During the construction period, if it is necessary to replace the stair tread veneer, it shall be submitted for approval according to the following steps:

1. Submit an application: First, you need to submit a change application to the relevant departments, including the design unit, the owner unit and the construction unit.

2. Feasibility of examination and approval: The examination and approval department will evaluate the feasibility of the change, including whether it meets the design specifications, safety requirements and rationality.

3. Provide scheme: If the change is approved, detailed design scheme and construction scheme shall be provided.

4. Review: The plan needs to be reviewed to ensure the rationality and feasibility of the change.

5. Get approval: If it is approved, it will be approved by relevant departments.

6. Implement changes: After approval, changes can be implemented.