Resumen
The world is on the eve of major changes in the way energy and material are used, and the building and construction sector is at the forefront. One of the revolutionary changes is that for 0-energy houses and buildings. Many countries already have some projects established, and legislation is following, first requiring near 0-energy, but undoubtedly this will evolve into 0-energy as basic requirement. Buildings will generate all required energy from within their building lot, from incoming free and renewable energy sources: solar radiation and earth core heat mainly. In other words, there are no polluting or depleting issues anymore related to energy consumed to operate a building. This will change the whole approach in evaluation and optimization of the environmental performance of buildings: while the energy-driven measures for buildings become obsolete, it will be materials needed for this transition that have to become the main focus, as argued in this paper.