A Home Kanban System – Toilet Paper & Paper Towels
Here is a recent post from my blog at the Institute of Industrial Engineers site:
In the course of my consulting work, I'm sometimes asked something like, “OK, so do you use this stuff at home? Do you 5S your kitchen and your garage?”
Well sure, I've “5S-ed” my kitchen, in the sense that I try to keep items and equipment in the right locations. Last year, we moved the storage location for our knives so it was right in the island where we usually chop (and right near where we grab the cutting boards). So if you consider that 5S, sure we've used some elements of the approach. Do we have tape around everything? No, of course not.
The closest thing we have to a formal Lean system is our use of “kanban” to manage some home inventory items. Two items that are managed via kanban are toilet paper and paper towels.
In the garage (the “bulk warehouse”) sit two large warehouse club sized packs of toilet paper and two packs of paper towel. This is a very simple system — when one warehouse club pack is empty, that's our signal that we have to buy more. The beauty of the “two-bin” system is that we still have a whole pack left (plus what is in the house). We don't have to interrupt our lives to go to the warehouse club “NOW.” We can wait a week (or even two) and have it on our list to buy when it's convenient.
This kanban system prevents overordering and it helps us avoid running out. Notice that no math went into this kanban system. We're often so focused in the Lean world on “getting the calculation right” instead of just having a system that works. Since toilet paper and paper towels are cheap enough, we really aren't worried about the cash tied up in the inventory. These products don't expire, although we do rotate our stock and use the oldest stuff first. If we lived in a small apartment, instead of a suburban home, we might have to set this system up differently. Post continues below the ad.
There's a second kanban loop (or loops) for each item – from the garage to the points of use. For paper towels, these are stocked in the kitchen. Here, when a roll is empty, we just get more from the garage. No “two-bin” system, just a simple “need one, get one” replenishment.
For toilet paper, we do keep some inventory in each bathroom. I'll try to keep this discussion polite, but we really want to avoid a total “stockout” in a particular bathroom. So there, we tend to keep a six-pack of rolls in the bathroom. When the last roll is placed on the holder, that's the signal to get more from the garage “now” instead of waiting for an, ahem, emergency situation.
In the couple of years that my wife and I have been managing our inventory this way, we've avoided emergency trips to the store or emergency trips to bring more rolls to a bathroom. The value of that far outweighs the cost of $20 of inventory in the garage.
I've also applied a simple two-bin system to many of my items like shampoo, hair gel, shaving cream, etc. I always keep two on hand — when one is empty, I always have a spare ready to use and I can buy a replacement at my convenience.
Does anyone else run their “home inventory” this way? Same thing could apply to kitchen items and food, don't you think?
I like our kanban system because:
- It works
- It's simple
- It didn't require math
- It didn't require a computer system
Don't you think those same principles could apply to many items in our workplace?