Original windows are a central component of architectural monuments worthy of protection. We therefore want to preserve their testimonial value as true to style as possible or otherwise faithfully reproduce them. Frame, glass, shutter and fittings – what sounds simple is more than the sum of its parts. The craft of historic window construction is an art. When it comes to maintenance and conservation, therefore, only historical techniques and authentic materials such as linseed oil putty as well as authentic, durable woods such as larch, oak and pine come into question.

Since the first documented glassworks in the 13th century B.C., glass as a material in window construction has also undergone constant development: from slug and moon glass panes to blowing, stretching and drawing processes to modern float and vacuum glass. Over the course of time, ever larger windows and glass surfaces became possible thanks to better insulation, filigree glazing bars, profiling and narrow centre sections. Today, modern double glazing or front windows also provide better thermal, sound and burglary protection in historical window construction – without aesthetic compromises.