……………with foam?. We have a shower pump fitted in the airing cupboard which adjoins a bedroom and makes one heck of a noise when someone is showering and someone else is in the bedroom is trying to sleep. Between the airing cupboard and the bedroom there is part of the dividing wall with a totally enclosed gap between both being around 2500mm high, 950mm wide and approximately 100mm deep. I got the idea that if I filled this gap from top to bottom with some sort of expanding foam, the noise from the pump would be cut dramatically. If that idea is sound, perhaps there are other, perhaps easier ways to fill the gap. Either way, I would be grateful for any advice. Two final points: (a) the noise appears to be mainly from the the vibration from the pipes feeding the pump which are mounted from floor to ceiling on the airing cupboard wall and (b) I have never handled expanding foam before. Thank you.