Cob Building Tutorial

Chapter 15: Us vs. the “Experts”

One of the side-effects of the Industrial Revolution is the over-reliance on ‘experts’ for every facet of life. Prior to the Industrial Revolution, farmers had to be their own ‘experts’ on everything from blacksmithing to veterinarian sciences to gardening to carpentry. Back then it was a matter of necessity, but these days it’s a matter of choice.

It’s nice to be able to pick up the phone and call an auto mechanic rather than to try to figure out how to repair an engine by yourself, but I think we’ve sacrificed a bit too much freedom in our over-reliance on the experts. If you’ve read this book, you can see that cob building is fairly easy. Almost anyone can do it. Yet many people balk at the idea that they can build their own home and grow their own food, and possibly even generate their own electricity. I think that’s a sad commentary on the times in which we live.  The industrial complex in which we live has convinced us through mass media outlets that we’re incapable of doing things for ourselves, so we must call in the ‘experts’ instead.

Let’s take the current mortgage crisis as an example. Most people in the United States, as of this writing, are having moderate to extreme difficulty in obtaining a mortgage for a new home. As the economy continues its downturn, such financing will become increasingly difficult to obtain. Consider that even if you are able to get a mortgage for a new home, you’ve just saddled yourself with a thirty-year commitment.

Now let’s look at building a cob home with materials obtained right on the property. Granted, building with cob is a labor-intensive process. It takes a lot of sweat-equity to get to the point where a cob home is livable. How long can it take? Well, I once read a story about a 71-year-old single grandmother in Canada who took a year to build an 800-square-foot home by herself. If you have more hands than just your own to rely on, it’s quite possible to build a home in less time, but let’s just say it’ll take a year to build your home.

During that year, I’m assuming that you’ll have some income coming in with which to buy building materials, but most of the materials will be harvested from your site. Let’s say you have an acre that’s half open field and half trees. The clay, sand and straw harvested from your site will go towards making the walls, and if you choose an adobe floor, the clay, sand and straw will go towards making the floor as well. You’ll need stones for the foundation, and gravel in the bottom of the foundation trench to assist in drainage. A truckload of gravel is about $25-$50, depending on your location. You’ll need about three truckloads for the average 1000-square-foot home. If you can’t find enough stones on your property for the foundation, there are still several options. You could go to building sites and harvest broken bricks and blocks for later use in your foundation wall. Or you could do as I occasionally do, and when you’re out on a drive in the country, stop and pick up any interesting rocks you may find on the side of the road. A third option, if there is a granite or rock quarry near you, is to ask what they do with their quarry rubble. Quarry rubble is the smaller stones left over from cutting out tombstones, granite slabs, etc. for commercial use. Most yards will give this to you for free if you have a way to haul it off. You could also check with excavating companies or in-ground pool companies to see what they do with the rocks they dig up. Failing all these other options, you could always purchase enough rocks to do the job, but since it’s much easier to find rocks for free, I’m going to assume you’ve done your homework and have managed to find a ready supply of free foundation stones.

Boards for shelving, alcoves, doorframes and windows can be readily obtained as well from a building site. Most contractors burn leftover boards in a barrel anyway, so talk to a local contractor and ask if you can have his leftovers. If you’re too shy to talk to a contractor, and can’t find a source of wood anywhere else, you can usually buy enough wood for a 1000 square-foot house (not including the roof) for around $200.

Some doors for your home (especially interior doors) can be built yourself if you’re fairly handy with materials. One effect I especially like is crosscutting logs, and then nailing them to a plywood backing in diagonal patterns. If you lack skills at carpentry, you can also get by without interior doors by strategic use of curtains and door openings. If you’d like to use curtains instead of doors, but would still like privacy, you can arrange room entrances so that there is a wall or partition blocking views into one room from another.

But let’s assume that you’ll not want to be making your own doors. Instead, you’re going to buy the doors from a salvage building supply outlet. In such a case, exterior doors will run you about $100 each and interior doors will cost about $50 each. Let’s assume five doors altogether: two exterior doors and three interior doors, for a total cost of $350.

