My non resident neighbour (semi detached houses) mentioned that as part of extensive building works they were planning to remove a chimney breast on the party wall. I had half an hours free advice under the RICS scheme and was advised the neighbour would have to serve a party wall notice. I mentioned this to neighbour who blustered that architect had not told him but would look into it. about two months have passed and we have heard absolutely nothing from them until the builders arrived to start work. So no notice has been served. DH thinks we should say nothing but what if there any problems. There were other structural works along party wall which he did not detail but we expected to see in notice. Any advice?