Energy Engineer, ENER-CORP Energy Systems, Inc., Winnipeg, Manitoba,
Mechanical engineer, UNIES, Ltd., Winnipeg, Manitoba,
Pages: 11 Published: Jan 1986
A field study was carried out to evaluate the effectiveness of air leakage sealing techniques for reducing air infiltration in houses. Presealing and postsealing air leakage tests were performed upon 82 single detached houses. All of the houses were located in Winnipeg or southern Manitoba, a region with an annual degree day value (Celsius) of about 5800. The sample group consisted of 56 conventionally constructed houses of varying size, style, occupancy, and airtightness and 26 nonstandard structures of smaller but identical size and age. This latter group was part of the Flora Place project.
All houses were placed under a negative pressure, and leakage sites were identified using smoke pencils. Windows and doors were weather-stripped and other unintentional openings caulked and sealed using specified materials and techniques.
Based upon the results of the study, the median reduction in airtightness of the conventional structures, defined using the equivalent leakage area at 10 Pa (ELA10), was 31.6% with significant variations occurring both between houses of the same type and between different types of construction. When the houses are examined in groups according to type of construction, it is apparent that the greatest reduction in ELA (36.9%) was achieved in single-story houses. Houses constructed in somewhat more complicated fashion, such as split levels, exhibited less of a reduction. As a group, two-story houses showed the least reduction (24.4%), likely due to the indirect leakage between floors that could not be addressed properly. Within any group, houses with inaccessible air leakage points, such as in finished basement areas, showed the least reduction. The median reduction in the ELA10 for the Flora Place houses was 42.5%, again with significant variations between houses despite their near-identical construction.
Using the air leakage test data and a recently developed correlation model, an estimate was made of the naturally occurring air infiltration rates for all the test houses. This analysis indicated that the sealing produced a median reduction in the infiltration rate of 32.8% for the conventional houses and 46.1% for the Flora Place houses. Due to a lack of equipment, tracer gas tests were not conducted to confirm these values.
Note, however, that the results of this study likely are representative of houses constructed only in Manitoba and possibly in Saskatchewan and Alberta. Since houses in the prairie provinces tend to have low air infiltration rates, the effects of air leakage sealing on houses in other parts of the country could be different from those found in this study.
air leakage, air infiltration, equivalent leakage area at 10 Pa, sealing measures
Paper ID: STP19653S