At the dawn of the Patent Glazing era, a consistent production of glass had evolved at a dependable width and glazing bar centres have historically remained at this width since (approximately 600mm centres or 2 foot)
Conveniently, a 600mm wide pane of glass or double glazed unit can be carried safely and practically by two site personnel under each man’s arm, and this rule of thumb for the optimum width remains today.
Wider centres than 600mm can be used on Patent Glazing, but consideration must be given to the logistics of access, provision of lifting equipment and future repairs/replacement.
Under CDM the Designer has a responsibility to specify suitable products to enable a project to be executed safely. It is therefore important that the Patent Glazing Contractor is approached early on in the design stage to discuss the practicalities of using glazing panels with large widths.
We do not recommend the use of 6.4mm laminated glass in sloping patent glazing at centres over 650mm, due to the risk of mechanical breakage occurring (self weight).
At wider centres, we recommend using toughened glass or a special toughened laminated composition