Natural ventilators are widely used abroad. For example, in Europe, natural vent must be installed regardless of whether the building is new or old. Because the law has clear regulations, the regulations set digital requirements on how much ventilation area is required for residential living rooms, kitchens, bedrooms and other rooms.  Since the reform and opening, China's economy has developed rapidly, and foreign natural ventilation system have been gradually introduced into China. Different smoke ventilator has also entered people's field of vision.

Building energy conservation cannot be based on the condition of damaging the air quality. Some areas adopt measures to limit the air exchange rate, but excessive reduction of the air exchange rate will inevitably reduce the indoor air quality and affect the comfort of people's lives. Mcwell natural roof ventilation advocates energy saving and emission reduction. It uses the principles of wind pressure and heat pressure in its design to maintain good indoor air quality without power, ensure environmental air safety, and protect people's health.