When designing my cob house, it was a goal to keep building costs very low and to obtain as many building materials as locally as possible, especially natural (of course) and reclaimed supplies. Few materials were purchased new, and about as few are synthetic.
In this very detailed entry, Recipe for Building a Cob House, you can learn what it took to build my cob house for about $3000. You’ll also learn exactly how much cob I made (all by foot!), and specific amounts of material that went into the construction.
Please read ahead if you have any interest in building with cob!
Building time length
I started digging a foundation on April 19, 2008, and moved into GOBCOBATRON on July 11, 2009. I effectively worked from April to November of 2008, and then April to June of this year. In total, I estimate that I spent nine months working on my house, full time. I spent every possible day that I could working on my house, except for when it was raining (which was actually very often in 2008), and except when I was traveling. I literally worked practically every day per week full time.
Batches of cob
I stomped 219 batches of cob* for the walls of my house by foot, with the help of over 75 work exchangers, visitors, and friends throughout the year. The cob bed and bench took nearly 20 more batches of cob, almost 1/10 of the material it took to build the house itself!
*one batch of cob is equal to three 5 gallon buckets of sand, and 2.5 worth of clay, nearly 30 gallons of material.
Cost of my cob house
I have kept close records of the costs of my building materials, and have determined that I have spent less than $3000 on building materials for my cob house. (I spent another $1000 on labor.) Here’s what I actually bought, and what I paid for my building supplies:
- sand (just over 30 tons total) – $507
- gravel (about 13 tons total) – $177
- straw (16 bales) – $36 (most straw I used was free)
- black walnut scrap lumber – $100
- misc. lumber – $20
- windows – $220 (two casement, one double hung window)
- electrical – $28
- galvanized wire – $30
- nails – $100 (I couldn’t believe how expensive nails are)
- raw linseed oil (for floor) – $72
- EPDM pond liner $622
- polycarbonate for skylight $400
and for the rocket stove:
- firebricks – $70
- flue pipe – $228
The two most expensive individual items are in bold. (Perhaps not surprising is that they are both part of the roof.) As you might imagine, many things are not listed because they were obtained for free – clay for cob, roof rafters, (hand harvested from our land and neighbor’s land), my large south window, urbanite for the foundation, etc. This is a very inexpensive house.
The total cost of supplies for my cob house is $3000. If figuring in labor costs, the house cost $4000.
Recipe for building a cob house
With $3000 for supplies and nine months of full time labor, I was able to build GOBCOBATRON, a small cob house with interior dimensions of roughly 15′x13′, and a footprint of (again, roughly) 20′x18′. Practically all of the labor was completed by hand (and foot!), including making and applying all of the cob.
It’s true… you can build your own cob house with little money, but with lots of time and enthusiasm. Extra hands never hurt, either! I can easily say that my Year of Mud was the most satisfying experience in my life. There’s nothing quite like the experience of building your own home with little more than your hands.
For complete photos of the construction of GOBCOBATRON, vist my photo album here.
[...] houses I’ve found online are absolutely beautiful! (Check out my favourites here, here, and [...]
Wow… we won’t be able to do much of our work ourselves…but this is a great house inspiration. Thanks!
Looks great, but I wonder where the bathroom is? Can’t see any costs for loo or shower/bath, or any indication that it is plumbed at all, even for rainwater usage. I understand that it is possible to live without these or to use compost loos etc, but most people would assume they’d be costed into the calculations for something described as a “house” rather than a “shed”?
You say the cost of the house, with labor is $4,000.00. Either labor in your area is worth next to nothing ($1,000 for nine months of work), or you’ve left out a zero.
There is no bathroom. I share common bathroom facilities with others in another building. That is important to note, yes… thanks for calling that out.
Tom: I hosted a number of “work exchangers” last year — people who came to Dancing Rabbit to help me build and gain cob experience in exchange for their cost of living while they were here. It is very inexpensive to host a work exchanger here: the biggest expense is food, which was $180/month for me at the time. Effectively, they were unpaid and worked in exchange for the experience. Now you can see why labor was so cheap! I typically had at least one work exchanger at a time throughout last year.
ziggy – congratulations on a beautiful home. i enjoy learning about people that are passionate about creating unusual dwellings. i want to know how your house does in heavy rain. you mentioned it rained a lot during building. i live in a tropical location where we get heavy rain part of the year and sometimes heavy winds and tropical storms and want to know if you think a cob house is practical in this environment. thanks.
