total width of all visible, contiguous columns occupied

Try this:

Sub total_width()
Dim totalwidth As Double
Dim n, i As Integer

totalwidth = 0

For n = 2 To Sheets.Count
    With Sheets(n)
        For i = 1 To 15
            If .Columns(i).Hidden = False Then
                If Not .Cells(1, i) = "" Then
                    totalwidth = totalwidth + .Columns(i).ColumnWidth
                End If
            End If
        Next
    End With
MsgBox totalwidth & " Total Width of Columns"

totalwidth = 0

Next

End Sub

ska