Oriel Windows are structural glass installations and therefore have no maximum or minimum scale. However, to ensure that your Oriel window is cost-effective, there are certain constraints that you can bear in mind.6m x 3m is the largest piece of glass made in the UK. If you wish to add single glass panes that are bigger than that into your bay window Oriel frame, they would need to be imported from overseas toughening processors. Obviously, this then contributes considerable costs to the glass construction and lead time. It is for this purpose that most Oriel Window designs will be produced using glass panes under 6m x 3m.