Toilet paper, like all paper, is made using a chemical engineering process. That means manufacturing is a continuous process that runs 24 hours per day, 7 days per week. Raw materials go in one end of the manufacturing pipeline and paper comes out the other. In between there is pulp, liquids, hot slurries and hot paper before rolls of paper come out the other end.

When I was a volunteer firefighter, we had a tour of a local paper mill so that we’d have some familiarity with their facility, in case an emergency occurred. At one end of the building, they took in materials such as recycled cardboard and paper, plus wood pulp.

Paper products went through a de-inking process and another process to break up the fibers. Wood pulp went through another process.

These materials were bleached (to make white paper) through vast vats of chemical processing. Eventually the materials were formed into a wet slurry that was gradually compressed into thin sheets and dried, then rolled on to giant spools.

The huge rolls of paper were then removed and went through a slicer to cut to the required lengths.

This process ran 24 hours per day, 7 days per week and was only stopped, rarely, in case of break downs or required maintenance. Unlike manufacturing of widgets with discrete parts, paper is a chemical process where the liquid parts flow continuously through the system.

To accommodate changes in market demand for their paper products, the entire system would be sped up or slowed down – but never stopped.

From my reading, toilet paper manufacturing is pretty much the same process. Since toilet paper consumption does not vary much, industry has built paper factories designed to meet the normal, on going demand. There is little buffer in the system except for toilet paper stored in warehouses, distribution centers and on store shelves. There does not need to be a lot of buffer because ordinarily, demand is near constant. And we’ve built factories to optimally meet ordinary demand.

The Covid-19 epidemic caught many people off guard. Undoubtedly, those who may have bought TP weekly or twice a month now bought larger packages. Very quickly, the entire distribution buffer was drained – inventory moved from the distribution network to homes.

Additionally, the government’s messaging on “Stocking up” was very confused, inconsistent, contradictory, unclear and generally ineffective. Initially, the government said no one should stock up.

But by the 3rd week of March, the CDC’s official recommendation was that older people and those with underlying conditions (which is 40% of the population, combined) should stock up on supplies and avoid contact with all people. Thus, in fact, much of the population absolutely should have stocked up. Consequently, blaming consumers for stocking up is wrong – many may have figured this out well before the government – those at higher risk did indeed have to stock up and many likely did stock up in advance.

TP continues to be made at the same speed it has always been made – in fact, one maker says they’ve been able to ramp up their factory to about 20% more per day. But with TP in short supply, many consumers will launch a second round of buying, purchasing any available toilet paper.

With a limited ability to ramp up production, it may take time to refill the buffer – warehouses, distribution centers and store shelves.

UPDATE: Here is a related explanation of the toilet paper shortage – not caused by hoarding but by shift from industrial/organization use to home usage as businesses shut down.

Short version – there are two markets for toilet paper – industrial/organization and consumer. They have mostly different products in each segment. Consumer products are soft, two-ply, packages in small numbers of rolls. Commercial products sold to industry, restaurants, schools tend to be coarser, sometimes single ply, often sold in large packages and very large roll sizes – completely different products than consumer products.

When everything shut down there was a surplus of non-consumer toilet paper in the industrial segment – just as everyone was now going poo at home. Consumer product purchases increased by +40%, emptying the distribution network. While there may have been some hoarding, it was mostly a shift from industrial usage to consumer usage that caused the shortage.

That also explains why we were able to purchase toilet paper from a restaurant supply/distribution warehouse while all the usual consumer stores were out of stock. This week, most stores are having toilet paper in stock again, or at least during the first few hours of the day!