Window system meeting different functions of existing building transformation and construction method

The invention relates to a window system meeting different functions of existing building transformation and a construction method, belongs to the technical field of building transformation, and solves the problems that in the prior art, in the building transformation process, new materials are used, the style and appearance of an existing building are damaged, and energy conservation and environmental protection are not achieved. The window comprises a window unit, the window unit is arranged in a window opening of an existing outer wall, the window unit comprises a first window unit and/or a second window unit, the first window unit is used for meeting the indoor lighting requirement after building transformation, and the second window unit is used for meeting the indoor ventilation requirement after building transformation. The requirements for lighting, ventilation and heat preservation are met, resources are saved, and the existing green building efficiency is achieved. 本发明涉及一种满足既有建筑改造不同功能下的窗户系统及施工方法，属于建