I mean, theoretically, it's a good idea to have full-length lined curtains to keep the heat in and drafts out. Makes sense. So far so good. But in the UK we tend to have radiators fitted directly below windows. So if you close your curtains while the heating's on, surely a lot of the heat is going to rise up behind the curtain and escape through the windows. And that's not exactly efficient in terms of energy or cost. In the bedroom with full-length lined curtains, I tend to close them then lift them and leave the bottom half of the curtain crumpled up on the windowsill so the heat circulates round the room better and isn't wasted heating the gap between the curtains and the window. Am I doing it wrong? The set up seems wrong to me. Is there a reason that escapes me why it might be a good idea to have your heating on with full-length lined curtains drawn and heat going up behind them? It doesn't make sense to me, but is there a reason why people do that?