If an extra pane of glass is put in with a large gap between it and the other panes, that should reduce the external noise. However, if trickle vents are put in for ventilation, some noise will get in as well.What is the ventilation problem?
That will let the noise in.Opening a window normally helps I found
Such people don't mind preventing much air entering the room from outside.Don't most people seal trickle vents to stop draughts?

You are overthinking.However, if trickle vents are put in for ventilation, some noise will get in as well.
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