Is a clay house only possibile in warmer climates?

In the province of Alessandria, in Northern Italy, there are entire buildings that were made of clay over the past centuries and are still habitable. Ait Ben Haddou, a city that is a UNESCO World Heritage site, has been entirely built using raw dirt in the Marroccan inland. When we went to visit it, the guide told us about the minimal maintenance requirements of clay buildings. One curiosity: newlywed couples can choose if they want to receive a green or red clay house as a wedding gift.