Reducing energy consumption of residential and commercial buildings is a major challenge nowadays. One of the strategies to achieve a significant reduction lies on building renovation. On this regard, a project targeting the industrialization of high performance thermal renovation for apartment buildings is been executed. The renovation is based on an external envelop composed by rectangular wood-made panels that cover the whole building. Two concurrent configuration tasks within the project have been identified: The configuration of each one of the panels w.r.t. to the facade and the configuration of the entire facade using a set of these panels. We focus our efforts on the development of a decision support system for the configuration of panels and facades. In this paper we introduce Calpinator, a Java-based configuration tool which is the heart of the decision support system for the project. The tool uses the notion of Constraint Satisfaction Problems as underlying model and implements a smart greedy-recursive algorithm to find a feasible configuration. In this communication we present the tool’s design, its features and its implemented algorithm. We use a real-world scenario to illustrate the kind of facades the system can deal with.