Having recently moved into a new build apartment, the noise through the
trickle vents in the bedroom window is driving me mad. Ironically, the
spare bedroom (which faces a railway line) has acoustic vents through
the wall rather than trickle vents through the window frames and it is
*much* quieter than the master bed where the trickle vents (even when
closed) let in way too much noise from the nearby road and passers by.

I have been trying to find some sort of acoustic trickle vent to
replace them with but thus far have only found the DN range from
Greenwood
(http://www.greenwood.co.uk/data/DN%2...ta%20sheet.pdf) which
unfortunately doesn't come in the size I need.

Can anyone suggest any others?

thanks,

David