The construction industry is currently facing increasing demands to contribute to a more sustainable future, as global challenges such as climate change and the increase in carbon emissions are becoming increasingly critical. Awareness of the environmental impact of the building sector has grown significantly, leading to a heightened interest in circular solutions, resource efficiency, and environmentally friendly material choices. Traditional construction methods are increasingly being questioned, and the industry is shifting towards new approaches where sustainability is a central focus.

This study aims to investigate the potential of replacing conventional stone wool insulation in a wall element with recycled cellulose insulation. The objective is to reduce environmental impact without compromising quality or performance. By comparing the materials in terms of moisture performance, fire classification, energy efficiency, and cost, the study explores whether cellulose can serve as a viable alternative in contemporary building constructions. The research is based on a practically applicable case and relates its findings to current regulations and industry standards, highlighting both the possibilities and challenges involved in the transition toward more sustainable insulation solutions.