I took out additional borrowing on our home in order to pay off more expensive buy to let there by replacing a 5pc mortgage with a 2.5pc (tracker). I have now spoken to the Inland Revenue 4 times about this just to check that I can still offset the mortgage interest avaunt the rental income. Just thought that I would share this with you. I mentioned this before and an officious poster gave me real grief. I am now confident of the tax position but you can always call the self assessment line of HMRC and ask ...they will arrange for you to speak to a technical expert.