There’s no fighting it, summer is over, we’ve given up hope of an Indian Summer here in the Lake District, and are resigned to enjoying a cold and colourful autumn. Time to start saving the pennies for a ski holiday. And to start draught busting all over again. If you have a large hole with a long tube attached to it designed to suck air out, warm air will be lost from your house. Warm air doesn’t just rise passively up the chimney, they are designed to draw waste air out.
The amount of air lost is difficult to quantify as there are so many variables: the temperature inside, the temperature outside, the length of the chimney, where other leaky areas are in the house. However by plugging the chimney throat with a thick wad of felted wool, it is obvious that a large amount of the heat will be prevented from escaping, and will stay where it should: in your room.
The Chimney Sheep™ is a simple and effective way of reducing chimney draughts. I am now going to dig out my door draught excluder, it is one that I built myself stuffed with off-cuts of wool felt and it is like sand-bagging the door against draughts. Door curtains are also very effective at reducing draughts; a heavy lined curtain is ideal but the door wouldn’t open properly, so I use a voile which although is light and filmy is surprisingly effective at blocking draughts. I suppose it works like silk underwear.