Why are architects obsessed with ever thinner window frames? Aluminium profiles have shrunk from 105 mm to a stunning 15 mm. More glass means brighter rooms, wider views, smaller energy bills. So, how slim can an aluminum window safely go? This post reveals the limits, benefits, and design tips. Defining "slim" in aluminium windows is key. With profiles shrinking from 105 mm to just 15 mm, architects are embracing the trend for its modern aesthetic and functional advantages. In this post, we’ll dive into the engineering behind ultra-slim windows, the materials that make them strong, and how they provide increased natural light, improved insulation, and better energy efficiency—all without sacrificing durability or safety.