If your carry forward your information in TurboTax, the Undepreciated Capital Cost (UCC) amounts are going to reflect the 50%.
Assuming you are claiming Class 1 CCA , there is no need to adjust the UCC amounts that have carried forward, instead you will need to claim a Deemed Disposition of 50% of the Rental Portion of the house.
- Assuming the house has not appreciated in value tremendously, a fairly accurate way to do this would be claiming 50% of the starting cost you entered in Class 1 as the Deemed Disposition.
- If the house has appreciated in value since the time you started claiming Class 1 CCA, you should determine the Fair Market Value (FMV) of the entire house and claim 25% as the Deemed disposition.
Here's some more information on disposing of property you might find helpful: TurboTax Tips