This paper describes the modelling and simulation work that was carried out to support the design team of the new "Indonesian Jungle" pavilion in Prague Zoo. This pavilion is basically a very large transparent (acrylic) dome maintaining a warm and humid jungle-like indoor environment. Problematic issues include very high solar gains in summer, very high heat losses in winter, and potential condensation against the roof at various times throughout the year. After elaborating the above, the various modelling problems associated with this building are discussed. These include problematic parameter estimation for moisture production and infiltration, and the issue of how to calibrate the generated model. The simulations and results are outlined, and the transformation of these into design information is discussed. The paper finishes by indicating directions for future work in order to be better equipped for addressing design problems such as the one described in this paper.