Rental Home Depreciation is 40 years how to add improvements to its basis

When we started renting a home 8 years ago we chose 40 year depreciation.

This year we made improvements to that home (which has been a rental throughout).

     These are NOT items to deduct as maintenance or repair.

 

How to we indicate an increase in basis?

Do we just add a separate asset sheet and depreciate the improvement separately?

      If I add a new asset (the improvements) for depreciation can I choose 40 yr again (or must I use the 27.5 default)?

Or can I add to the original basis and continue the depreciation on the original sheet (for the remaining 32 years)?

 

As a numerical example:  Original Basis $200K (80K was land).

    Of the $120 Structure value we have depreciated $20K so far (so the remaining basis as of today is $180 with 32 years left remaining).

    This year I made $30K in improvements. Can I add it to my basis (increasing it to $210 - 80K still Land) and continue the depreciation? If so, where do I enter that increase (yes I have receipts for all the improvements).

 

Appreciate guidance