It will depend on the nature of contract. If JCT or similar type has been signed then the contractor should have seek approval prior to any additional works from the Architect for the variation. If no such permission is granted then as you say the contractor has proceeded at his own risk. Ofcourse the builder has violated the clause "dicrepancies reported to the Architect." Also, it will be very difficult and expensive for the client to take such legal action if he has to prove negligence under law of tort. Claiming insurance is another option, but it will make your premium expensive in future.

Always sorry to hear of such a case, as the stress caused can be immense. Yes the contract type is critical, but I would write a polite but firm letter to the Client outling the facts. This letter should make it clear that you will vigorously defend any claim. Obviously run this letter past your insurer before issuing, and if possible/affordable use a specialist claim company such as Greyhawk to assist. If as it seems you are in the clear then you can afford to be bullish in your defence. It is likely that your client is acting on poor advice from a poor contractor in seeking to get the money from you. It may be that your client has being bullied into paying the contractor the additional money on the basis he can claim it from you. Lastly, I would investigate the builder and make a complaint to Federation of Master Builders or whatever else he belongs to.

Thanks for taking time to offer some advice. As it was only a small extension i would doubt there was any JCT contract in place or similar between the builder and Client. One other point of interest is that the builder approached me a few weeks before to change the extent of the slab. This was obviously a benefit to him and no doubt a cost saving. I agreed to amend my drawing to take this into account. My work on the project was completed long before this. I also agreed to do it for no addtional fee (that my appear stupid now but sometimes difficult to ask for). Anyway with the afore metioned occuring I did not complete this and Building Control have told me that it is not stopping the completion notice. However, the client is also mentioning in his letter to me that I agreed to do it and for nothing and it is required for Building control to finalise their records. My Fee for the project was only £475+ vat (design and Detailing of raft, A steel beam over an opening, plus design of 3No masonry piers. Yes i can hear what you are saying and yes did make a loss!

It seems fair to say that you weren't given the opportunity to address the situation, and the builder proceeded at risk resulting in extra cost to the client. As JB says, the client seems to have accepted this cost and paid for it without reference to you. The threat of taking this to ISE is lame, as I think is the claim at this stage, and I think once the client is aware of potential solicitors costs he has to stump up in chasing you he'll back off. Not sure I'd lose sleep over it, but I appreciate you won't want damage to reputation.

Update.... Following a conversation with the FMB plus poor sleep and the thought of lining lawyers pockets at £100-200/hr i decided to take the bull by the horns and spoke with the Client on the phone. In short he feels he has no come back on the builder and thinks the builders claim for the extra was justified. No 'Contract' in place, and the builder took no direction or approval from even the Client. He just carried on and put in an extra bill! In a bid to move on I have managed to agree to pay the Client back half (£630).He is quite relaxed about if I dont pay then will take me to the small claims court. He even feels sorry for me! but never the less holds me responsible. I feel infuriated with the builder but my contract was not with him. So I will have to take the hit. The builder is not someone I have worked with before but 'my' local builders would have never done this......the times i have pulled builders out of the ---- in the past at no cost to them. An expensive lesson learnt Finally many thanks Guys for your kind advice.

Mr Brigstocke, I appreciate that this has caused you some distress and a resolution is good in that respect BUT... 1) talk to your insurer beforemaking a "deal" like this. You are admitting liability. 2) if details are as stated, you could defend this yourself in small claims court. 3) the sum being claimed is clealry inflated in the first place. even the 50% you are offering is more than the cost of the alleged additional work. As I said at the start, I sympathise with your reasoning for doing a deal but unless you stand up for yourself you will be placed in this position again and again. The Client is just suing you because he cant sue the builder??? That said, it is a good idea to have a standard note along the lines of "IF IN DOUBT ON ANY ITEM OF BUILDING STRUCTURE - CONSULT STRUCTURAL ENGINEER. NO ADDITIONAL COSTS WILL BE ACCEPTED ON STRUCTURAL ITEMS UNLESS QUERY HAS BEEN RAISED WITH STRUCTURAL ENGINEER PRIOR TO UNDERTAKING WORKS"

