Safety Glass – Laminated and Toughened

Gerry Whelan talks about the two major types of Grade A Safety Glass - toughened and laminated. He discussed the differences of the two, why it is needed, which type is used in particular places and how to spot if a glass installed in your house or office is a safety glass or just an ordinary glass.

Wayne: Today my guest is Gerry Whelan who joins us from Brisbane in Australia where he’s the CEO of Archer Glass, a Mount Gravatt based firm that deals with architectural glass. Gerry welcome to the program.

Gerry: Good morning Wayne. Thank you.

W: Now Gerry, today I’d like to turn to safety glass because it is a very critical part of putting glazing into your home. Can you define what safety is for us?

G: We have Grade A safety glass and Grade B safety glass. Grade A safety glass is toughened glass or laminated glass, they’re both Grade A. And then the Grade B safety glass of course is the old fashioned wired glass with a mesh running thru it.

W: Now that glass with the mesh running thru it is kind of industrial in its look and I guess in its application. Let’s talk about the first few types of glass you mentioned, laminated and toughened. What’s the difference between them?

G: With the laminated - if it breaks or when it breaks - there’s a lamination in the center which controls the whole thing together and it doesn’t just crash down in pieces. Whereas that toughened when it’s broken just shatters into pieces and falls down.

W: I see. So that lamination, I’ve seen broken glass that looks like it’s got a bit of plastic wrapping between two layers of glass. That’s what you’re talking about?

G: That’s it, yes.

W:  So Gerry in terms of which one do I use, what should guide me about whether l want laminated glass or toughened glass in my house?

G: Toughened glass, you might use on a bench type in the kitchen because you’re gonna put a hot pot on there from the oven maybe so it stands up to heat or a splashback in the kitchen behind the stove where all the cooking and steam will get it quite hot and then it won’t shatter. Whereas if you use laminated glass in those situations, it would just crack with the heat. With the laminated if you put a solar film on it in direct sunlight, the heat build-up can crack it too so you would also use toughened in that situation. Laminated then you would use in other areas like in your patio door or something where if it’s to break, your building is still secure because the laminated glass holds together.

W: Is there a difference in price Gerry?

G: Pretty much they come up to about the same price. There’s minimal difference between them.

W: And what about workability? Are they different to work with?

G: Absolutely. With laminated we can cut it from stocks, same day and install it. With toughened it has to go thru a process where it’s cut first and then put thru like an oven type process where it’s brought up to a very high temperature and cooled down quickly which causes the toughening to happen and this is usually 3 to 5 days lead time then from the day in order so it delays the job.

W:  Ah I see. Now Gerry you mentioned cutting laminated glass, I’ve seen glaziers do it and I’ve always been impressed with the skill. They kind of score the glass and put a bit of pressure on it, and when they do it always breaks beautifully along the line. How does the lamination affect that?

G: When you cut laminated glass, it’s two pieces of glass separately laminated together so you have to cut both sides directly opposite with the cuts opposite each other. So you can cut one side, score one side and crack open the cut, turn the panel of glass over when cut the opposite side and do the same thing. And then you bend it down and cut or burn the interlayer like by melting it or by cutting it with a blade to separate the interlayer which is quite strong.

W: See, one of the reasons why tradesmen are called tradesmen is because they know the tricks of the trade and clearly I should leave cutting my laminated glass to a professional.

G: Yeah, it’s kind of a practice thing like a lot of things with trade. Like a knack, the old word ‘knack’ but simply practicing from doing it, it just comes naturally whereas as someone maybe doing it once off from the first well they just haven’t got that flow perhaps to do it.

W: Yes. I can imagine many apprentices who have wept a little bit at the first time they’ve tried that.

G: Yeah, you get that during the training. Yeah.

W: Gerry with toughened glass where it’s going to be heated up to be made tough after you’ve cut it, what about fitting other things that require holes thru the glass like hinges and handles and things?

G:  Yeah, they’re all drilled out or cut out first before the toughening process. Once the glass is toughened, it can’t be worked in any way again. If it’s wrong, it goes in the bin and start again. So all that cutting and checking out has to be done first including polishing the edges etcetera and then it goes thru the toughening process last.

W: I see. And once it’s been thru that process if you attempt drill it or cut it, it will just shatter.

G: Yeah, correct. Any work will just break it.

W: Now Gerry safety glass is obviously more expensive than ordinary glass that hasn’t been toughened or laminated, where do you have to use safety glass?

G: Anywhere there might be danger of human impact as they call it. So it would be in a door or next to a doorway or any opening that could be mistaken for an unimpeded path or walkway that somebody could walk into it. So you would use Grade A safety glass there or in shower screens and balustrading, all those areas where people can walk into it are by large safety glass.

W: I know that having non-safety glass in those passageways can be very dangerous if somebody does walk into it and break it because it breaks them into large shards that cut them and cause them horrendous injuries. Is there any way to tell what is safety glass and what is not safety glass? Perhaps if I’ve just pulled up an older house or it might be my parents’ place who’ve had glass in there for a long time, how do I tell which is which?

G: Usually with the toughened glass, one of the bottom corners you’ll see a stamp like a manufacturer’s or toughener’s stamp that tells you it’s toughened. But we have a meter that we can go out also and audit people’s properties and check if it’s safety glass or isn’t because sometimes as well it’s not stamped or the laminated is seldom stamped so we can check thru our meter that it’s Grade A safety and then certify it if it is.

W: Gerry Whelan it’s been a pleasure talking to you again. You’re a font of wisdom when it comes to things glazier-related. Thank you for giving up your time to us today.

G: Thank you very much Wayne, always a pleasure.


 

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