Snow loads on multi-level flat roofs in Canada

TitleSnow loads on multi-level flat roofs in Canada
Publication TypeConference Proceedings
Year of Conference1987
AuthorsTaylor, D. A.
Conference Name55th Annual Western Snow Conference
Series TitleProceedings of the 55th Annual Western Snow Conference
Date PublishedApril 1987
PublisherWestern Snow Conference
Conference LocationVancouver, British Columbia
KeywordsBuilding codes, Flat roofs, Multi-level roofs, Snow density, Snow drifts, Snow loads, Snow variability

Between 1967 and 1982, snow depths and densities were recorded on 44 single- and multi-level flat-roofed buildings between Halifax and Edmonton. Analysis of the data indicates that the specific gravity of snow on roofs is about 0.3 and is on the average, about 18% higher than that recommended for design In the 1985 National Building Code of Canada (NBC). The paper presents maximum average and maximum roof snow loads on upper and lower roofs (outside the drifts) and compares these to values recommended for design in the NBC. Data on maximum snow loads in the drifts is compared to NBC provisions. The statistical variability of the snow loads is analyzed to aid establishment of load factors for Limit States Design in the Canadian Code.