Sub InsertRowBelowOnes()
Dim LstRw As Long, Rw As Long
Application.ScreenUpdating = False
LstRw = Cells(Rows.Count, "B").End(xlUp).Row
For Rw = LstRw To 1 Step -1
If Cells(Rw, "B") = 1 Then Rows(Rw + 1).EntireRow.Insert
Next Rw
Application.ScreenUpdating = True
End Sub