Done well they transform a window, however all too often companies fail to appreciate or inform their clients about the impact that internal canes will have on their installation.
Normal “double glazing” companies often provide the cheapest method to mimic glazing patterns, regardless of how real they look.
Cheap to produce, but flat, dull, and extremely poor imitations of the real thing, they remain brilliant white and out of character against the weathered feel of the rest of the window.
We will happily make sash windows with plant on bars, to whatever design pattern you require. We use Georgi® clips to clamp the two bars (external and internal) onto the glass, we then interlock the bars where they cross over to ensure they never become detached. The adhesive backing tape is just there to stop the bars rattling in the wind. The BBA has tested our method of bars and clips and confirmed that they expect them to stay attached for the life of the sealed unit.