The demand for triple glazing is increasing now as homeowners and developers seek to future-proof their homes by improving the thermal efficiency of building products.

“One volume housebuilder in the Southwest is now installing triple-glazed windows into all new starts,” Cornwall Glass Manufacturing’s Joint Managing Director Mark Norcliffe said. “This is starting to feed through to our manufacturing output.”

Mark said Cornwall Glass Manufacturing has seen orders for triple glazing increase at one site by 100% since the start of the year. Our IGU manufacturer’s Plymouth site is geared toward making high-value products, including technically challenging and oversized units. Since triple glazing falls into that category, those orders are often fed through to that site.

“Triple glazing now accounts for more than 10% of our order volume,” Mark said. “And the sales value is even higher.”

The evidence points to homeowners and developers using triple glazing to help keep running costs low and to meet expected changes to the Building Regulations.

“Windows going into newbuild homes from 2025 onwards are looking to achieve U-values of 0.8W/m2K, according to the proposed Future Homes Standard (FHS),” Mark said. “While the FHS doesn’t apply to refurbishment projects, we can confidently expect the values to drop much lower than the 1.4W/m2K they are at the moment.

“There is nothing to suggest that current window designs can meet those new levels with double-glazed units, so triple-glazing is a given. The question now is: Are you prepared to handle that extra demand?”

Cornwall Glass Manufacturing is already geared to making triple-glazed units and we have invested in machinery across our sites in Plymouth and St Austell to meet increased demand, and to maintain high levels of quality.

This includes a £1.5 million Bystronic Sealed Unit Line at our St Austell site, replacing a similar line installed 20 years ago. The new line is designed to manufacture triple-glazed units, incorporating online silicone and polysulphide application, alongside gas filling, speeding up the process and maintaining high-quality standards.

And a new heat soak oven recently installed at our Plymouth site, supplied, and installed by Peter Lambert, helps the regional unit manufacturer guarantee its products against spontaneous breakage. It can handle units up to 4.2m x 2.7m.

This is in addition to an extra £20 million. Cornwall Group has committed to spending on new property, machinery, specialist fleet vehicles, and other new equipment over the next two years, announced in July.

Cornwall Group, which includes Cornwall Glass Manufacturing, Mackenzie Glass, and commercial glazing and retail arm Cornwall Glass & Glazing, has secured additional finance via its bank to enhance a stable base from which to grow further.

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