After all that wattle and daub stuff, someone invented the brick wall. In the 1930s someone else invented the cavity wall, which trapped an insulating layer of air, but was still cold in winter. More recently someone realised injecting the air cavity with an insulating foam was even better.
In the last few years, about 30 year after the rest of Europe, the UK Government finally adopted building regulations to require proper home insulation in the first place! Continue reading