Demolishing the flue without permission is an act explicitly prohibited in the relevant laws and regulations of national building decoration, and there are hidden dangers, so it should be restored, otherwise it will be punished by the property or housing supervisor. Suggested treatment methods are as follows:

1. Post-embedded parts are added at the top smoke outlet of the kitchen to support the flue above the top smoke outlet.

the embedded parts can be made of a steel plate (8-11mm thick) with a size of 1.5-21 cm larger than that of the smoke crossing, and the middle part slightly smaller than that of the smoke crossing is cut off. Then punch expansion bolt holes around the steel plate, and fix them firmly with the top floor around the kitchen smoke crossing with expansion bolts. The purpose of this operation is to prevent the flue on the roof from collapsing and damaging the flue under the top floor.

2. Use light steel keel to build the frame, and then fix the cement board on the light steel keel as the main and auxiliary flue. Be careful not to use wooden keel as the skeleton. Second, the bottom of the frame of light steel keel can only be fixed on the ground floor, not on the top of the flue downstairs.

3. plaster or roughen the cement board by hanging the net, and seal the contact part between the cement board and the top of the wall.