Is it hot in summer in the Forbidden City? How did the ancient Chinese escape the summer heat?

    Anyone who has visited the Forbidden City will be surprised to find that although there is no air conditioning, it is exceptionally cool, especially under the eaves of the palace. Why on earth? In fact, the secret is hidden in the Forbidden City buildings. These golden roofs cover an area far larger than the building itself, and the corners of the roof rise up like the wings of a bird.

    This design is not only for beauty, but also for the practical purpose of facilitating the daily life of ancient people -- in summer, the midday sun would be blocked by the eaves to achieve the purpose of shading and cooling; In winter, the slanting sunlight can penetrate the interior of the palace and drive away the cold. This is because the sun shines at different angles in different seasons. Ancient craftsmen summed up the law that the Angle of sunlight in Beijing changed with the seasons, and cleverly designed the roof structure with both aesthetics and practicality. 

    In addition, the choice of building materials on the roofs of ancient buildings in the Forbidden City is also very exquisite. On the board base of the roof, a layer of 30 cm thick mud back is usually laid. These mud back is composed of board ash, green ash, knife mud and other materials. These materials have good heat insulation and thermal insulation performance, and can absorb a lot of heat from outside and avoid excessive heat directly into the room.
    In order to better dissipate heat, some important halls of the Forbidden City will have double-eave roofs. This structure forms an overhead layer between the roof and ceiling of the ancient building, which can intercept the solar radiant heat directly shining on the roof, so that the roof becomes a double heat transfer and avoids the direct effect of solar radiant heat on the building interior. In addition, because the hot air has a rising trend, indoor hot air will rise and accumulate in this overhead layer, avoid direct contact with people.

    But to really feel the heat in summer, you need not only to be protected from the sun, but also to have a cool wind. Here we have to mention the Palace Museum's ability to borrow wind from nature.
    Ancient Chinese buildings are often in the form of "architectural complexes", and the surrounding environment is also considered in the design of the "architectural complexes". The Forbidden City is a good example.
    The Forbidden City is surrounded by the first three seas (South China Sea, Middle China Sea and North Sea) to the west and Jingshan Mountain to the north. In summer, these gardens form a natural "low temperature and high pressure zone", trapping cool air here, which makes the palace especially cool.  

    In addition, pergola and ice were set up in ancient imperial palaces to cool off the heat.