Originally Posted by RAT8OY

I am a senior building surveyor and you should really seek the advice of the local planning department. There are many many issues you will need to address despite what people will tell you. Nothing to worry about but get some formal advice in writing to cover you!

I do not wish to sound like an arse but asking a question like this is a bit like saying how do I build a cosworth engine with no previous experience. Its not hard as long as you know! Potentially very very costly if you dont!

Good luck anyway and go for it, take it as a challenge and you will learn a lot!