What will the upkeep entail for the house and what is the life expectancy? I looked through all your photos and didn’t see much in the way of electrical. It looked like there was one box there. There is a solar panel in one shot so that explains the source, but did you run any electrical? If so was it burial grade cable or ran through conduit?
looks great.
Fantastic!!! Ziggy can I ask, would it be possible to scale up this house, for example to build one perhaps twice the size, would the cost be twice as much or would there be problems with design? I would love one of these houses but would need a bathroom and a little more space. I am thinking though that I could still get a really cool house for less than 20k.
Sure, you could certainly scale it up. I can’t say for sure if it would be exactly twice the cost, but that seems to be a reasonable estimate. You would certainly need even beefier roof rafters (and more of them!) Less than 20k for this style of home seems very doable, depending on how resourceful you are.
Sorry, it’s a very interesting project but this can hardly be called a house.
Impressive work!!!
I believe the earlier comment regarding labor was meant to point out that if you worked full time for nine months that is the equivalent of a great deal of money even at the average individual’s income. Since a construction worker’s wage seems appropriate, let’s use that. Though it obviously varies based on location, a good average is around $40,000/year. So, nine months of full-time work for one construction worker equates to about $30,000.
With that math, the cost of the building is about $34,000, or $174 per square foot. Thought that’s a pretty high cost per square foot, you do have the satisfaction of having done it yourself.
Dave: Well, perhaps not according to your lifestyle, but not everyone has the same requirements for a house. A house can be a nothing more than a tent for some. Who is to say what can be called a house?
Matt: Good point.
This is fantastic. I admire your drive and your effort. You have something truly unique. I’m going to blog about it so others can enjoy it as well!
Okay Ziggy, your project is a wonderfull work of art and I realy admire you for what you’ve done.
Having clarified that, now, back to reality: no toillet, no sewers, no shower, no runing water, no heating (winter, you know…), no air flow (summer, you know…), no electricity, no plumbing…etc, etc. Paying 174 bucks for square foot to leave in that conditions, you’ve been robed!!!
I bet you 90% of the people who are so entusistically congratulating you, could not live in that conditions for more than 4 days.
I’m one of them.
But sincerely, congratulations and enjoy it.
Hi Ivan:
Well… just a few corrections: there is heat (the rocket stove heats the bed and bench, in fact), there is air flow (three of the four windows open for a cross breeze), and… well, how did you come up with $174/sq. ft.? I think it’s more like $8-20, depending on if you include labor costs…
But yes. I have no electricity, nor running water. I use a bathroom and shower in a separate building. This is a house built in an community where I can use those kinds of facilities elsewhere without needing my own. But it is important to note, yea.
Thanks!
Congrats, ziggy! You did a great job and it is a very cute house! I think people are missing the point here – if we, as a nation, ever hope to be able to be less of a drain on the world’s natural resources (and come on guys, our current drain is astronomical!) we need to keep an open mind and look to innovators and people like you who blaze the trail for us!! Doesn’t anyone remember the first electic and solar cars???!!! We, here in Eugene, Oregon, laughingly called those versions “the flinstone cars” – huge unwieldy contraptions with many huge heavy car batteries to store power!
Thanks for being willing to accept ridicule to show us a viable option.
Now, you complainers, maybe its up to you to figure out a better way to address plumbing, electricity etc.
Thanks
The first thing that pops into my mind is zoning and building regulations. I live in N.C. and I do not believe there is anywhere a home like this could be built to code. It’s to bad, but today in N.C. there seems to be a building code for everything even in the rural areas.
Ziggy,
I am in the process of selling my house to get started on my wilderness living which has been a dream since I was knee high to a grasshopper! The ONE thing I will not live without is a/c. I am going to move North but still, it sometimes get very hot in the summer even in the North, I cannot tolerate the heat due to a physical condition. How would you run wiring for electricity in the cob house? Does it just go between the layers of cob? I do not plan to “buy” electricity, I will either use wind, water or solar with a back up generator if needed and also a wood burning stove. I do not plan to have lights, I will use oil lamps so really all I need is a/c.
