Sometimes, the best way to explain advanced physics is with a bit of melted chocolate.
At first glance, PassivGlas™ looks like any ordinary window. Transparent, solid, perfectly normal. But hidden inside is something that completely changes how heat behaves. Two sheets of glass, welded together, with a pure vacuum in between.
No air, no gas, nothing for heat to travel through.
And that’s where the magic happens.
In most materials, heat always finds a way through. It passes from molecule to molecule, flowing like a quiet current. But in a vacuum, there’s nowhere for it to go. So when one side of PassivGlas™ is heated to over 200°C, the other side stays cool to the touch.
That’s not theory. That’s physics you can feel.
To show it, we ran what we now call The Chocolate Test. A piece of chocolate placed on the heated side melts instantly, turning glossy and soft within seconds. Yet the opposite surface stays so cool you could hold it in your hand. That’s the difference vacuum glazing makes.
This same principle, scaled up, transforms how buildings hold warmth. PassivGlas achieves U-values as low as 0.44 W/m²K, locking in comfort while keeping energy use down. It also blocks up to Rw 41dB of noise, so the world outside can stay exactly where it belongs.
And it does all that in a form as slim as 6.15mm, toughened as standard, and ready for heritage restorations, retrofits, or modern builds alike.
It’s glass engineered to make homes warmer, quieter, and far more efficient for decades. Built to last 25+ years, backed by a 15-year guarantee, and support from our head office in the North West of England.
The Chocolate Test might look playful, but the science behind it is anything but. It’s a glimpse of how small innovations can change the way we live. Not with complex systems, but with simple, elegant design.
👉 PassivGlas™. The science of comfort, beautifully clear.