Structural engineers costs

Mish_Mash

Hi 

I am looking for some consumer advice. I engaged a structural engineer to carry out some work for me on my kitchen extension. Costs were agreed at £2500+VAT. The contract stated that the engineer would advise of any additional costs/work and would seek prior agreement before doing the work. Inevitably there were changes and additional work. That is not in dispute. However the structural engineers behaviour was really appalling in terms of responding to emails/calls, never sought approval for additional work including queries raised directly by the architect (without my knowledge). He also never confirmed timescales for delivery of new work or provided cost estimates which caused significant stress on site as we had builders without work for 4 weeks and they threatened to walk off site (understandably).  

The  structural work completed in Sept last year and I have been chasing on a nearly daily basis for a view of costs so I can settle up. I have never received a call or email and have been tearing my hair out as he had also failed to provide the calculations for buildings control (who were threatening to terminate our application due to the delay). The engineer eventually came back to me in late Feb and the costs have increased significantly.  He now wants nearly 10k. 

I am not rich. I do want to settle up and pay for the work that was done but I feel that I am in a very difficult position as he hasn’t been transparent about the cost increases, he has afforded me no opportunity to accept or reject costs/additional work and he has now invoiced me for the work so I feel under pressure to pay even though I am really quite angry about his behaviour and the position I find myself in financially. 

Do I have a leg to stand on to reject his invoice based on their contract terms? I am thinking of making a counter offer. What happens if I don’t pay his invoice?