Old alterations without planning - Problems now selling?

I have got myself into a pickle and now need advice. Apologies if this gets a bit long winded. We are in the process of selling our house. We bought it in 1995 and it had already had extentions and a wall knocked through for which planning had been obtained. The year after we moved in we made alterations ourselves for which planning wasn't sought. The alterations we made were to replace a wall that had been removed and remove a different wall, remove a chimney breast and remove an upstairs w.c and partition wall. I should say at this point that it was all done by a qualified tradesman. I have filled in a solicitors questionaire and said the alterations were already done when we bought it (I did this because I was scared of what would happen as we hadn't had planning permission). I regret doing this and now have been asked by the solicitors for any documentation I may have relating to works before we moved in. Before this goes any further I'm hoping to put things right but have no idea of the consequences. What happens when I come clean?(no idea what I'd say at this point) and if I didn't, would I be committing a serious offence? And will the solicitors be able to see from past planning applications that the internal layout is different from when we moved in?
I'm very worried about all this now, I know what not to do in the future but dont know how to handle this now.

Get and Architect/ Engineer. Go through all the various works done on the house. Get all the paperwork you have - with deeds. Ask Arch/Eng to look at it all and confirm what needed pp and what did not. If did, there needs to be pp plus Opinion on Compliance. If not sought, should you seek retention permission or seek to limit contractual position in your sale contract. If not needed, is there an opinion on compliance with anything necessary and similar with Building Regs?

Tell Solicitor now that you had misunderstood situation , that there have been changes and alterations and that you are taking advices on what is what. Solr. needs to know so that can draft Contract correctly. If he does not know, it is your Contract that you are signing and it will cause untold problems.

It is not insurmountable but needs to be addressed.

mf

From your description I get the impression that these are internal alterations only. (i.e. no windows broken out, no extension etc. If this is the case, there is no impact on Planning and no Permission required.

Removing the chimney breast might mean taking down the chimney though - which probably requires permission (depending on location).

As long as contracts have not been issued you are not misrepresenting the situation. as the previous poster stated if they are internal then pp is not an issue but getting an engineer to check it out is a safe bet, if the parties get the property surveyed then an engineer/surveyor will spot that works have been done. you would be surprised what items can be exempt but get a letter from your engineer confirming it is exempt, as previous said if not then you have to apply for retention unless they are done in excess of 5 years ago where an amnesty exists. If pp is required and you do not have it then the purchasers would have to detail that to their bank so you would be forced to sort the issue. the amnesty only means that the council cannot force you to rectify it it doesn't mean it becomes authorised. just explain it all to your solicitor and it'll get sorted.

Thanks all for your advice so far. It doesn't sound quite as bad as I first thought. Hopefully I can now get back on the right track!