Pics below show a bedroom sliding door, a 2nd bedroom window, and then example felt seal for sliding door and the seals on the window. I'm not sure if replacing the seals will do anything (on the window they look to be fine)? There are trickle vents but I don't think they are the only source of the noise ingress.
Replacing frames I have to get permission from ripoff freeholder because all flats need to look the same. I'm aware acoustic glass may only make a few extra db difference. I can't put secondary glazing on the window as it opens inwards, unless I use acrylic and magnets around the inner casement edge (which would look terrible). Secondary glazing may be possible for the sliding doors but will kill resale value and I'm already massively down, sigh. any tips welcome.
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