Britain has a wonderfully rich stock of period houses - everything from medieval cottages to Georgian townhouses and Edwardian mansions. But many of these historic properties are now at risk. Some are unwittingly damaged by well-meaning owners or incompetent builders; others suffer long-term deterioration where mortgage lenders have imposed quick-fix 'remedies'. Despite being some of the most sustainable buildings on the planet, many old houses are now being subjected to ill-advised works to upgrade thermal efficiency, resulting in the destruction of the very qualities that make them so...