We love when Kevin McCloud revisits what was an unfinished Grand Designs house build ... The race was on to clad the walls and roof in red-tinted, exterior-grade cement particle boards ...

In 1858, William Morris, a 24-year-old architectural draughtsman with some family money, bought an acre of land in what is now the south-east London ... house-painting party. They covered walls ...

And the rehang at the National Gallery departs from red and green spectacularly in places, and particularly in the Renaissance section, where the paintings are radiant—against walls of dark blue.