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Not used any myself, but was thinking along the lines of this?
https://industrialsuppliesco.co.uk/products/sound-proofing-and-deadening-rubber-sheet-linear-meter?variant=42370839806186¤cy=GBP&utm_medium=product_sync&utm_source=google&utm_content=sag_organic&utm_campaign=sag_organic&gclid=Cj0KCQjwpcOTBhCZARIsAEAYLuXLwdP9ssugIMqxJusbTs0X6_QEQPcIQdNcsKyXk9ZwOibqEo8p1DAaApfDEALw_wcBDid something similar with the back of the front door in an old flat, but using acoustic foam and it worked quick well to keep the noise from the stairwell out.
Yep. Any specific suggestions for the material?