Reduction of embodied emissions is crucial for achieving sustainable and low-carbon building practices. GreeNest creates an ecosystem that integrates CO2 neutral building materials (reused, recycled and locally sourced biogenic materials) and renewable energy sources (abiotic components) into the building design, together with human response and natural/green systems (biotic components) to demonstrate resource efficient construction that needs less materials and implements energy-efficient circular construction practices. The project targets 100% carbon free construction through the application of biogenic materials that store carbon, the reduction of embodied emissions by 50% with respect to NZEB standard, ZEB or even positive energy standards via renewable energy sources with remaining primary energy consumption less than 30-40 kWh/m2, reduction of GHG emissions by 60% and increased productivity of construction by >30%. GreeNest delivers a palette of innovative solutions for new buildings, addressing all stages of the building’s life, from the design stage up to the end of the building’s lifetime and disposal stages (including re-use and recycling of components). It proposes sustainable envelope components based on low carbon and carbon-neutral market mature materials, using on-site renewable energy, reducing waste, enhancing productivity of construction through digitization and demonstrating circular economy principles. The innovative solutions will be fully demonstrated in four real and two virtual new construction projects in five countries using local and regional value chains increasing the potential for replication across Europe. The GreeNest consortium benefits from a strong industrial and commercial involvement with 11 SMEs 1 Large Company 3 Universities, 3 Associations and 2 Public bodies from 8 European countries.