Firstly, I would applaud your bravery in opening a post on this topic. I am of the opinion this type of thread should be discussed more on this forum. (much more interesting than that 9/11 tosh). And while I am aware that the only opinion that matters is that of the ‘gentleman in the wig’, my opinion on this issue is: By your own admission you have accepted that you have dropped a clanger. Your qualification on the drawing stating “discrepancies shall be notified to the Architect” is not a condition of any contract. The qualification can only be viewed as a ‘hold point’, to stop work until a suitable solution is arranged. Determination of that solution is not within the remit of a Contractor. The Contractor should have stopped work and sought advice from you. For all the Contractor knows, you could have got some new bars bent and supplied them to him free of charge. (You will have to assess if new links would have been less expensive than £1260). As you mentioned, the most cost effective solution would have been to position the shear links on a slant. Thus I would estimate the extra cost associated with the additional time taken to tie and place a reinforcement cage with links on a slant, and offer that to your client. (Two blokes taking say 1 hour at £30 per hour is only £60). I would suggest that is fair and reasonable, and I think would be supported by a magistrate at a small claims hearing. If you’re feeling really tough, you could then counter claim for the defence of scurrilous claims and reduce the offer by £40 for an hour of your time. I, also wouldn’t worry much about the claim through the small claims courts until your client actually approaches the court. When your client finds out that he has to pay for the costs of the court case, he will certainly have second thoughts. In the small claims courts, I believe costs are borne by each party. The costs associated with bringing an action against you will far outweigh the £1260 he is wanting from you. You can defend yourself; which will cost you nothing. Your insurance company will also defend you. If you win, that will also cost you nothing and notification to your insurance company will also cost you nothing. I have to admit, I would be more concerned with the threat to complain to the ISE. I am not too sure how the ISE would view a case like this, but my gut feeling is they would tend to side with “that little old lady with the blue rinse”. The guidance notes on the ISE website gives examples of conduct that may be regarded as breaching the laws of the Institution. Bullet point 2 states “Failing to discharge their duties with care, courtesy, impartiality and fidelity”. What does that mean, if not dropping a clanger? So in summary, I would tell your client to sling his hook. The decision to dig deeper was not the Contractors decision to make. (what would have happened if that was structurally the wrong decision to make). I would make your client a reasonable offer to refect the additional works associated with tieing links at a slant. I would review the consequences of the additional mass of concrete wrt crack widths, loading etc and tell him that you are not responsible for the works as it was not built to your drawings. But the decision is yours and I know it is a tough one. Best of luck. I would also be interested to know if there are any lessons learned that you feel able to post on this forum.

Further update.... Whilst I have no recourse with the contractor I contacted him to ask if he would help with my costs to mitigate my loss. I feel he did not afford me reasonable time to respond. In short he said NO contribution. I am now able to piece together the course of events. He did phone and leave a message on my mobile and Office land line on a thursday. This day I was on a RAF site in Salisbury where mobiles had to be switched off, I even had to hand my camera in! When I contacted him the following morning I was informed they had dug out the extra 100mm to accommodate as he could not get hold of me. 3 guys on site at a charge out of £37/hr!!, a total labour cost incl vat of £1021 ( that's taking the ----). In summary the way unfortunately I see it is my contract was with the client who was satisfied to pay the contractors costs (how ever inflated) and in court he will be seen to have suffered the loss. I feel the best option is to pay out £630 and move on however nasty the taste that leaves in my mouth. JB- thanks for this advice ironically I had already amended my notes along these lines

JB, "... NO ADDITIONAL COSTS WILL BE ACCEPTED ON STRUCTURAL ITEMS UNLESS QUERY HAS BEEN RAISED WITH STRUCTURAL ENGINEER PRIOR TO UNDERTAKING WORKS" Is putting this note on drawings a good idea? It emphasizes the suggestion that extras might be available for the contractor, & unscrupulous contractors might be prompted by this to take advantage of their clients. It might be better if hidden away in the specification, where they won't read it. My standard note on this sort of thing is: 'For general details of construction, refer to Architect’s drawings and specification. Any discrepancies between my drawings & those of the architect or any specialist contractors must be resolved with me, to the satisfaction of the other parties. If in doubt on any item of the building structure, resolve it with me before carrying out the works.'