Yes, you can claim Capital Cost Allowance. This should be claimed when filing a Section 216 Non-Resident Rental Return.
If you converted your primary residence into a rental property, then the cost basis of your property is equal to the fair market value of the property at the time of conversion. Subtract the land value from the total value at the time of conversion to arrive at the value of the building. The building can be depreciated (land cannot). If you missed claiming depreciation in a particular year, then file an amended return for that year with the depreciation amount.