This is something I need to look into. I don't live at the house I own, but my driving licence (and car) are registered there (in fact the car is parked there right now - I hope!). I'm not sure whether that's OK or not, and to further complicate the issue, I don't actually reside in the UK, so I don't know if I need to change my driving licence to an Irish one, and what the implications of that are.
I have a similar problem, except I don't own a house at all. My registered address is still my parents house. As long as you respond to the mail that gets sent there then you count as living there.