Although you seem to have dismissed it, it is the Party Wall Act that protects you from this nutter. Unfortunately it is civil matter and you can't get the police or Building Control to take the matter on your behalf. Did you look at the link the first replier gave you? In the middle of that weblink is another link that takes you to a Government produced booklet of about 20 odd pages (with a crimson cover). Read it - particularly Part 3, which covers rights of adjoining owners, and especially clauses 19 and 33. If you going to do this on your own you need to formally write to him. You can do the same using solicitors but it will start to cost you money. You may get this back later. You can a court injunction if he fails to co-operate.
If you are going to do it yourself, it could say something like:
Dear so-and-so, regarding the proposed building work that you intend to undertake, I consider that the Party Wall Act 1996 applies and that I am an adjoining owner. This entitles me to the following rights: (quote what Clause 19 says). I am therefore formally requesting you to stop work now until a process of using the Act is established between us. You could add, in the event that you do not comply, I intend to use apply for a court injunction.
The alternative,as you say yourself, is to move house. It is unfortunately that the law appears stacked against the good guys when it comes to these sorts of disputes. Regards, BM