The composition of these materials, 75% of which come from natural, renewable raw materials, will allow the interior air quality to be improved and make energy savings of 25%. To turn this into reality, a European consortium led by Tecnalia has launched the Osirys project which will create natural, contaminant-free materials for construction purposes. These materials, mainly consisting of natural, renewable raw materials, cut the energy consumption needed to create them, as well as bringing benefits for the buildings themselves. Other advantages of these materials are their weight and durability. As regards weight, the new materials will be lighter than the traditional ones: the plan is to reduce the weight of the façade by over 70%. This would mean savings in transport, but more than anything else, an improvement in the safety of the workers while they carry out the assembly operations. On the other hand, the durability of the ecomaterials will be greater, thus avoiding the need for repairs and work to extend the life of buildings. Ecomaterials neither rot, nor splinter nor run the risk of corrosion as metal structures do. So it is reckoned that the useful life of a 50-year-old building could be extended by a further 10 years. The Osirys project proposes combining six different panels, each one intended for a different function: to improve interior and exterior breathability, to eliminate harmful elements in the air, to improve insulation and to protect against fire, etc. It will be possible to assemble these panels using the "Lego" system and different ones will be included depending on needs. What is more, it will be possible to use this system in new buildings as well as in refurbishments. At the helm of the project is a consortium led by Tecnalia and formed by a total of 18 participants. The main ones are the public company Visesa and other companies in Spain, Finland, Germany, Sweden, the UK, Hungary, the Netherlands, Portugal and Italy. Osirys is a project funded by the European Commission within the 7FP-Framework Programme under the umbrella of “Energy-efficient buildings”. The project is in response to needs raised by the European Commission together with the European Initiative for energy-efficient buildings (EeB) to cut energy consumption and CO2 emissions in the building industry. The project starts this June and will take four years. Before the end of it, three prototypes will be built: in the Kubik building, Tecnalia’s demo building; a real building belonging to Visesa in the Basque Autonomous Community; and a real building in Malmö, Sweden.