Author: Craig Devine and Richard Flint
ISBN No: 9 781848 063051
Review date: 04/05/2024
No of pages: 40
Publisher: BRE
Publisher URL:
http://www.brebookshop.com/details.jsp?id=327136
Year of publication: 08/07/2013
Brief:
Security glazing: is it all that it’s cracked up to be? A guide to the selection of effective security glazing
A guide to the selection of effective security glazing at 40 pages may not count as a book, but it’s got a neat title, Mark Rowe writes.
Security glazing: is it all that it’s cracked up to be? So ask Craig Devine and Richard Flint. It’s from the BRE, the Watford-based building product testers. The work arose from burglaries in the West End of London – smash and grab thefts of jewellery or expensive clothes or bags from shop windows. In other words, windows offer least resistance – less than doors and walls – to the thief, maybe arriving and leaving at speed on a moped, who take something heavy and sharp to a window. Or, think of the August 2011 riots. But how to know what glazing product is right for your shop or high street office – will a window that can resist a hammer offer good protection if a bomb goes off nearby? Or a bullet – more a factor for an armoured vehicle or a cash office. Hence the BRE Trust-funded research. As the authors begin, it’s worth recalling that we have used glass for millennia to let light in. But, burglars may seek to break glass, or attack window frames that causes glass to break. As the guide hints, what is the good of ever more resilient doors, if the glass is not as resistant? It then takes us through the types of glazing – such as fire-resistant (think of how some rioters set out to burn the properties they looted), glass bricks or laminated glass. Did you know the most common form is glass is ‘float glass’, a centimetre thick that does tend to break into jagged shards, and so best not used in (and indeed not allowed) fire exits, schools and the like. As for wired glass – glass with steel wire mesh in – you may think it’s stronger, but the wires actually weaken the glass: “However, when the glass is broken the wire mesh helps to retain the shards for safety.” This guide is aimed at specifiers. It’s a ‘delicate balance’, the authors write: between protecting a place, cost, what it looks like, and meeting building regulations. You might not find something that does all you want (assuming the architect and blast engineer can agree) at the ‘right’ price. Tests on the same specimen of glass to different (British and other) standards ‘can give an alarming spread of results’, and it won’t do just to specify thicker glass, the authors warn. Other points the guide covers include noise (do you want glass to let noise in, on a busy road?) You may want to skip straight to the conclusions which include: “… glazing incorporating layers of polycarbonate offered the greatest resistance to manual attack, and that specifying glazing by thickness alone was not sufficient to provide adequate levels of resistance.” Likewise you might want to skip to the ‘specification sequence’ to help you assess what glass you need for a location and the threats to it. Also useful at the very end are the glazing standards listed, and what we know about attacks on glass from the government’s British crime survey. If you want a clear look at glass, you need this document.
