HTB2: A flexible model for dynamic building simulation

The model described is characterised by a highly modular structure in which different processes are clearly separated so allowing the addition and substitution of alternative algorithms to be readily made. It is written in ANSI standard Fortran 77, has been successfully compiled and run on machines ranging from an IBM XT to a DEC VAX with only minor changes and is supported by comprehensive documentation. The paper outlines the concept on which the model is based, the main features of its implementation and the facilities it provides.