Is foundation work on a rental considered improvement or repair?

[ah]

Pier and beam house with essentially no clearance in crawl space so foundation was lifted and leveled at the same time.

[ColeenD3]

That is definitely an improvement. It has a useful life of 27.5 years, the same as the building.

[ah]

To follow up, because the foundation was lifted and some beams replaced, it broke some plumbing, porch posts, siding, drywall, etc. Would this additional repair work be counted as improvement or repair. 

[ColeenD3]

By itself, it would have been a repair, but when done in conjunction with an improvement, it becomes part of the improvement.