Grunff wrote:
Hi all,

Anyone know where I can get k values for different types of windows?
Specifically, I'd like to compa

- single pane leaded windows (real leaded, with the lead all the way
through, not stuck on) in a steel frame

and

- 18mm double glased sealed units in an oak frame

The second will win.



As to the leading - it's largely irrelevant.
Glass has a K of 1, so a 6mm pane has a U value of 1*.006= .006.
The air sitting next to the inside of this utterly swamps this in
insulation.