Re-plumb: Expense or Depreciation?

[Steve Scherrer]

My rental condo is at a point where I need to replace the water supply lines in the unit.  The existing plumbing are the old polybutylene pipes that become brittle over time (30ish years) and are prone to developing leaks.  The cost to re-plumb the unit is about $4200.  The question is, would that kind of cost get depreciated, or is it possible to claim the entire amount as an expense?  The brand that gets installed would have a 25-year warranty, if that is relevant.  TIA.