A Debt Consolidation Loan can be arranged in a number of ways.
Firstly, an unsecured personal loan direct from your bank or other lender.
Secondly, by remortgaging your property to release enough equity to pay off your outstanding debts this way.
Lastly, by securing a second charge mortgage against your property.
The first option of an unsecured loan is very unlikely where you have bad/poor credit and already defaulted on existing debts. There may be advantages to remortgaging over a second charge mortgage but generally, a second charge mortgage will allow a lower interest rate.
In all debt consolidation loan cases, where you do have debts that have escalated to incur additional charges and fees, you should consider requesting full and final settlement amounts from your creditors in writing.