The redux of my question from last Friday with the answers filled in:

In a meeting with a new client, we were discussing possibilities for shifting things around in his factory (he wants to expand). I made what seemed to be the most obvious suggestions but I was puzzled that he didn’t already know because he’s been a garmento for 25 years. Client said, “my building isn’t a rectangle, it’s a square”. My companion and I said “oh”… because there was nothing else to say. Why does building shape matter? What shape should a factory be?

Recapping, the client’s building is not a rectangle, it’s a square. If you have limited square footage, the shape matters. You know how I always say that inches aren’t created equal? That goes double for square footage.

We didn’t have many comments but they were all good for discussion. Alison was first and mentioned that rectangles are optimal. Ideally though, inputs (receiving) and outputs (shipping) are processed in the same place because one would (in a perfect world) have an overhead door with an area trucks could back into.

Both Alison and Gail mentioned squares or square donuts. This wouldn’t be a bad shape (upper right) but it wouldn’t be as efficient. Arrows indicate work piece flow -not to be confused with worker flow. For example, patterns should be dead center to interface with related production departments (where design is) but design needs to be next to patterns and admin (includes sales). The big draw back to this plan is that admin and design need a separate entrance to receive clients and general business. Other than image (if it matters to you), the back dock area is a safety zone meaning visitors and office people must be properly attired and they usually are not.

A U-shaped work space of the same square footage is even less efficient. Admin has its own entrance (right) but it comes at the expense of less work area for production. Also, we now have two shipping and receiving areas to traipse through.

Paul brings up several excellent points which (I think) are self explanatory:

Shape may not make as much difference as ‘aspect ratio’ (length to width) relative to the limiting width and length of various process elements. Sometimes you can add 6 feet to the width or length, but it does you no good at all because your process grows in 20 foot increments.

My guess is that the building is L shaped rather than rectangular, and I recall Kathleen saying that an efficient cutting table is at least 100 feet long. Or on more than one floor, or in two or more buildings? The key is to limit unnecessary handling and movement of materials, regardless of building shape. Each step in the process (material receiving, raw goods storage, on through final finishing/packaging and shipping) would have its finish point adjacent to the start point of the next process. Since shipping and receiving are both at the dock, the whole process ends where it starts.

[I don’t think I ever said a 100 foot table is the most efficient but a small contractor should have at least one 24-32 foot table; they are not a contractor if they only have one table that is only 8-12 feet long!)

Marie-Christine says if shape is so important, then one should plan for it at the outset. This is optimal but as Paul also said, companies add segments or functions over time, taking on the next available empty space rather than re-arranging. Re-arranging is disruptive and costly so it’s often a case of minimizing flow disruptions. The point being, you may need something very different as you grow and your goals change. The client in my example started retailing from this space so a square wasn’t bad. He had another plant location but he let it go when he and his wife cut back so they could focus on raising their family.

One thing that wasn’t mentioned in comments was plant infrastructure, the location of utilities, outlets (power requirements) and lighting. For smaller businesses, it may not be possible to reconfigure these elements either because one is leasing or the cost of moving them. It’s one thing if it’s your own space. You can come up with a central plan and list what’s in place vs what you have to budget for down the line. Again, the client in my example has three phase power -a feather in anyone’s cap- and I would be just as reluctant as he is to let it go. I also suspect he owns the building and would have to come up with a lot more money to get into another building. Again, I would be just as reluctant to do that before he has demonstratives of expansion in the pipeline.

Tomorrow I’ll show you a layout of my shop. It’s of optimal shape with some amenities but it has downsides too -reminding me of the literal meaning of the poem “The best-laid plans of mice and men/ Go oft awry” because I’m going to be a nervous wreck until fledging season is over.

Related:
Plant organization
Plant organization pt.2
Plant organization pt.3
Commercial vs Industrial space