When you take out a remortgage, (move your mortgage
from one lender to another but don't move house) your new loan pays off the
existing/outstanding mortgage any surplus monies applied for beyond that needed
to repay the original debt is deemed to be capital raising.
You can, depending on your lenders particular criteria, capital raise for many
purposes such as debt consolidation or home improvements but it is wise to
ensure that your lender allows the type of capital raising that you might
require before applying for your remortgage.