Broken bridge weather

Hello, mildew is caused by poor sealing when installing the window, air leakage at the joint between the wall and the window frame, low local temperature, resulting in condensation of water vapor, and poor sealing caused by poor installation of the window. This phenomenon is very serious in the early stage of heating, and it will improve with heating. If it is outside the warranty period, you can only repair it yourself.

Hope to adopt!