Where are we now with triple glazing?

It’s been three years since Edgetech hosted the Triple Glazing Question (TGQ) and brought together delegates from the whole glazing supply chain.

At TGQ, there was a great argument made for using ‘clever doubles’ instead of triple glazing, especially as there were concerns about the manufacturing complexity of triple glazing and lack of availability for units and appropriate profiles.

Head of marketing at Edgetech UK, Charlotte Davies said: “With such good performance available from double glazed units, it was argued that an extra pane of glass wouldn’t necessarily be an improvement.

“However, since TGQ we have seen instances where the additional thermal efficiency from triple glazing is the better option, such as in super insulated buildings, where there are significant gains to be made by choosing U-values of 0.8W/m2K — easily achievable with triple glazing. Plus, the massive increase recently in sales of bifolds and sliding doors means that there’s a lot more demand for big units. Some of these can greatly benefit from using triple glazing also, as with such vast expanses of glass it can make a real difference to the comfort levels in a room.”

It was confirmed at TGQ that the centre pane should be toughened because it can become very hot within triple units, especially if they are fitted in a building in the full glare of the sun. But the elevated temperature can have other ramifications too.

“The temperature within triple units can easily exceed the maximum required of volatile fog tests in current European standards,” Charlotte said. “This means there is a risk of fog appearing within units from spacers, which are not compliant to higher international standards, giving off volatiles when overheated. This isn’t a problem for Super Spacer as it is installed in units from Alaska to Dubai and tested successfully from -15°C to 125°C, so you can be sure it will perform in UK triple glazing.”

Other advances since TGQ include developments in automated IGU manufacturing and the addition of profile options to accommodate triple glazed units by most window systems companies.

“Aesthetics are taken care of automatically too,” Charlotte said. “Whereas rigid spacers are often lined up manually, Super Spacer is applied by referencing the edge of the glass. The two spacers line up perfectly so units made with Super Spacer always look symmetrical. Plus, Super Spacer’s acrylic side adhesive means there’s no need to apply a PIB primary seal, removing risk of smearing inside the unit.

“Three years on we can see increased production of triple glazing and we know that there’s now manufacturing capability in the market for high performance triple units without compromising productivity or aesthetics. There’s not been a switch over from double to triple – but the trend continues to grow, especially where high levels of performance and energy efficiency are paramount.”