Thanks in advance,
Melissa
you can run the wiring right in the cob, or in conduit in the cob whitch might be a better option
Wow, this is a truly amazing piece of work you have created. It inspires me to do something of the same at some point in my life i plan to live completely off the grid, Solar power, wind, possibly hydro you know the lot. But this Looks so great and cozy. However I would need running water and some electric outlets. Afterthoughts of a toilet, but that would require some forward thinking.
I truly appreciate your work here and wish you health and happiness!!!
-Brandon
Great job, Ziggy! Pay no attention to the critics. Let them live in their stick wood/sheetrock boxes that are prone to fire, mold, etc. Your house may not meet everyone’s needs, but nonetheless you have helped pave the way, showing others how to live more sustainably. Thank you.
Melissa:
Yea, I second what Danny said!
Hi Ziggy, in your list of purchases there is a polycarbonate for sky light???, is there a skylight in the middle of the roof? Is there a hole in the middle of the roof where all the rafters meet and that is where the skylight is?
I am a big fan of TOny Wrench and this reminds me of his home, I am interested in building something really similar.
Beautiful home well done!
Lisa
Duh i see it in the flicker photos now! I was curious how it attached … I get it! (i think)
Ziggy,
I am a natural builder and I focus mainly on Cob. I would like to tell people that the majority of their questions are based off of conventional thinking for conventional building. If anyone has any real interest in cob they should purchase and (read) “Hand Sculpted House” by Ianto Evans, Linda Smiley and Michael Smith. I live in Portland, Or. so I am blessed to have cob everywhere. Plus we have the rebuilding center so getting materials is much cheaper here. I think the cost’s to build the same thing here would be even cheaper. And to that guy in NC. My friends just built a house in NC on an ecovillage next to Duke.
Good job Ziggy, keep up the fantastic work!
Jeremie
Cob Creator
hey ziggy house look great and i bet it sleeps great …..quiet so reading all the comments i think some people are not understanding what you doing and the DR community …ie .. electricity running water ….. there all there but just i another building you have access to the them any time day and night but any way my question hows the living roof and problems come up the EPMD works well just what about the cardboard will it deteriorate over time .
bryan
What a spectacular house!
I am falling in love with cob – I think I want to build a cob house someday, once I figure out where I want to settle down.
How does it handle climates drier than NE MO?
Ziggy, Great home made from an ancient method of building. I’d like to try this method to build a home greenhouse. My climate spans temperatures from 100+ to -45 F degrees, heavy snows, thawing & freezing cycles,t,ornadoes, & heavy rains. Do you think this construction would hold up to the extremes of northern Iowa weather? I’d use skylights, funnel-in water from the roof, and employ solar electricity. Would this construction support a small, solar roof system?
I’ve just been reading about “tractor cob” which reduces the labor of building with cob by about 90%. Pretty nice if spending years building your home doesn’t work for you.
Nita:
-45F is very harsh for cob, since it has pretty much zero insulation. Are you saying that you would like to build a greenhouse with cob walls, though? Can you explain more?
Think you’ve got the right idea of what a house/home should be ziggy,very simple&easy to maintain.What a perfect way to get at least one leg fully out of the rat race.peace of mind comes with simpicity& a humble lifestyle,i bet it’s one of the best places for a good nights sleep.Well done to you sir&all all the luck of the irish too ya
Nita is mistaken on the Iowa extremes of weather. (Lived in Omaha, Ne, both have a humid continental climate system.) The lowest temperature likely to come about is 0F. ( -45F is 45 degrees below Farenheit 0. Arctic Circle temperatures, not Midwest temps. I’m thinking Nita meant less than 45F.) The biggest threat to a cob structure would be the moisture in Iowa, so good drainage, an overhanging roof, and flood prevention would be essential.
kewl
[...] another $400 on a piece of polycarbonate, which is a pretty big expense (especially relative to the cost of the cob house!), or try to find another piece of material to make a second pane. Either way, it needs to be [...]
Ziggy, Your project is great! Can you tell me the difference between cob and adobe? Having lived in the southwest for MANY years, and having lived in an adobe house, I’m very curious. I found the old adobe house to be easily warmed and pleasantly cool in the summer months. The New Mexico climate gave a good test! In my next 78 years, I plan to have either a cob or adobe dwelling! Keep up the good work of informing folks! The basics are BEST!