Hello, thanks for your question.
My name is Tony, I can assist with this.
Are you pretty sure the problem is coming from your neighbour's property?
So logically, you would say the problem must be coming from the neighbour (or rather, your surveyor would say that)?
Okay. Then there are rights for you to gain access to your neighbours land/property in order to inspect and maintain issues on your land. These are under the Access to Neighbouring Land Act 1992.
however, to enforce the rights, you need to make an application to the Court.
It's not ideal, but sometimes, if you point out to your neighbour that you have these rights, they often let you in, rather than be faced with a court claim which will succeed and they be ordered to pay the costs of having to do that.
You can make an application under the Act using Form N244 and then issuing a Claim Form N1. However, before doing this, I would encourage you to point out the law to them, as they often relent and allow access. If this fails, it might be quicker and cheaper to get a solicitor to do a quick letter pointing it out to them - people take solicitors letters more seriously sometimes. After that, then Court is an option.
The Court does have jurisdiction to order intrusive testing and can, therefore, require tiles etc. to be removed. As for who pays the costs, it depends, if you're right, then they should have to pay the costs and if not, then you will most likely. Costs are always in the court's discretion and reasonableness in all of this is a massive factor.
Does this answer your question?