I know a lot about flues; I have always relied on a fire or a stove for heat to a greater or lesser extent. Living and building in Wales has taught me a lot about the ways that flues work – or don’t.  Sometimes the flues I built just needed a little extra height to make the desired forces work in my favour. I gather from this photograph that the inhabitants had over the years had to add a little bit of height – just to clear the height of the ridge of the roof. 

Lugo, Spain – October 2006