We have a JCT minor works contract with a value of £286,000 after we signed the surveyor acting for the client omitted the supply and fit of the windows valued at £17,400 and gave the works to a cheaper company can we claim for oh&p on the £17,400 ?
Under JCT works can be omitted as there is an express variation clause allowing omissions (without an express clause then there is no right).
However that right cannot be exercised to remove works and give them to another company - it can only be used to omit them altogether.
The contract you signed gave you the right to carry out all the works for the price agreed. You can bring a claim for breach of contract as your employer cannot omit works to get them cheaper elsewhere. Your damages are to put you in the position you would have been in had you carried out the works ie your profit on those works.
Whether you can claim overheads would depend on whether you can properly link those only to the omitted works.