Not sure what you mean. Are you proposing to lock in part of your mortgage that currently is floating? If so - slow down. That will not create a tax deducible loan. The loan you have now is not tax deductible or tax effective. What you must do is repay the loan - that was raised to buy your home and is not deductible. Then after repaying you can organise a new loan to invest, and that will be a tax effective loan as long as it is borrowed with the intention of furthering your income through investing. Timing is crucial.
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