Note: If you’re new to earthbag building, first read the introductory Step-by-Step Earthbag Building Instructable and How to Build an Earthbag Roundhouse . Also, my new Earthbag Building Guide and Earthbag Building DVD are now available.

We built this earthbag dome at our home in Thailand for Mother Earth News Magazine in 2007. The article that describes the complete building process in detail was published August/September 2009. It is now free on the Internet: Low-Cost Multipurpose Minibuilding Made With Earthbags , by Owen Geiger.

This earthbag dome Instructable simplifies the process and illustrates each step of construction with photos. The two critical drawings are also included here. Please refer to the complete article before asking questions.

This multi-purpose dome can serve as a storage shed or cool pantry above ground, or as a rootcellar or storm shelter below ground. No building permit is typically needed, because it is below the minimum size required by building codes, is not inhabited and is not attached to a residence.

Earthbag structures provide a cool space in summer and an escape from the cold in winter (ideal for humans and animals), which means this earthbag dome is well suited for many purposes, like a quiet space for relaxing or playing music, as well as those listed previously. Depending on your needs, the most practical combination of uses might be a rootcellar/cool pantry for daily use and a disaster shelter for emergencies such as tornadoes or hurricanes.

The key concept that makes earthbag domes work is corbelling. This means each course (each row) of bags is inset slightly from the course below. Corbelled domes made of adobe and stone have been built for thousands of years. The concept has been applied to earthbags in the last few decades.

Basic project information:
18’ exterior diameter; 8’ interior diameter; 11’ exterior diameter, 50 sq. ft. interior floor space; total cost of materials: $300, which is about $6/square foot.

Tamper(s), round nose shovel(s), grape hoe or grub hoe (digging tool), 13” x 16” sheetmetal slider, knife, hammer, 2’ level, 2” x 4” x 10’ leveling board, tape measure, fencing pliers, handsaw, trowel, garden hose with spray nozzle, 6’ or 8’ stepladder

The following instructions assume you have cleared and leveled the site, removed topsoil, positioned fill soil around the building site to minimize work, dug a trench to stable subsoil, put about 12” of gravel in the trench, and added two stakes with string lines: a center stake with string line to measure the radius, and a stake in front of the door to measure the dome curvature. Bags or tubes can be used. We demonstrate bags, because they’re often available recycled for very low cost. My YouTube Channel has a short video showing how the dome was built.

Step 1: Dome Plans

Let’s briefly take a look at the plans so you’ll better understand the building process. The first drawing is the floorplan that shows the dimensions for the dome base and the angled buttresses in front. The buttresses provide reinforcing on both sides of the door and also act as retaining walls to hold back the earth. Make a rubble trench under the buttresses the same as the dome, and interlock (overlap) each course where the dome and buttresses intersect.

The second drawing is the dome section that shows key vertical dimensions, earthbag foundation, door and arch. Note the wood stake in front of the door. The string line on this stake guides the curvature of the dome (112” radius in this case). This dimension remains constant. Put the stake off to one side of the doorway so you’re not tripping on it during construction.

