What does your spare-parts storeroom really cost?
A storeroom costs you twice: the carrying cost of every part you hold, and the downtime cost of the critical part you did not. Most plants pay both at once, overstocked on slow movers and short on the spare that stops the line. Enter your numbers and see the real annual total. Numbers update as you type.
Your storeroom
Use your total MRO inventory value and the critical stockouts that actually stopped production.
Carrying vs stockout
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Put a real number on the parts you wait for.
The stockout side of this cost is invisible until you log it. The free OEE Tracker captures every stop and its reason, so waiting-for-a-part downtime stops disappearing into general breakdown time and shows up where you can act on it.
Open the free OEE TrackerStock the parts that stop the line, not the ones that sit.
Fabrico links each spare to its machine and alerts you when stock falls below the minimum you set. Less capital on the floor, and fewer lines down waiting for a part that should have been there.
Book a Fabrico demoThe storeroom is a hidden cost centre
Spare parts feel like insurance, so they rarely get challenged. But every part on the shelf ties up capital, takes space, and can go obsolete before it is used, and the parts you skipped to save money are the ones that leave a line down for a shift. The two costs pull in opposite directions, which is why cutting inventory blindly raises stockout risk, and stocking everything blows the carrying cost. The goal is not less stock or more stock, it is the right stock.
The math
Carrying cost = inventory value times the annual carrying rate. Stockout cost = critical stockouts per year times hours waiting per stockout times downtime cost per hour. Total storeroom cost = carrying cost plus stockout cost. The stockout share tells you which way your storeroom is out of balance.
The parts most worth stocking are the ones that stop a machine and take long to source. The guides for the mechanical seal, solenoid valve, sensor and photo-eye and coupling help show which failures to stock for. For the full method, see spare parts management.
What carrying rate should I use?
Use the rate your finance team applies; it covers capital, storage, insurance, obsolescence and shrinkage. We found no published rate with a stated method, so the 22 percent filled in here is only a starting value to change.
How do I know my critical stockouts?
Count the times in the last year a job waited on a part that was not in stock and a line or asset was down for it. If you do not track it, that is the first fix, and the free OEE Tracker captures the reason on every stop.
How do we right-size the storeroom?
Set min and max levels from each part's link to asset criticality, not from habit. Protect the spares for critical bottleneck assets, and let the slow-moving just-in-case stock fall. The CMMS ROI calculator shows the payback, and Fabrico is how it gets managed.
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