I feel for you so much OP, we moved to our current home just over a year ago, 1950s semi but we suspect there’s no cavity in the party wall and that the joists for the suspended floor and upstairs run through both houses. We wanted wooden flooring but the minute we moved in we could hear banging and screaming from next door’s suspected ASD child and it has never really got much better. If the child is home of a weekend/holiday it’s intermittent screaming/whooping/stimming all day. He has a sensory swing he kicks off the party wall with his feet in, which thuds all throughout our house. Any time he runs or something gets dropped etc the noise and vibration of it travels through our entire house. They’ve also just had a baby so now we hear him set the baby off crying and then it just turns into a crescendo of screaming/crying/banging and the mother inevitably ends up also shouting and it’s a lot to have to put up with when you work full time and just want to have peace in your home (we really are quiet people and just want a peaceful life).
It really affects our mental health and it’s so so stressful - we’ve tried to speak with her about it and she just says it’s part of living next to a family (I think the noise is well beyond normal living noise personally).
They also don’t seem to have carpets or rugs down either which I think exacerbates the issue.
I live with white noise permanently playing on the Alexa whenever the TV and radio are not on to try and minimise the disturbance from the noise. I do have ADHD so while I don’t think my assessment of the noise is wrong as it is excessive and we’ve had visitors comment about it, I do think the way it makes me jump and I then can’t tune it out makes the impact a lot more severe.
We have decided we need to save to move to a detached house ASAP for our own sanity. I’m gutted because I sold my last house after a 4-man machete break in happened in the adjoining house and it turned out the mother had left the kids in on their own so I went in when the men had run off and the house was filthy, full of drug paraphernalia and animal faeces. I’ve been a childrens social worker in the past so was nothing I hadn’t seen before but it brought back a lot of trauma from the job and even though those tenants moved out after that, I could not face living there. I’ve come to realise any house attached to another has the potential for noise/disruption beyond what I’m willing to tolerate.
Not sure if this helps but I really do feel for you OP 🧡