A modern building, but outdated windows

Built in 1992, Selectaglaze HQ is a 2-storey curtain wall building. In spite of its relative youth, the glazing was simply not good enough. As with so many modern office buildings, the existing double-glazed units didn’t meet modern energy efficiency standards. They are a mix of thermally broken and non-thermally broken metal windows, with unimpressive U-values of 3.3 W/m2K and 2.2 W/m2K respectively.

Not out with the old

You might think that it would make sense to strip out these substandard windows and replace them with new high-performance units. However, as sustainability champions with ambitions to be a Net Zero business, this was never going to be an option for us. We’re staunch supporters of the Retro First movement to retain embodied carbon in the built environment. So that’s precisely what we did, installing our own bespoke secondary glazed units, with low-E glass. This was a doubly successful sustainable solution – improving U-values, while keeping our carbon footprint low.

Sympathetic, sustainable solutions

We installed our Series 10, Series 80 and Series 15 horizontal sliding systems, painstakingly matching the sightlines, style and colour of the existing windows. Naturally, we make every effort to keep our products as sustainable as possible – with an increased overall recycled content of 43%. We’re proud of the longevity of our products – with a life expectancy in excess of 50 years. And at the end, they’re 99% recyclable.

Improved thermal performance

The difference made by secondary glazing meant that Selectaglaze HQ has become a warmer, quieter place to work. Most impressively, we were able to cut the U-value of the more dated non-thermally broken windows from 3.3 W/m2K to 1.5 W/m2K by installing secondary glazing with hard coat low-E coated glass. For the thermally broken windows we achieved the U-value improvement from 2.2 W/m2K to 1.25 W/m2K.

Maximum impact, minimum disruption

All of this was completed without the need for scaffolding, time, money and waste that comes with wholesale window replacement. In fact, it was business as usual for our people. So if you’d like us to do the same for your business, get in touch.