, heat pipe and plate. Discusses individual advantages and disadvantages. Describes test program initiated to evaluate the performance of a few commercial units as well as several units designed and/or built at the University of Alaska. Presents preliminary results from several of these tests along with a critique on theirdesign. Gives a short list of manufacturers of air-to-air heat exchangers in the appendix.

Describes experiments carried out in 4 low energy electrically heated houses incorporating extra thermal insulation and heat recovery mechanical ventilation systems. Airtightness was made an objective so that the ventilation system would provide as much of the required fresh air as possible. Instrumentation was installed during construction to monitor the performance of the houses, with the cooperation of eventual purchasers. The houses were leak tested and sealed where necessary.

Explores the various roles that mathematical models can play in the design of energy efficient ventilation systems. Uses an example (an existing terraced house) to illustrate how models may be used to investigate the energy implications and air distribution patterns of a range of mechanical andnatural ventilation options. Identifies key parameters needed for accurate results, and compares predicted infiltration rates with actual measurements taken in the house. Concludes that models of proven validity are an invaluable aid in ventilation design studies.

Uses the SEGAS "Autovent" constant concentration apparatus to measure the fresh air entering and the local ventilation rate in each cell of amulti-celled dwelling with both natural and mechanical extract ventilation. Measures fresh air entry into each cell using tracer gas constant concentration and decay techniques. Conducts decay tests without artificial mixing, and interprets them by computing the area under the decay curve to obtain local ventilation rates. Compares the 2 measurements, giving the ventilation efficiency of each cell and an idea of air quality in each room of the house.

Gives results from fiel trials of the performance of various mechanical ventilation systems. Carries out measurements in buildings built during the seventies, using the tracer gas decay technique with N2O. Tests 3 cases:< 1. Air supplied only through register above door< 2. Air supplied both through register and the slot under the door< 3. Air supplied only through slot under the door.