At our ongoing project near Wollaton Park, the original timber windows of an approximately 125-year-old home have very limited space for replacement glazing. The shallow glazing rebates cannot accommodate the conventional double-glazed units considered for this installation.
10mm vacuum glass fits the available space
Our solution is 10mm vacuum glass. Its thickness suits the available space in these timber frames, allowing the single glazing to be replaced while retaining the existing wooden windows.

Thermal performance in a slim unit
The selected 10mm vacuum glass has a stated glass U-value of 0.5 W/(m²·K). A lower U-value indicates less heat transfer. On the same glass-only measurement basis, this is better thermal insulation than a triple-glazed unit with a U-value above 0.5 W/(m²·K).
Triple-glazing specifications vary, so comparisons need to use equivalent measurements. The glass U-value is not the whole-window U-value: the timber frame and installation also contribute to the performance of the finished window.
Retaining the character of older homes
This project demonstrates a way to upgrade glazing where the existing timber frames offer limited depth. Suitability is assessed against the individual window, its condition and the installation details.


View the project progress photographs, or contact Trent Glass to discuss vacuum glazing for your existing timber windows.





