Hi, welcome to Just Answer. I will help you with your question.
In every contract there is an implied term that services will be carried out with reasonable skill and care.
So, you should be able to argue that the standard dropping means that the latest service falls below a reasonable standard (the previous standard having been reasonable), and therefore there has been a breach of the contractual term that services would be carried out with reasonable skill and care.
As such, you would be entitled to deduct a sum from the contract amount.
So in short, yes, you should be able to argue as you mentioned.
The work done by others is recoverable too against the contractor.
Thats because the work is necessary as a result of his breach of contract, a breach of the implied term of reasonable skill and care in relation to his work.
All those things go to quality of the work done.
As for the rate of work done, this is a similar point, in that you're expecting a reasonable rate - the rate before was reasonable, this one is not.
Does that make sense?
Yes Thank you.
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