Confirming how to hand depreciation for renting a portion of our home

Hi,

 

We are renting an Accessory Dwelliing Unit basement apartment that is approximately 30% of the square footage of our home. I understand that I need to prorate expenses such as utilities, insurance, and mortgage interest. 

 

Do I do the same for the depreciation- basis cost?  Do I adjust for the amount used by the apartment?  Thanks for any insight on how to handle the depreciation.