It is a pity to see how many original sash windows are getting replaced today while there is a way to save them and improve their energy efficiency by replacing single glazing with 7 mm vacuum double glazing.

Just compare the look of the new double-glazed sash window and the old refurbished window. The original windows with new vacuum double glazing look sleeker and preserve the charm of a period property.

Sash window secondary glazing compared to original sash window with vacuum double glazing

Vacuum double glazing vs other glazing options

https://chameleon-decorators.co.uk/sash-windows-double-glazing/