Now we’ll turn to windows. Some of your windows, especially in alcoves, can be salvaged glass bottles or glass bowls. Since you can pick these up for free or for less than a dollar at a thrift store, there’s no need to count these in the cost of the home. There are two more methods of adding windows. One is to install framed windows that can be opened. The other is to simply embed plate glass into the cob wall. In the latter method, you can get plate glass new for around a dollar a square foot. Salvage glass is considerably cheaper, but let’s figure on new glass for now. The average window in a home is about 5 square feet. This means that enough plate glass for such a window would be around $5. Let’s assume you’re going to have six windows like this in your home. That’ll cost you $30.

Next, you’ll want some framed windows to allow in breezes. You can get these from a salvage yard, or you can make them yourself if you’re handy at carpentry. In either case, they’ll run you around $50each. Let’s be generous and assume you’ll have six of these in your home too. That’ll be $300.

Now, let’s look at plumbing fixtures. You’ll need a toilet (unless you’re building your own composting toilet). A salvage toilet will run about $100. You’ll also need a kitchen sink and a bathroom sink. Figure $100 each for those sinks.

You can buy a salvage bathtub, or you can install your own shower by making it of cob and then tiling it up. In either case, you should be able to have a place to take a bath for around $100.

What about plumbing and wiring? Let’s allow $1000 each for these jobs. You can save more if you do it yourself (assuming your building inspector will allow it). You can especially save on the electrical work if you simply go without electricity altogether, but let’s figure on $2000 for plumbing and electricity.

The final cost to consider in order to be ready to move in is the roofing (this is assuming you’re making an adobe floor out of materials from the site).

I’m assuming here that for your 1000-square-foot home you’ll be using a green roof like the one mentioned in the chapter on roofing. I’m also assuming that you will have enough trees on the property to harvest enough lumber to make the support beams/rafters on-site. You’ll need at least a two-foot overhang all the way around the perimeter to keep the walls dry. This means that you’ll need somewhere between 1200-1400 sq. ft. of plywood roofing (depending on the pitch of your roof) for a 1000-sq. ft. home. This is about 40-45 sheets of OSB plyboard. At about $10 each, the OSB will cost you   

Next you’ll need enough plastic sheeting and adhesive to make your roof watertight. That’s about $50. Finally, you’ll need enough dirt (topsoil) to cover the roof to a depth of six inches. This comes free from the site. You’ll need to sod this soil with some sort of grass seed…preferably a local variety. If you’re going to do this yourself, figure on about $20 worth.

Let’s add a little extra cash for miscellaneous expenses…say $1125 to make our total a nice round figure of $5000 (for a breakdown of everything listed here, see the table below).

Note that this figure does not include the cost of the land itself, or building permits, or septic and water hookups, but includes most of the costs of actually building your home.

The point of this exercise is to demonstrate the cost of a cob home vs. the cost of a traditional mortgage on a stick-built home. If you go to a bank and attempt to finance the average home, which costs around $150,000, they’re going to ask for at least 5% down-payment. In many cases, they’ll ask for 10% down. Five percent of $150,000 is $7500. So if instead of investing $7500 as a down-payment on a house with a thirty year mortgage, you took $5000 of that down-payment and put it into materials for a cob home, and put the other $2500 into a down-payment on an acre of land, you could then have a home that was paid for when you finished it!

Granted, it might take you a year to build such a home, but is it worth a year of manual labor out of your life to avoid a thirty-year commitment to a mortgage? Consider the added advantage that while you’d need all of your down-payment up front for a traditional mortgage, if you’re building a cob home all you need up-front is the down-payment for the land itself. For the rest, you can purchase the materials as you need them over the year or so it’ll take you to build your home. In the end, you’ll own your home free and clear once it’s built, except for the payment on the land. Since you won’t have a huge mortgage payment to make, you’ll be able to pay off the land that much faster!

Chapter 1	Chapter 8	Chapter 15
Chapter 2	Chapter 9	Chapter 16
Chapter 3	Chapter 10	Chapter 17
Chapter 4	Chapter 11	Appendix A
Chapter 5	Chapter 12	Appendix B
Chapter 6	Chapter 13	Appendix C
Chapter 7	Chapter 14	Appendix D

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