The Energy Saving Ordinance (EnEV) aims to further reduce CO2 emissions in both new construction and renovation areas. It also sets requirements for half-timbered walls, which can sometimes contradict the need for compatible restoration of existing structures. An unconsidered application of the ordinance to half-timbered buildings can lead to serious renovation errors. This second revised edition of the guide provides the reader with an overview of the tightened requirements of the current EnEV 2009 and outlines the possibilities and limitations of implementing this regulation. The reader is guided on how to find an individual solution for proper restoration and maintenance of half-timbered structures. The authors examine all aspects of energy-efficient building renovation, from construction techniques to building physics properties.