Can anyone tell me how turbotax generates the "Base amount" (BA)of a new addition under CCA? I see cost, and then a base amount that is 1.5 X for BA?

[joanneknut]

I am trying to understand how the "Base Amount" is generated on a new addition. My class 8 addition for 2025 on a rental property, which is not eligible for AII nor ZEV was calculated at 1 and a half times the cost. As such it has generated a CCA which is more than 50% the rate for class 8, and I understand I am only entitled to claim 50% (of 20%) in the first year.

[TurboTax_Susan]

The base amount for CCA is the remaining UCC amount after additions, dispositions & current-year adjustments. It's column 12 + column 14 less column 15. 

Did you have anything else in class 8?