Thermoseal Group has identified a notable transformation in the UK spacer bar market, as insulating glass unit (IGU) manufacturers move away from the long-dominant 20mm airspace. This shift is largely driven by tightening u-value requirements, increased use of laminated glass to meet Document Q, and the growing demand for triple glazing.
Spacer Sizes Adapt to Glass Innovation
“20mm spacer bars used to make up 80% of units,” says Mark Hickox, Sales Director at Thermoseal. “But with laminated glass increasing unit thickness, manufacturers are now opting for narrower spacers, typically 14mm, 16mm, or 18mm, to meet overall unit size requirements.”
Triple Glazing Sparks Broader Range of Spacer Sizes
Traditional triple-glazed units used combinations of smaller spacer sizes to fit within 28mm systems. However, the rise of European-style profiles has enabled deeper units: 36mm, 44mm, or even 52mm, bringing larger spacer sizes like 22mm and 24mm into more common use.
Flexible Production for a Changing Market
To meet this changing demand, Thermoseal has implemented a campaign-based production approach across five UK spacer bar lines. This model allows for seamless shifts between core 20mm runs and other growing sizes without delays or stock issues. 
High-Performance Solutions for Energy Compliance
Thermoseal’s warm edge products: Thermobar and Thermoflex, offer advanced thermal performance. Thermoflex, with a thermal conductivity of just 0.125W/(mK), is certified by IFT Rosenheim and BFRC, helping fabricators meet evolving energy standards.
Source: Thermoseal Group with additional information added by Glass Balkan
