Each of the six-door types was constructed in a double-sided manner, allowing two folding doors to be opened on both sides.
Although construction with ordinary windows is difficult due to width problems, folding doors can be used in both ways. Opening and closing windows are much more convenient than windows.
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Especially, the view is open, so it is good for ventilation, but vice versa, or the folding door, which has an insulating effect, keeps the room temperature warm during the change of seasons. Especially because there is no building around it to cover up, these insulation problems need to be more careful.
Many years of construction will be completed with a solid construction know-how.