Hide/Unhide Rows

[Hooty]

I found some Useful code, but i need it to do more.

[code]
Private Sub Worksheet_SelectionChange(ByVal Target As Range)
If Range("B4").Value = 0 Then
Rows("14:16").EntireRow.Hidden = True
Else
Rows("14:16").EntireRow.Hidden = False
End If
End Sub
[code]

if i add rows above this code it adds the next row in the range to the hide list, but never unhides the additional row.

Needed:

I want to hide certain rows that do not need to be seen until a value is entered elsewhere.
I want to apply this to several sets of rows, even if i need multiple macros.

The rows that i want to hide will be located below the main body of the report, so row numbers will increase constantly however;
No rows will be added to the hidden selection, only values will change.