The authors wish to thank: the members of the VCCTL consortium, former and present, for their financial, technical, and moral support for the development of Virtual Testing; J. E. Devaney and her group at NIST for scientific visualization and computer code parallelization; and Geoffrey Frohnsdorff, former Chief of the Building Materials Division at NIST, for his continuing enthusiastic support for the computer modeling efforts embodied in the VCCTL software. This article represents the work of a number of scientists and engineers at NIST and elsewhere.