Towards Standardization of Service Life Prediction of Roofing Membranes
Reference: Lounis, Z., Lacasse, M.A., Vanier, D.J., and Kyle,
B.R., “Towards
Standardization of Service Life Prediction of Roofing Membranes,”
Roofing
Research and Standards Development: 4 th Volume, ASTM STP 1349,
T. J. Wallace and
W. J. Rossiter, Jr., Eds., American Society for Testing and Materials,
1998.
Abstract:
A service life prediction approach for roofing membranes and
systems is
proposed based on a probabilistic modeling of the time-dependent
performance. The
membrane performance is modeled using a discrete Markov chain
that evaluates the
change of performance over time as a result of deterioration or
repair. This stochastic
model will be developed using in-field performance data collected
during roof
inspections, considering the roofing system type, membrane type,
age group, exposure
conditions, and maintenance level. The use of in-field performance
data captures the
interaction between roofing components, as well as the synergism
of the various
degradation factors. The probabilistic modeling accounts for the
uncertainty and
variability of material properties, degradation factors, and quality
of workmanship and
maintenance. The service life is determined considering both the
technical and
economical performances, in addition to the risk of failure; this
constitutes the first step
towards the standardization of service life prediction of roofing
membranes and systems.
Keywords: service life prediction, standards, roofing membrane,
performance,
deterioration, stochastic model, risk of failure, life-cycle cost