Loads? What loads?
When specifying glass partitions, you ask yourself the following questions:
- Does the system meet a chosen acoustic performance?
- Does the system meet a chosen fire performance?
- Does the system meet a chosen structural performance?
Questions 1 and 2 can be demonstrated by test/assessment data or certification, but what happens when question 3 is unclear?
Confusion still exists in modern day specification for frameless glass screens or partitions. The easy bit to understand is that when the screen protects a change in floor level, the requirements are unequivocal;
Under BS6180, the glass is not allowed to deflect more than 25mm laterally, relevant to its fixings.
This can be calculated to be compliant by choosing the right glass thickness when resisting a specific line load.
This will either be 0.36KN/M (residential), 0.74KN/M (typically offices), 1.5KN/M (typically retail) and 3.0KN/M (typically high crowd areas and stadia etc.)
Every contractor should be providing a calculation and specification for the purposes of Building Control authorisation.
But what about standard glass partitions?
Here, the rules and interpretations are less clear. In the ‘old days’ the mantra was always to be compliant with BS5234, but there is growing evidence that suggests this is not a relevant standard for glass which, as a building material, will deflect many times its own thickness under load without suffering any ill effects.
Here at Planet we take the view that the use of this ‘material’ needs justification against the ‘requirement’. This can be an assessment of the use ‘category’; compliance with CDM; and, quite often, the overlooked requirement of internal air pressures and how the glass performs when that happens.
Some things to think about before choosing; a manufacturer, a partitioning contractor, or the glass processor. Thankfully, Planet are all of these. Get in touch with us to discuss your partitioning needs in more depth.
Written by Neil Paddock – Associate Director, Planet Architectural Glass