Snow Friction Coefficient for Commercial Roofing Materials
Publication: Journal of Cold Regions Engineering
Volume 32, Issue 1
Abstract
Redistribution of snow loads on two adjacent buildings of different heights is addressed. The term slippery roofs is used but it is not defined. Measurements of friction between snow and commercial roofing materials are carried out to help specify the term. In order to determine a static coefficient of friction, the Coulomb friction principle of measuring inclination increase until specimen movement begins is applied. A test apparatus is designed and produced. Single-ply roofing materials such as membranes made of polyvinyl chloride (PVC), thermoplastic polyolefin (TPO), ethylene propylene diene monomer (EPDM), and modified bitumen (MB), as well as painted industrial metal profile specimens are tested. Snow specimens from fresh snow are prepared and tests are carried out under laboratory conditions. For the given conditions, although deviating from full-scale realistic conditions, snow samples slid at different angles depending on the roofing material type. Average values of sliding angle for PVC, TPO, EPDM, and MB membranes and metal sheet are determined to be 6°, 15°, 20°, 57°, and 22°, respectively. Based on the published provisions and given test conditions, commercial roofing materials can be categorized as slippery.
Get full access to this article
View all available purchase options and get full access to this article.
References
ASCE. (2013). “Minimum design loads for buildings and other structures.” ASCE/SEI 7, Reston, VA.
ASTM. (2013). “Standard guide for measuring and reporting friction coefficients.” ASTM G115, West Conshohoken, PA.
Casassa, G., Narita, H., and Maeno, N. (1989). “Measurements of friction coefficients of snow blocks.” Ann. Glaciol., 13, 40–44.
Isyumov, N., and Mikitiuk, M. (2008). “Sliding snow and ice from sloped building surfaces: Its prediction, potential hazards and mitigation.” Proc., Int. Snow Engineering Conf. VI, Whistler, BC, Canada.
Jelle, B. P. (2013). “The challenge of removing snow downfall on photovoltaic solar cell roofs in order to maximize solar energy efficiency—Research opportunities for the future.” Energy Build., 67, 334–351.
Kurahashi, I., Honda, A., Tomabechi, T., and Fukihara, M. (2000). “Estimation of snow load on a large-scale inclined roof of Tajima Dome.” Snow engineering, recent advances and developments, A.A. Balkema, Rotterdam, Netherlands, 195–199.
Lovlin, T., Hochstenbach, F., and Weachter, B. (2008). “Snow loads and roof insulation—A building code disconnect.” Proc., 6th Int. Snow Eng. Conf., Whistler, BC, Canada.
Lutes, D. A. (1970). “Snow loads for the design of roofs in Canada.” Proc., Western Snow Conf., Victoria, BC, Canada, 61–67.
MacKinlay, I., Flood, R., and Heidrich, A. (2000). “Roof design in regions of snow and cold.” Snow engineering, recent advances and developments, A.A. Balkema, Rotterdam, Netherlands, 213–224.
Memorandum. (2015). “Work plan approval—Determination of coefficient of friction for slippery roofs.” National Research Council Canada, Ottawa.
NBCC (National Building Code of Canada 2015). (2015). “Canadian commission on building and fire codes.” National Research Council Canada, Ottawa.
Paine, J., and Bruch, L. (1986). “Avalanches of snow from roofs of buildings.” Int. Snow Science Workshop, Lake Tahoe, CA.
Sakurai, S., Abe, O., and Joh, O. (2004). “Wind tunnel investigation of snow accumulations on a single flat roof and a two-level flat roof using artificial snow.” Proc., Int. Snow Engineering Conf. V, CRC Press/Taylor & Francis Group, Boca Raton, FL, 177–184.
Sida, M. (2015). “Contribution to the snow protection solutions for pitched roofs.” Dissertation thesis, Slovak Univ. of Technology in Bratislava, Bratislava, Slovakia.
SINTEF. (2008). “SINTEF Method 169—Measurement of friction between snow and roofing. Method A—Fricton coefficient determination between snow and roofing by horizontal plane applied pulling force method. Method B—Fricton coefficient determination between snow and roofing by inclined plane slip method.”, Trondheim, Norway.
Taylor, D. A. (1983). Sliding snow on sloping roofs, Canadian Building Digest, National Research Council Canada, Ottawa.
Tsuchiya, M., Hongo, T., Tomabechi, T., and Ueda, H. (2000). “Wind effects on snow accumulation on two-level flat roofs.” Snow engineering, recent advances and developments, A.A. Balkema, Rotterdam, Netherlands, 323–328.
Williams, C. J., Carter, M., Hochstenbach, F., and Lovlin, T. (2004). “Sliding snow and ice on buildings: A balance of risk, cost and aesthetics.” Proc., Int. Snow Engineering Conf., Vol. 26, CRC Press/Taylor & Francis Group, Boca Raton, FL, 59–64.
Xuanyi, Z., Yunquing, Z., Ming, G., and Jialiang, L. (2013). “Simulation method of sliding snow load on roofs and its application in some representative regions of China.” Nat. Hazard, 67(2), 295–320.
Information & Authors
Information
Published In
Journal of Cold Regions Engineering
Volume 32 • Issue 1 • March 2018
Copyright
©2017 American Society of Civil Engineers.
History
Received: Aug 30, 2016
Accepted: May 19, 2017
Published online: Aug 30, 2017
Discussion open until: Jan 30, 2018
Published in print: Mar 1, 2018
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.