We are in the process of putting our house on the market & had an EA round this week for a valuation. When we bought the house (7yrs ago) the previous owners had extended the kitchen & done a loft conversion. Whilst I was showing the EA round he said something like "obviously you've got all the building regs for this?" - I just kind of nodded & intimated that we did.
However I have no idea if we do - I'm presuming our solicitors would have let me know if there weren't the appropriate building regs when we bought it (the Managing Partner is a family friend & we know the firm well). If we do have them, where will they be & how do I check? 
Sorry if this is a very stupid & naive question 