Renovation of existing buildings is proposed as a solution for buildings that do not fit the Climate Target Plan 2030. In the Netherlands, there is a new mandate requiring Dutch office buildings to attain a minimum EPC class C rating by January 1st, 2023. Recent studies indicate that 10% of Dutch office buildings are currently rated at EPC class D or lower, while numerous existing office buildings have yet to obtain an EPC rating. This situation necessitates a surge in renovation projects in the near future. However, a complex relationship exists between energy-efficient measures and Indoor Environmental Quality (IEQ) post-renovation. Healthy buildings, characterised by adequate IEQ, contribute to heightened overall satisfaction and productivity among their occupants. This research is centred on crafting an advisory report aimed at guiding the decision-making process preceding office renovations for owners of Dutch owner-occupied offices. The following main research question relates to the goal of this research: “How can the renovation decision-making process, prior to renovation, of private owners of Dutch owner-occupied office buildings be guided with a focus on improving energy efficiency and Indoor Environmental Quality?”. The objective is to surpass the EPC class C requirements while concurrently prioritising IEQ enhancements to boost employee satisfaction and productivity. To achieve this, several case studies were conducted through in-depth interviews with stakeholders involved in the renovation projects. This approach sought to gain insights into the decision-making processes of office owners prior to the execution of renovation practices. The findings of this research hold significance for those initiating future office renovation projects, project managers, and public authorities seeking strategies to accelerate the rate of energy-efficient and healthy office renovations. The study’s outcomes indicate that the decision-making process preceding office renovations can indeed be steered towards achieving both energy efficiency and improved IEQ. This can be accomplished through a comprehensive and cooperative approach that emphasises awareness, education, regulation, and financial security.