This paper describes the calibration and validation of a combustion cogeneration model for whole-building simulation. As part of IEA Annex 42, we proposed a combustion cogeneration model for studying residentialscale cogeneration systems based on both Stirling and internal combustion engines. We implemented this model independently in the EnergyPlus, ESP-r and TRNSYS building simulation programs, and undertook a comprehensive effort to validate the model's predictions. Using established comparative testing and empirical validation principles, we vetted the model's theoretical basis and its software implementations. The results demonstrate acceptable-to-excellent agreement, and suggest the calibrated model can be used with confidence