The shell defaults to 39 years, but 20 to 40 percent of a building’s cost often belongs in 5, 7, or 15. Feasibility comes first, in writing, before you commission anything.
Same electrical run: general lighting = 39 years. Dedicated process equipment = 5 years. We document which is which, from drawings, invoices, and the engineering analysis of your facility.
| Component | Serving the building | Serving the work process |
|---|---|---|
| Electrical distribution | General service & outlets 39-yr | Dedicated circuits to workstations & equipment 5/7-yr |
| Lighting | General illumination 39-yr | Task & inspection lighting specified to the process 5/7-yr |
| Data & low-voltage cabling | Building systems wiring 39-yr | Cabling serving process equipment & operator stations 5-yr |
| HVAC | Occupant comfort 39-yr | Zone conditioning required by equipment or process allocable |
| Partitions & finishes | Structural walls 39-yr | Modular partitions and process-driven millwork 5/7-yr |
| Site improvements | Parking, walkways, landscaping 15-yr |
Illustrative only. Nothing here is a promise for your building. Classification follows the engineering analysis of your facility and current IRS guidance.
You built, bought, or substantially renovated commercial or rental property in recent years, or you're about to.
The building serves a process: production, food service, medical, logistics, a lab. Not just desks and drywall.
Construction-in-progress or a purchase is sitting on the balance sheet depreciating at a flat 39 years.
You missed it in a prior year. Lookbacks can often capture the difference without amending, when the rules allow.
Send the property basics: cost, type, placed-in-service date. You get a written "worth it or not" before commissioning anything.The off-ramp is free to take
Each allocation tied to function: what the circuit, duct, or partition actually serves. Drawings and invoices are the evidence.
Asset-by-asset allocation with functional-use evidence, ready for your preparer.
File it. Lookbacks when allowed. Your preparer or ours.
Send the property basics (cost, type, placed-in-service date) and we'll tell you in writing whether a study is worth commissioning.
Request a Feasibility Review