Minergie is a Swiss quality label for low-energy buildings, focusing on comfort, energy efficiency, and renewable energies. However, a closer examination of the production processes and materials required for certification reveals some limitations. These materials often have significant environmental impacts that are not fully accounted for in the certification process, externalities raising questions about Minergie’s global sustainability. The first phase aims to achieve the Minergie label by meeting its stringent requirements and investigating the environmental harm of the materials used. The project’s second phase presents an alternative approach that rejects the Minergie label’s criteria. Instead, it seeks to achieve similar results, by testing unusual, innovative and sustainable practices. One such practice is using a greenhouse, inspired by examples in Sweden, to envelop the houses. This design maintains comfortable temperatures year-round. Materials will be sourced as locally as possible and reused where feasible. Additionally, the space between the houses will be filled with trees and vegetation, helping cool the air in the greenhouse during summer and reducing the renovation’s carbon footprint. Through this dual approach, the project offers an opportunity to candidly discuss how sustainable eco-labels are, address broader environmental concerns, and seek to meet its design energy efficiency standards and a possible model for truly sustainable architectural renovation.