Roof Loads for Reliability Analysis of Lumber Properties Data


  • Michael B. Thurmond
  • Frank E. Woeste
  • David W. Green


Roof loads, reliability, lumber, strength behavior, adjustment factors


With load information reported in previous studies, distributions of maximum lifetime roof loads are developed in a form suitable for use in reliability analyses of lumber properties data. A lognormal distribution is chosen as best representing normalized maximum lifetime roof snow load.

Examples are given in which contrasting lumber data sets are compared using the calculated load distributions and assuming that each set must provide equal reliability (equal safety) in the final design. A factor, k, resulting from this reliability analysis is shown to be a logical adjustment parameter for use in engineering design codes.


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Research Contributions