Sash windows originated in the latter part of the 17th century. At first they featured many small panes of glass held together by wide glazing bars. Within a few decades, improvements in glass allowed slimmer glazing bars and fewer individual panes. Soon the box sash window became the norm for all bar small rural dwellings.
With the advent of plate glass, larger panes allowed larger windows. Homes became lighter and better ventilated. Designs changed. By the middle of the Victorian era, it was common for sashes to have only a single, central glazing
bar or even none at all and horns were added to the sashes to support and strengthen them.
We’re still seeing improvements in glass. That’s one reason why sash windows are still evolving. It’s also because we expect more – we want homes that are warmer, cleaner and safer than those of our predecessors. Using smart materials means we can enjoy the best of both worlds: the grace and elegance of an outstanding and enduring design classic with the comfort, security and energy effciency of a 21st century lifestyle.