Hello all my permie friends, I have been researching earth bermed housing for quite some time, about 5 years, I am now settling on a design which balances price, sustainability, time to construct, and aesthetics. I have decided on a monolithic dome made of geopolymer and geopolymer air-crete for insulation with arches for windows doors and straight furniture. I would like some input on my design ideas from all you walking, talking, parallel processing, pattern recognizing super computers.

I have looked at the WOFATI design that Paul likes but I would prefer a round domed structure for aesthetic reasons and because of the fact that it is the strongest possible structure in nature. WOFATIs also have a limited life span as they are a wooden structure. I know that life span is probably 80 years or more but I would like something that could last centuries and house generations of people.

Pros: cheap to build; strong structure; very local sourced materials; fast to build
Cons: limited life span; requires an impermeable layer to prevent water infiltration; wood posts require protection where in ground; not round or domed

Next I looked at earth bag and super Adobe building methods. These methods are cheap, easy to learn and provide very strong structures that can bermed. However it does take a lot of labor to fill bags and I am not a big fan of using synthetic materials for the bag. That is of course a personal choice.

Pros: cheap to build; can be built into a circular domed structure; very strong structure; fire proof; flood proof; earth quake proof
Cons: uses synthetic materials; lots of time and labor; difficult to build a "perfect" dome; requires a synthetic impermeable membrane

Monolithic domes are real super structures. They are fire proof; flood proof; earthquake proof; tornado proof; hurricane proof; and bullet proof. They will last centuries if not longer and are the strongest structures we know of. They can be built in a single day by using inflatable air forms and shot-crete and insulation can be made by mixing in a foaming agent. Arch ways provide flat surfaces on the otherwise rounded dome for windows, doors and to connect more than one dome.

Traditionally monolithic domes are made of cement but as cement tends to crack, is hydrophilic and produces a lot of co2 in its production I wanted to find another material to use. Geopolymers are cement like substances made from a variety of rock dusts, fly ash, or iron blast furnace slag and a strong base like lye or sodium carbonate. All of these materials are either waste materials form industrial processes or are very inexpensive. Geopolymer are essentially man made rock. Recent research suggest that the pyramids in Egypt were made from artificially made lime stone blocks instead of blocks being mined from quarry. These man made stones are almost indistinguishable from real lime stone and they last of course for 1000s of years. Geopolymer shave up to twice the compressive strength of cement and up to three times the flexibility. I have also read that they are self healing if cracked but I have not a confirmed that.

A monolithic dome made of geopolymer would potentially not require a impermeable layer when bermed as it is one solid piece of rock.

Pros: everything proof; relatively inexpensive; lasts potentially for 1000s of years; can be built in days; aesthetically beautiful; very modular (easy to add additional domes)
Cons: needs some experimentation to create the proper mix of geopolymer precursors; permitting; need inflatable air form and pump.

I will post some videos and links to some of the stuff listed above. I will also work on a drawing of the house perhaps in google sketch up. In the mean time I would appreciate any input, critiques, ideas, or perhaps you can tell me how crazy I am.

Monolithic Dome Help

I love geopolymers. I also have seen some incredibly nice homes in caves/old mines in the appropriate environments for them. I think with the correct skill sets, motivation and money anything can be "made to work." I love the concept of Wofati, and think some could last millenia if built properly.

As a natural/traditional builder, I can't say I have ever seen a "modern dome" work survive much past 20 years without major issues...

I think brick/stone domes/vaults have great/excellent potential, and though I don't believe "modern domes" work (or have proven to) I love traditional domes of all types starting with Brunelleschi's Dome. In the vernacular forms, like cloister (ambulatory) vaults, caponier in domestic application, timbrel (catalan) vault...this is one of my favorite forms/types!!, groin vault, muqarnas (stalactite vaults)...and it rambles on....

Auroville Earth Institute is a wonderful place to explore the possibilities of such structures in the methods that have historical/empirical positive track records...

Jay C. White Cloud wrote:Monolithic Dome Help

I love geopolymers. I also have seen some incredibly nice homes in caves/old mines in the appropriate environments for them. I think with the correct skill sets, motivation and money anything can be "made to work." I love the concept of Wofati, and think some could last millenia if built properly.

As a natural/traditional builder, I can't say I have ever seen a "modern dome" work survive much past 20 years without major issues...

I think brick/stone domes/vaults have great/excellent potential, and though I don't believe "modern domes" work (or have proven to) I love traditional domes of all types starting with Brunelleschi's Dome. In the vernacular forms, like cloister (ambulatory) vaults, caponier in domestic application, timbrel (catalan) vault...this is one of my favorite forms/types!!, groin vault, muqarnas (stalactite vaults)...and it rambles on....

Auroville Earth Institute is a wonderful place to explore the possibilities of such structures in the methods that have historical/empirical positive track records...

That is a very good point Jay. I could see how a monolithic structure would be subject to forces that might crack the dome as it is one solid piece. A dome made of individual bricks would potentially absorb forces without cracking. Something to consider anyway. Hmm perhaps a dome made of geopolymer bricks. It would take longer to build but that is not a huge issue as it would last a very long time. I definitely want a round domed structure made of a natural material and earth bermed. The plan is always evolving.

I love geopolymers

I have to say, I agree 100% with you there! I've been reading up on them a bit and it's fascinating. That, and I have an idea as to how an enterprising permie might make one in their very own backyard, assuming they had some knowledge of chemistry.
Sodium silicate (aka waterglass), when combined with fly ash and water, seems to create a relatively strong geopolymer. A quick search of "fly ash and sodium silicate geopolymer" brings up a great number of papers measuring compressive strength and plenty of other important factors meant for people much smarter than me.
The great thing here is that fly ash is a waste product of coal (and some electric-fired) powerplants, and is a pretty big component of most land fills. A cheap waste product that would end up in a landfill or dump if I didn't use it? How could it get any better?? Reminds me of people using shabby old tires for rammed earth thermal mass.
Another big plus is that just about anybody could make sodium silicate in their backyard, if they were careful and (again) had some knowledge of chemistry. Just take lye, aka sodium hydroxide, (easy enough to buy or make by filtering water through wood ash) and dissolve it in water. Then add silicates, and you've got waterglass! On a small scale people suggest using those little "do not eat" packets of silica gel, but you can actually use a different source of silicates...sand! It is, of course, more complicated and a little more dangerous than that if you're trying to use just clean sand rather than lab-grade silicate, and I wouldn't suggest anyone try it unless they know more about it than I do. That said, I think it's a pretty cool little bit of information.