Residential energy consumption remains a significant driver of CO2 emissions in European buildings, demanding urgent action in the face of the climate crisis. While prevailing efforts have predominantly concentrated on enhancing energy efficiency and integrating renewable sources, addressing the climate urgency and resource constraints necessitates a paradigm shift towards sufficiency principles. Swedish statistics on Single-Family Houses (SFH) show that more than a third of households inhabit oversized spaces in aging buildings needing renovation. Sufficiency-oriented renovation strategies—optimizing, or reducing living areas per capita— present a promising avenue to achieve substantial energy reductions. This approach also opens the potential for space rentals, yielding combined energy and space efficiency advantages. In addition, the literature highlights reduced maintenance costs and potential urban housing crisis mitigation. However, practical implementation faces multiple obstacles.This paper investigates SFH owners' attitudes towards space-sufficiency interventions, focusing on living size preferences and identifying barriers and opportunities for sustainable housing. Through focus group sessions with SFH owners in November-December 2022, qualitative content analysis revealed that reducing living space per capita faces multifaceted challenges, despite potential benefits.These challenges encompass not only personal and psychological considerations but extend to economic, infrastructural, and policy barriers, including issues such as the potential breach of privacy, disruptions due to noise, dilemmas related to ownership and independency, disruptions to work-life dynamics, inadequate familiarity with sufficiency principles, and uncertainty imposed by space constraints. Strategic integration of sufficiency principles into energy-renovation policy alternatives necessitates a holistic approach that addresses these barriers, and some form of incentives may be needed to catalyze the adoption of sufficiency principles effectively.