Simon Gardner wrote:

Whilst I understand that old-style single or double glazing may be
direction of heat-transfer neutral - what about the newer glasses now
compulsory in double glazing? Does this in any way act in a one-way manner
so as to exacerbate the heating effects of a lot of sun as compared with
older glazing?





I think not. The idea is to keep heat in in winter and out in summer.

Its not made, and cannot I think BE made, directional.