Asking those who may know why I keep getting this warning and what is wrong with what I am doing.
Also, when I try to input the succeeding floor levels (5.5, 8.5, 11.5 and 14.5), the same warning still pops out.
Can you please upload the staad file?
8422.std
There is no floor in your model at height 2.5m, that's why this message is reported. Use a height value of 0, 3 or 6 meters to assign a floor diaphragm properly. The Height value in the Floor Level is the actual Y coordinate of the floor.