Domes & Embedded Energy
Off the keyboard of RE
Published on the Doomstead Diner on April 13, 2014
Discuss this article at the SUN Table inside the Diner
Interview: Monolithic Domes Founder David South
Eddie did some chronicling of the daily learning that went on at Monolithic Domes, in retrospect now that the Workshop is over I thought I might take some time tonight to look at the Bigger Picture with respect to Domes in general, and the Monolithic Method in particular.
Wednesday’s workshopp was particularly rich in information of sorts I did not have specific knowledge of before, parameters for building ferrocement domes and making them solid and resilient on the engineering level. A remarkably few people are expert in this stuff, and David South has more experience with more Domes up globally than anybody else. If you want to know domes of this type, this is the go-to guy. Not just for Doomers, but for everyone from the United Nations to various Saudi Sheiks and the NASCAR folks too.
The Monolithics though are quite energy intensive in the building, and at least for the larger scale domes need quite a bit of high tech materials and equipment to put up. Not outrageous when you consider the scale of some of these domes and the fact a crew of 5-10 people can put one up, but still quite a bit of stuff that will be hard if not impossible to come by in the not too distant future. That includes particularly the polyurethane foam that forms the initial dome structure, the Dome Balloon Vinyl skin, the Basalt rebar and the pumps used for spraying the Foam and the Shotcrete.
The fact construction of the larger domes depends on these materials and equipment does not diminish their utility NOW though, while they still can be constructed at a reasonable price. The ferrocement structure itself can last a very long time, providing good shelter for years to come. So it makes sense to build such structures now while you can, embedding the energy into the structure, as opposed to burning it simply for the purpose of willy-nilly Happy Motoring.
Such large Open structures have a multitude of uses as well, and given they are resistant to disasters such as Hurricanes, Tornadoes, Floods, Earthquakes and Wildfires they make a lot of sense where Climate Change is a preeminent problem. They are quite airtight as well, which could be important in scenarios where Nuclear Fallout is a problem. The structures can be purposed for indoor intensive food production through Hydroponics, Aquaponics and Aquaculture; in fact in the next year the Monolithic folks are planning on putting up a Commercial Facility for just this sort of production on the campus of the Monolithic Institute.
The inability to acquire and use some of the tools and materials that enable the construction of the really BIG DOMES does not eliminate the potential for building quite similar domes on a somewhat smaller scale utilizing similar methods, and during the week here the Diners attending the course have been Brainstorming on ways to adapt the building techniques to more locally available materials, renewable structural components like Bamboo, and substituting Human Labor for operations currently done with the aid of fossil fuel powered machines. Although the 100′+ Domes possible with the Monolithic Method aren’t possible with such materials, it is probable you could construct Domes in the 50′ range utililiIng natural fibers, adobe or cobb, and finishing with concrete reinforced with various materials either scavenged or grown. Such smaller domes would be quite capable of doing the same things the larger ones do, you would just need to construct more of them. We hope to begin experimenting with some of these ideas over the months to come and we will report more on this on the SUN Website.
A primary area we are looking at in terms of utilizing the Monolithic methods for Housing in the near future is for providing Affordable Rental Housing in the $150/week range. With many people descending from the Middle Class into the ranks of the Working Poor, the need for this type of housing is apparent, and the Domes provide a means to build this up in a modular fashion without taking on a lot of debt.
The fundamental weakness as far as the Monolithic method is concerned is its dependence on the high tech material used for creating the Balloon used as a framework/scaffold for spraying polyurethane foam and hanging rebar and either spraying “shotcrete” or trowling on concrete by hand. The high tech materials are likely to become unavailable as the economic system further deteriorates, so the ability to build the domes using these items will eventually disappear.
The loss of the high tech materials doesn’t make the construction of ferrocement domes impossible, there are other methods available for doing this, at least on the small-medium scale. The largest domes in the 100′+ category likely become impossible to build without access to these materials. However, the basic construction materials of aggregate and rebar will likely be available a good deal longer, and can be used to construct both smaller domes as well as other types of structures.
Given these parameters, the sooner we get to building the larger domes the better, and constructed with Basalt Rebar (another high tech product), these domes will have an extremely long lifespan before they fail. Because concrete is porous to water, eventually using Steel Rebar for reinforcement this will rust and fail, after which the concrete will eventually crack and begin to collapse. Once the integrity of the Dome structure is compromised, the rest of the dome becomes rubble shortly after that.
Why is it important to get the domes up now while we still can? First, because of their utility and efficiency right now, second because as shelter, they will last a whole lot longer than the current McMansions we are using for shelter. They are also multi-purpose, with the open space of the interior useful for indoor growing methods, which will likely become increasingly important as climate change continues to wreak havoc with conventional farming methods.
While the largest domes built using the Monolithic techniques are quite impressive, such large structures really aren’t necessary, and in some cases actually counter-productive. In the case of using them as grow domes for hydroponics or aquaculture, if at some point the water system becomes contaminated you lose an enormous amount of the produce in one shot. On the other hand, if you grow a similar amount through smaller distributed and independent domes, an infection in one system doesn’t affect the other ones, so such a system is more resilient.
In the long term, the domes in the typical size range of 20′ to 60′ in diameter, not all dependent on the high tech materials and equipment that the Monolithic domes depend on. These domes are the most easily constructed by individuals at relatively inexpensive costs, with a variety of materials possible to use in reinforcement as both basalt and steel rebar become less available. Far as Cement and Aggregate are concerned for making Concrete, the limestone is available locally and there is no shortage of sand. What will be difficult of course is moving such heavy stuff around without fuel to run the trucks.
Although the Monolithic Domes once constructed are an extremely energy efficient structure, the materials and methods used to create them represent Embedded Energy which is available right now, but is unlikely to be available as we move forward into a low available energy world in the future.
Realization that this is the medium to long term case first means that it is worthwhile to build as many of these types of domes as possible now, and make them as long lasting as possible. For this purpose, the “Ecoshell” construction method using just Concrete in conjunction with Basalt Rebar that doesn’t rust can create a dome with the potential of lasting Centuries with no maintenance, and the vinyl balloons used to scaffold the ecoshells can be reused many times. Although these structures lack the insulation values of the Monolithic Domes, alternative means of Insulation can be applied later which may not be as long lasting as polyurethane, but can be periodically renewed from locally available materials. Given the cost of the balloons also, the ability to reuse them many times substantially decreases the cost per building as the number of buildings created w ith it increases.
Monolithic Domes dependence on high tech materials presents a weakness as a long term solution, but are very useful now in the preparation phase and transition to a lower per capita energy world. Moreover, many of the techniques can be adapted to more locally available and renewable materials. Embedding available energy now into these structures can go a long way toward easing the transition off the Fossil Fuel Jones.