Thermal modeling using equivalent circuits in analogy to electrical circuits is a well-established technique, especially in modeling power dissipation in electronic devices and optimizing cooling means. In building construction and facility energy management, these methods still are rarely found: circuit based models are the exception in this field. The inclusion of thermal radiation effects in energy efficiency optimization - especially for insulation structures - is often omitted, although thermography is widely used. Contrary to pure numerical simulations, equivalent circuit methods allow the derivation of useful formulas and rules of thumb. It might be expected that the thermal optimization of buildings in near future will rely on every percentage of potential savings, so the inclusion of thermal radiation into rules of thumb might be a consequence. In the paper we present a short review on such methods. As examples drawn from current research, we discuss applications in facade and roof construction. While the specific problems discussed here are derived from investigations of energy efficiency in building construction, the focus of the paper is on the applied methodology of thermal modeling and its optical aspects. It is understood as a short tutorial paper.