You have an absolute responsibility under the terms of the lease to repair the structure of the building under the terms of your lease the landlord is telling you, which would include the roof. If that’s the case then this is the situation:
However if the workmen have damaged the roof during the course of whatever it is that they were doing, then you have the right to offset those costs against the amount of damage caused by the builders. If the roof was in perfect condition before they started, they are liable for all the cost.
If the roof was in less than perfect condition, then they would be responsible for part of the costs depending on how much of the work would have been required in the near future in any event.
You have to decide whether you owe money or not in respect of this and then offered to pay that to the landlord. If the landlord decides to sue you for the cost of the damage because you have not paid it, then you will have to defend his claim or defend part of it and bring the builders in as second defendants to the claim.
Don’t necessarily take your landlord’s word for it however you are responsible for the roof, you need to check the lease to make sure that you are responsible because the landlord may be simply trying it on.
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