<p>Athens is struggling with intensifying climate and social pressures: urban heat island, water scarcity, and lack of public green space coupled with socio-economic pressures. These citywide challenges are magnified at the building scale in the <i>polykatoikia</i>, the dominant Athenian residential typology. Most polykatoikies are aging, poorly insulated, and governed through fragmented multi-ownership structures, creating decision inertia that obstructs even basic climate action.Superblocks, first introduced in Barcelona, are effective in reclaiming streets from cars and improving public space. Yet, current approaches largely overlook the building stock itself, missing an opportunity for buildings to actively support climate adaptation and social cohesion within the superblock. In Athens, this omission is critical: transforming the city requires focusing on the polykatoikia. Hence, this study adapts the superblock model to Kypseli, Athens’ densest neighborhood, as a means to tackle these challenges by shifting the intervention focus to the polykatoikia scale. Three research questions guide the work: (1) How can polykatoikies become climate-resilient and socially cohesive? (2) How can building-scale interventions reinforce street- and neighborhood-scale strategies? (3) What participatory mechanisms can overcome ownership fragmentation? Using a mixed-methods approach; GIS and drone mapping, street-level audits (EpiCollect), a resident survey (<i>N</i> = 98), and expert interviews, the research analyzes polykatoikies through a <i>Skin–Veins–Soul</i> lens. Based on this diagnosis, it introduces Demokatoikia, a five-pillar framework: Green (living skin/biodiversity), Blue (rain/greywater reuse), Yellow (energy retrofits), Orange (universal accessibility), and Red (Commons/cultural activation). Inspired by Greece’s NGO <i>Rock the Block</i>, it embeds co-design and citizen stewardship to break decision inertia.</p>