Sustainable building is decisively developed by building physical qualities. Around half of the evaluation criteria have - directly or indirectly – issues such as energy efficiency, economic structural thermal protection, thermal comfort, sound insulation, room acoustics and daylight quality. The demand for durability, maintenance, freedom from hazardous substances and unproblematic disposal require extensive knowledge of building materials, building methods and building techniques, especially with regard to seals, coatings, coverings and corrosion protection methods. With our core competence as consulting engineers for building physics we are part of the planning team. Wide experience has been gained from building physical measurements and quality assurance in the course of technical supervision during constructions as well as from judicial and extra-judicial activities. This enables the execution of cost-conscious planning precisely adjusted to the client´s needs. Our practical experience acquired in more than 30 years has been completed by knowledge gained from own research studies and from cooperation with universities. Our findings have also influenced the development of new building materials, new components and construction methods.