The reverse butt joint is something unique to Stellar and is one of the features that makes it so special.
When making windows that contain opening and fixed panes, the normal process is to reverse part of the frame. This is simple with PVC-U which can be welded back together, but in aluminium windows, the joints are created in a different way.
Most aluminium systems compromise and use dummy sashes, couplers or reverse rebate adaptors to ensure their windows can be internally glazed. Unfortunately, this detracts from the appearance of windows and uses more resources.
The Reverse Butt Joint from Stellar is unique. It’s a patent-pending design which solves the problem, allowing internally glazed windows without the extra, chunky sashes. The window’s wonderful slim lines are preserved, and more daylight can enter your home.