Climate change is widely recognised as one of the defining challenges of our century, demanding urgent action to mitigate greenhouse gas emissions while adapting to irreversible climatic impacts. Finland stands at the forefront of climate policy, with one of the world’s most ambitious targets: achieving carbon neutrality by 2035, fifteen years ahead of the European Union’s mandate. This target places considerable pressure on the construction sector to transition rapidly toward climate-neutral practices. In this context, the renovation of Finland’s existing building stock presents both a significant opportunity and a set of implementation challenges. This perspective paper explores the potential of bio-clay insulation systems and interior finishing panels, developed from locally available materials, including excavation waste and industrial side streams from agriculture and forestry industry, as a pathway to environmentally sustainable renovations. These solutions offer multiple benefits: they enhance energy efficiency, act as carbon sinks through biogenic carbon storage, and can be tailored to deliver moisture safety and thermal performance under future climate conditions. This makes them potentially suitable for the renovation of concrete sandwich panel apartment blocks, which constitute a significant portion of the Finnish building stock in need of energy-efficient renovation. Moreover, bio-clay solutions hold relevant potential to support indoor hygrometric comfort and occupant well-being by passively regulating indoor humidity and reducing mould risks. This work outlines the scientific and practical potential of implementing such materials at scale, and their role in enabling climate-resilient, sustainable, and health-oriented renovations of Finnish concrete panel apartment blocks, in the face of climate change.