here are safe harbor discussion
Safe Harbor for Routine Maintenance
You are not required to capitalize as an improvement, and therefore may deduct, amounts that meet all of the following criteria:
Amounts paid for recurring activities that you expect to perform;
As a result of your use of the property in your trade or business;
To keep the property in its ordinarily efficient operating condition; and
You reasonably expect, at the time the property is placed in service, to perform the activities:
For building structures and building systems, more than once during the 10-year period beginning when placed in service, or
For property other than buildings, more than once during the class life of the unit of property.
If the amount doesn't meet all of the requirements for the routine maintenance safe harbor, you may still deduct the amount if the amount is not for an improvement under the facts and circumstances analysis.
For more information about class life, refer to Appendix B of Publication 946 which includes class life, recovery periods, and a glossary of terms.
What are the most important exceptions from and inclusions in the routine maintenance safe harbor?
The routine maintenance safe harbor doesn't apply to amounts paid for betterments.
The routine maintenance safe harbor does apply to certain restorations that would otherwise be improvements, including when you pay amounts to replace a major component or substantial structural part of a unit of property.
