Hello thanks for your patience.
Interest is only payable on judgement and this is assuming she is successful. You should have still used your insurers to raise payment for her, even if she doesn’t have insurance, this is because they will ensure the costs she is claiming for the damage is reasonable.
Needless to say, the liability claim should not be against you but the contractors who did the works. I note you have stated there is no proof and they didn’t want to accept responsibility but this is not necessarily the case as negligence in civil claims like this is assessed on the “balance of probabilities”. It is a low threshold for the burden of proof. Plus, from obtaining documents which showcases the works they did, you can see what was worked on, when, what materials were used etc and extrapolate from that how the damage was caused. Essentially, it is you who has a claim against the builders both in contract and negligence for the works being carried out below the standard and skill expected of a reasonable and prudent contractor.
But to address your question directly, and we can never call how a judge may see it as it all depends on what evidence is presented to support, but it is risky for her to take you to court as the at fault party and be successful. She would need to be able to identify the direct cause of the leak, and the test is was it reasonably foreseeable that this leak would occur. As you are aware you did not carry out the works, so it is the wrong party she is issuing against. Additionally, she has refused your offer to pay through insurance. Courts see litigation as a method of last resort and like to see parties take all reasonable steps to settle matters prior, if she accepted the insurance payout then court would not be necessary and this refusal can be used against her.
I cannot say for certain if she will be successful but from what you have stated I can’t see any legal grounds for her to bring a claim against you. It certainly isn’t negligence and it isn’t contractual either and the only grounds are it was your house and you instructed the builders. This is not enough and something you can defend.
To briefly explain the above; to be successful in a claim for negligence she has to prove that there was a duty of care, that duty of care has been breached, and that breach caused foreseeable loss and damage. Not disputing she suffered loss and damage but you did not owe her a duty of care as you did not carry out the works and if you aren’t to be held vicariously liable for the contractors actions. And you should seek to defend the matter on the grounds it’s the wrong party and have her claim struck out and costs sanction awarded against her for not following the pre action conduct.
I cannot say for certain without thorough investigation of all facts and documents from both parties but from what you have stated this is a claim that should be defended rigorously.
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