Why are the roofs of buildings in the north flat?

There are many reasons for the flat roofs of buildings in the north, one of which is the climate. Because of the large annual temperature difference, the houses in the north are cold in winter and windy and dusty, and the houses are built into flat roofs, which is convenient for heat preservation. At the same time, many buildings in the north are built in the lee, and the windows are open in the lee.

in addition, there is abundant rainfall in the south, and failure to make a sloping roof will cause water accumulation, which will increase the load of water accumulation on the roof and affect the service life of the house.