by Incredulum on Thu Aug 18, 2011 4:02 pm
I don't think there should be any risk there is a trade (unless you are a builder... and even then the 12 years' residence I think precludes that).
If you sell them then in my view you suffer a CGT liability on any gain that has arisen from the spending of money to split the property into two. The rest of the gain is exempt as you lived there.
e.g. You bought residence in 1998 for £10,000.
In 2010 it was worth £100,000 as a single dwelling.
Then you spent £30,000 in creating two flats now worth £75,000 each.
Capital gain = proceeds 150,000
less enchencement costs(30,000)
less value when converted (100,000)