All house builders under the Consumer Code for Home Builders have requirement to inform you of all relevant information regarding your home before you buy it and this would include subsidence and work to fix major defects.
Ask your solicitor to get the house builder to confirm or otherwise. Assuming you haven't made the mistake of using a solicitor 'suggested' by the house builder!
I have asked you
twice to name the house builder and it is even more relevant to others now as you say that they will not allow your new home to be inspected by anyone before you have bought it, even though it is a completed ex-show/view home!
You should read this
Buying the Show HomeThis must send out warning signals to you! What is the house builder affraid of?
What do they think an inspection will reveal?
Whilst it is true that any inspection would not be able to reveal any foundation problems (including underpinning works) or any other such hidden defects it would at least list those that are visible now and probably causes and solutions.
Having defects fixed by a reluctant house builder after you have moved in is never a good situation.