Given that your builder denies even going onto your neighbour’s roof in the first place, the onus here is on your neighbour. He must be able to able to prove that your builder was the cause of his current roofing problems.

Broken tiles are often caused by bad weather - in particular, strong winds, hail or even heavy rain - or it might simply be a case that your neighbour’s tiles are quite old and that they’ve cracked under the strain caused by inclement weather over the years. On the other hand, your builder’s denials may just be a cover up. You are unfortunately stuck in the middle when deciding who to believe.

Who is to Blame?

However, the only way to have the matter resolved would be for you to suggest to your neighbour that they hire a buildings or roof surveyor to come out and inspect the damage. A professional eye would be able to tell whether or not the broken tiles could possibly have come about as the result of your builder’s activities, if it was more likely to be down to weather damage, or the fact that the tiles were old and needing replacing anyway.

Paying for these Checks

Your neighbour would be able to claim on his household insurance for the costs of this survey to be carried out. Should the surveyor’s findings prove that your builder was negligent then you have a couple of options. You can then either agree to pay for the damage to your neighbour's roof, or you can hire your own surveyor for a second opinion.

In cases where two surveyors may have different opinions, then you could either agree to split the costs of repairing the damage with your neighbour, or make a decision to jointly agree to appoint a third and final surveyor and to stand by their findings.

However, it should be re-emphasised that from the information you’ve supplied here, there is no evidence that you or your builder have been guilty of any wrong doing, so it really is up to your neighbour to prove otherwise.

Going to Court

Your neighbour could decide to take you to court, which should always be a last resort as it can be a very costly affair for both parties. Basically, it all very much depends on how you feel towards your neighbour. If the damage is relatively minimal, you might think it’s easier to suggest splitting the costs of the repairs, as a small financial outlay might mean less hassle all round and will help you to maintain good relations with your neighbour. However, until your neighbour proves any differently, you are under no obligation to pay for anything.