On massive envelopes in passively-heated solar buildings: An analytic sensitivity study

An analytic model for the prediction of the effect of massive envelopes on the long-term thermal performance of passively-heated solar buildings is developed. Taking into account radiation heat transfer between the primary (directly illuminated) storage element and the envelope, we derive closed-form analytic expressions for the building solar heating fraction as a function of building and climatic variables. A quantitative assessment is presented for the relative significance of including radiation heat transfer in the analysis and the extent to which massive envelopes can increase solar heating fractions by moderating the storage and release of solar gain.