The $25k must be depreciated as it is an improvement. The recovery period is 27.5 years.
How Do You Treat Repairs and
Improvements?
If you improve depreciable property, you must treat the
improvement as separate depreciable property. Improvement
means an addition to or partial replacement of property
that is a betterment to the property, restores the property,
or adapts it to a new or different use. See section
1.263(a)-3 of the regulations.
You generally deduct the cost of repairing business
property in the same way as any other business expense.
However, if the cost is for a betterment to the property, to
restore the property, or to adapt the property to a new or
different use, you must treat it as an improvement and depreciate
it.
Example. You repair a small section on one corner of
the roof of a rental house. You deduct the cost of the repair
as a rental expense. However, if you completely replace
the roof, the new roof is an improvement because it
is a restoration of the building. You depreciate the cost of
the new roof.
The painting can be added to the improvement if it directly tied in to chimney repair or if unrelated can be an expense.
https://www.irs.gov/pub/irs-pdf/p946.pdf
https://www.irs.gov/publications/p527
