As I understand, typical UK domestic windows have trickle vents to try to allow warm, damp air to escape a room (and cold, dry air to enter) to avoid or reduce condensation on the windows.

Now what I have never understood is, and does anyone know if there is hard data on this,

1) Say you have fabulous high-tech glass, triple-glazed, argon-filled units with thermal barrier window frames, all professionally installed, what percentage (typical UK weather conditions) of the "heat saved" is then lost through the trickle vent?

2) Can the windows be sealed as tight as a drum to limit air exchange through them to a minimum - but the ventilation requirements be met using a through-the-wall ventilation unit? the advantage of these being as I understand is they heat the incoming air via a heat exchange to limit heat loss and the effects of inbound cold air triggering condensation?

3) What do the Scandinavians or Icelanders have installed in their glazing units? Do they have trickle vents in the frames? Is there any research on their experience of window pane or frame condensation?

I will declare my prejudice that I suspect trickle vents are a lazy, counter-effective solution to condensation and there are "better" solutions - but I am very happy to be shown to be wrong in that prejudice.

Ta,

Clive