<p>You kind of remind me of Gandalf or Dumbledore.</p>
<p>dome need a window</p>
<p>Are you a Hobbit?</p>
<p>So AWESOME! Love this Instructables!</p>
<p>aiy yu qwee owen. we are in the middle of building an earthbag house (training with united earthbuilderwe live in california on the yurok reservation, right on the river, lots of trees,etc. my friend leslie hunt said she spoke to you recently, she lives on the next reservation over, hoopa. i am wanting to add a mud room with walls made out of large food cans but havent found anything on line to see if it works. we are trying to build out of what we have close, and there are lots of these large food cans on the next reservation in hoopa. have you ever done this or seen this done?</p><p>ive been wanting to build our own home since i watched your film years ago, thank you for your inspiration. we plan to help others here on the reservations build, we have high unemployment of course, people live in shacks, no electricity on half of the reservation, we declined the poles ourselves. so we need to make them as cheaply as possible. all of your information was very helpful to us, thank you.</p><p>wohklow, </p><p>monique sonoquie</p>
<p>Developing a new building system takes a lot of time and effort. Better to stick with what's well proven. Look for recycled bags from locals farmers and start experimenting with small structures like outhouses and tool sheds. Good luck.</p>
<p>OH MY GOD!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!</p><p>:D!!!!</p>
You could plaster the dome with hemp plaster or a layer of hemp cement and then add soil directly onto that!
<p>I'd like to see it from the inside!</p>
Its a hobbit hole!
<p>Can we see the inside? How does it stack after a few years for keeping the inside free of insects that burrow through soil?</p>
<p>Like I've said several times, it's tiny inside and hard to photograph. You can find similar photos on the Internet of other earthbag domes. (Really cool looking.)</p><p>No insects can tunnel through all that soil and through multiple layers of plastic sheeting. BUT some plant roots (vetiver grass?) managed to puncture a hole in one place. We peeled back the sod, added some more plastic sheeting and put the sod back. Total repair time = 5 minutes. No damage to the earthbags because I caught it quickly. Use a more durable roof for homes: rubber bituthene instead of plastic sheeting.</p>
<p>Extremely cool.</p><p>I may never build a house like this, but I'm glad to know you did.</p><p>I'll bet it's also cool inside when it's hot outside. </p><p>Thanks for the Instructable.</p>
<p>Yes, it's always cool inside -- the same temperature as the earth. The door is facing away from the afternoon sun so it never gets hot inside.</p>
<p>How hard would it have been to include windows?<br>How would you do that?<br>And yes, we'd like to see photos of the inside of THIS structure.<br>Thank you again?</p>
<p>Most domes have windows. This however is just a tiny tool shed. Search the Internet for images of earthbag domes. Most have arched windows. There are various ways of making windows. I like to include ferrocement 'eyebrows' over windows to block sun and moisture.</p>
<p>Owen. <br>That is one hell of a lot of work for &quot;a tiny tool shed.&quot; Actually, kind of insane. But the Hobbitliness of it is amazing, the beauty of it is endearing, and your raw determination to do something wonderful is inspiring. <br>Thank you from all of us out here in &quot;2x4 studs on 16-inch centers&quot; land. Keep doing what you're doing and keep us posted every step of the way. Like I said above, I may never build like this, but it is wonderful to know that you are doing so with enthusiasm and success. <br>Please, please, send us updates and Instructables on a regular basis. This is among my very favorite all-time Instructables. <br>And I know that I am not alone.<br>Best, Rich</p>
<p>For those interested in ongoing projects, please follow our Natural Building Blog. <a href="http://www.naturalbuildingblog.com/" rel="nofollow"> http://www.naturalbuildingblog.com/</a></p><p>We have over 2,000 blog posts on every topic you can think of, and it's all free.<br></p>
I LOVE this. What do you think is the largest dome you could build this way?
<p>Somewhere around 20' interior diameter is about the limit. That would be 23' exterior diameter.</p>
<p>Somewhere around 20' interior diameter is about the limit. That would be 23' exterior diameter.</p>
Thank you Owen for all your wonderful information! <br>You have inspired my son and I to build a semi subterranean earthbag dome. <br>We have been hard at it for 2 months now and are finally getting close to the top. <br>It has been a learning experience to say the least! <br>Wanted to ask your opinion about waterproofing material. <br>Our plan is to have a living roof when we are done. <br>I am looking at the different materials available and it is all kinda confusing. <br>You suggested using 6 mil sheeting. Could we use recycled 5 mil tarps as we have no budget. Also what do you think of a light weight roof underlayment? <br>The material is a little pricier but would it offer any better protection from leaks? <br>We want it to last forever. Thank in advance! <br> <br> http://www.lowes.com/pd_283849-711-5008030_0__?productId=3151833&amp;Ntt=roofing+underlayment&amp;pl=1&amp;currentURL=%3FNtt%3Droofing%2Bunderlayment&amp;facetInfo= <br> <br>
<p>Last forever, ha! Tarps should last for quite a while. Eventually though insects, rodents and roots will puncture through.</p><p>The most durable roofing for this purpose is rubber bituthene, but it's super expensive.</p>
<p>My dreamhouse! I wonder how it could resist in a northem climate</p>
<p>Add waterproof insulation on the exterior for cold climates. Search for my article and blog posts about Insulated Earthbag Houses.</p>
Build a life size model of Bag End. Challenge Accepted.
<p>on a related note, would giving this a circular door have any effect on stability?</p>
<p>Sure, you could do that. </p>
No, no, no! Build a life-size model of Hobbiton, wait, no, The Shire!
Wait a second, is this why Bag End is called Bag End?
&quot;The name comes from the farmhouse in the tiny Worcestershire village of Dormston, in which Tolkien's aunt lived. It can also be seen as a pun on &quot;cul-de-sac&quot; (literally, &quot;bottom of the bag&quot;).&quot; - LotR wiki. <br> <br>More to the point, it's also a slight pun on &quot;Baggins&quot;, since if you say &quot;Bag End&quot; quickly as one word, it sounds not entirely unlike &quot;Baggins&quot;.
Oh, I know it's Bag(gins) End - I was just fooling around.
Of course. Owen Geiger's real name is J.R.R. Tolkein.
<p>i wonder about the inside how does it look?</p><p>is there any possibility to take a picture of it</p>
<p>It's really tiny and hard to photograph the inside. Search earthbag dome images on the Internet and you'll see lots of similar photos of larger domes.</p>
<p>i look at this instructable every 6 months since it came out just because it's so boss.</p>
<p>Whoa, thanks.</p>
<p>excellent...no words for it.</p>
<p>Could you live in this???</p>
<p>I'm going to build a play house for my daughter using this. It WILL happen. Someday.</p>
<p>It's not a nasty, dirty, wet hole filled with ends of worms and an oozy smell, nor yet a dry, bare, sandy hole with nothing to sit down on or to eat: it's a hobbit hole, and that means comfort. </p>
<p>haha! so glad someone said that! it was on my mind the whole time!</p>
<p>it does look like a hobbit hole just needs a round door</p>
<p>this was the coolest thing ive ever biult </p>
<p>This is so awesome!! Want to make one for me?</p>
<p>This is truly brilliant</p>
<p>This is truly amazing and brilliant!!</p>

About This Instructable


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Bio: Owen Geiger is the former director of Builders Without Borders, a Mother Earth News Green Home Adviser, The Last Straw Journal Correspondent and the director ... More »
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