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# Cob speed

In the early Eighties I read a very interesting little book by a philosopher named Ivan Illich. The book was about driving cars and started out by calculating the average speed at which a car travels in its lifetime. Want to guess? The answer is 6 miles per hour. This is true because you can’t measure the speed on the speedometer alone; you have to take the annual amount of functional miles you drive and then divide that by the total time you spend in your car (including traffic jams), the time you spend taking care of your car (washing, bringing it to the shop), waiting at the shop, getting gas, changing the oil, changing a flat, buying and selling the car, dealing with an accident, and, often overlooked, you also have to count the time you spend working so that you can afford the car (as well as the insurance, maintenance, and gas). How about working to pay taxes to build roads? Make a reasonable calculation of all this and you come to an average speed of about 6 miles per hour. That is pretty low considering the high cost of cars to our society: 42,000 deaths per year by fatal crashes, more than a million people injured, endless paving of the natural world, global warming, etc. Using the same calculation, a bicycle will get a significantly higher average speed.

One concern that comes up a lot during our workshops is about the speed of cob, or rather its slowness. The argument goes something like this: 2 different groups want to build a 1000 square foot house. One group is a bunch of strong males in their twenties, armed with tool-belts and power tools, and with a huge pile of lumber, concrete and drywall at their disposal. The other group consists of a bunch of barefoot hippies with a few shovels, mixing tarps, buckets, and a machete. If the design of each building is the same, which building will go up faster?

Of course the answer is that, under these circumstances, the conventional method of building will go up many times faster than the so called “hippie-cob building” method. Following this line of thinking, many people admit that cob buildings are beautiful, healthy, less expensive, more sustainable, magical and what not, but that they just don’t have the time to build one: it could take 2 or 3 building seasons to build a cob house for a family, while a conventional building can have a

key in the front door in a matter of 6 months.

Yet if we consider the “Real” speed of these two methods, just like looking at the real speed of a car, cob building will win HANDS DOWN!

Before we make that comparison, we should briefly ask ourselves how useful “speed” actually is. If I really enjoy what I am doing (building with cob), would I want time to go faster? Is the earth longing for more efficient and speedier building methods so that we can build more houses in less time? How about the forests around me, the animals, the salmon? There are 30 million homes standing empty in the USA. How many new homes do we need? What goes up fast comes down fast: The average house in the USA lasts about 30 years. When evaluating the usefulness of speed, we need to consider how speed affects the quality of our houses.

Let’s get back to comparing the speed of cob building with the speed of conventional building. First we need to make the contest fair. As cob builders harvest some and produce most of their own building materials (digging up clay soil, mixing it on a tarp by foot), we should expect the conventional builder to do the same, or we should at least calculate the work that the lumberjacks, truckers, sawmills, truckers again, lumberyard, and truckers again, do to get the wood over to the building site. Similar calculation can be made for concrete and drywall. In other words, one of the reasons why conventional construction seems faster is because a lot of work has already been done before we start actually building. That is just not fair!

Although I won’t need this argument to prove my point, it is worth mentioning that it takes a lot more time to heal an acre of clear-cut forest than a small hole in the ground near the building site. I also won’t calculate the wars we have to fight to gain control over oil so that we can mine, produce and ship all these building materials. Concrete in particular is extremely dependent on very high-energy inputs (10% of all CO2 produced in the world is related to the production and transportation of concrete). To be fair, the materials used in cob also have an environmental impact: straw bales and sand is often delivered from distant locations and produced by industrial processes. These materials cause only a fraction of the destruction that lumber and concrete cause, but they should not be considered truly “sustainable.”

Then there is the power-tool issue. Again, I will not calculate the cost and time and cost related to the infrastructure of oil and the power-grid, but, give a group of well trained cobbers an unlimited amount of tools, electricity and diesel fuel, and they will be just as speedy, if not speedier, than the conventional builders. Tractors, mortar mixers, bobcats, plastering guns, and other tools can make things go really fast. Of course there is a cost to this speed: one of the reasons cob houses last so long is because they were hand-built and therefore instill the owner with a strong desire to care for the house. Many conventional houses in the USA don’t last long not due to structural failures but due to the fact that nobody cares about them: at some point it may become more profitable to bulldoze them down then fix them up.

So how should we calculate the “Real” speed of building? If I spend 5 years building a cob house that will last 500 years, or 6 months building a conventional house that will last 50 years, the relation between the time spent building and the longevity of the house is about the same for each method (for a year of building, you get 100 years of house). That in and of itself would equalize the speed contest.

Then we have to talk about the size of the houses. Conventional houses tend to be “box like” with an enormous amount of space being wasted on hallways, high ceilings, attics, space behind the couches, etc. Poor, wasteful design is often caused by the standardized building materials: A 4×8 sheet of plywood has nothing to do with how we work, move, or live as human beings, but rather is produced for ease of transportation and building. Hand-built cob houses tend to use space very efficiently, and will feel as spacious as a conventional house that is about 30% larger. I live in a house with a cob interior and I often ask people to estimate the square footage of my house, right as they walk in. They look around for a while and then hardly ever come up with a number lower then 1400 square ft, even though my house is only 970 square ft.

And lifting those 4×8 sheets of plywood will cause problems for most people. Go by any building site and check out the ages of the framers, dry-wallers, and other workers. Most of them are under 40. Where are the old dudes? They are doing different things and a lot of them spend part of their time dealing with back and joint injuries. You can honestly do “hippie cob building” from the ages of 8-80 and it will likely improve your health. So we should count the weekly trip to the chiropractor as lost time, as well as the cost for pain medication. The initial speeding up (during construction) often leads to a significant slowing down later on. And then I have not yet mentioned all the other injuries related to speed and power-tools. Let’s just say that you miss with the nail-gun and end up with a framing nail in your body. That can easily take you out for a couple of weeks. I have now taught cob for over 10 years to novice builders and the worst injury during my workshops was a laceration on the wrist, caused by someone opening a bottle of wine with a poorly designed wine bottle opener.

Conventional buildings can be much more expensive then “hippie-built” cob buildings. Where does that money come from? Well, early on, the conventional builder had to sell his or her time to get the money to build the house. Do we count that? I think we should. What if you have to take out a mortgage and you have to pay twice the amount over the 30 years that you are making payments? What if your house is not as efficient as the cob house and you also have to pay for more heating and cooling?

There are more “less tangible” reasons why cob building is so much faster than conventional building. For example, because it is so safe and simple to learn, it is much easier to get your family, friends and community involved in the project. But by now, I think most of you have concluded that cob building is much faster than conventional building. Based on my experience in both methods, I would say that “hippie cob building” is between 4 and 8 times faster than conventional building. Hmmm… Can we still call it “hippie building?”

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