Un percorso metodologico verso edifici zero-carbon

The ambitious and cost-effective path for achieving climate neutrality in construction by 2050 re- quires from one side a large reduction of the energy demand for building operation as well as a large share of renewable resources, and from the other side a massive substitution of carbon intensive materials with a widespread implementation of carbon negative solutions. In this paper, a parametric framework for Life Cycle Zero-Carbon Building (LC-ZCB) was developed to mini- mize both the operational carbon (OC) and the embodied carbon (EC) to achieve the absolute- zero target. A wide set of the most influencing parameters during the early-stage design was im- plemented in Grasshopper and tested on a prototype residential building. Two alternative options were considered for the design of the envelope: the conventional base option (OPT), based on the use of a timber frame and conventional mineral insulation, and a bio-based solution (BIO), which adopts hemp shives and hemp fibers as thermal insulation. From the 200 combinations generated within the parametric framework, nine OPT and six BIO combinations which most minimized the whole life cycle carbon emissions were selected. From the results achieved, none of the OPT combinations were able to reach the absolute-zero, due to the carbon intensity of the construction materials and the limited carbon uptake provided by timber products. Contrarily, all BIO solu- tions were able to achieve a nearly LC-ZCB carbon goal, due to slightly negative EC of biobased insulation and the fast carbon uptake during the regeneration crops.