Green Home Building and Sustainable Architecture

Strawboard Panels

noreply@blogger.com (Kelly Hart) — Sat, 28 Jun 2008 17:37:00 +0000

Strawboard building panels are a kind of structural insulated panel (SIP) designed to replace 2x4 stud and drywall construction for both interior and exterior walls, as well as provide load and non-bearing ceilings, roofing, doors, flooring, and prefabricated buildings. These environmental friendly, solid panels are made of all natural fibrous raw materials, mainly wheat and rice straw. The durable panels feature thermal and acoustic insulation as well as fire and termite resistance and are available for a variety of applications to speed up the construction processes. While these have been used in over 20 countries for more than 50 years, strawboard panels have only been introduced to the U.S. in the past few years.

Strawboard panels have a solid core of compressed wheat or rice straw. High pressure and temperatures forces the straw to release a natural resin that binds the fibers together. The compressed panels are then covered with either paper liners or OSB that is adhered to both sides with water based non-toxic glue. The standard panel measures 4 feet by 8 feet by 2-1/4 inches to 8 inches, weighing from 140 lbs. to 440 lbs. each. Custom panel sizes are available ranging from 3 feet to 12 feet long.

The panel's high density and low oxygen content does not support combustion. Since the panels do not contain added resins, alcohol, or other chemicals, no flammable vapors are produced. The panels have an R-value of between 3 and 25, depending on the composition and thickness. For permanent protection against insects and fungal decay and additional fire resistance, the boron compound polybor can be factory added to the core.

The product's workability is similar to wood as it can be sawn, drilled, routed, nailed, screwed, and glued. Lightweight wall attachments such as shelf brackets, picture frames, mirrors, and towel bars can be attached directly to the panel.

Since straw is a renewable by-product of wheat and rice production that becomes available annually, it takes less acreage (by about half) to build an equivalent house than with standard lumber, and which would then potentially preserve that forest for ecological habitat and CO2 sequestration.

See www.stramit-int.com/ for panels available in Europe and www.agriboard.com for panels available in the U.S.

Thermoplan and Zeigel Blocks

noreply@blogger.com (Kelly Hart) — Sat, 10 May 2008 15:39:00 +0000

There is a manufactured building system that has been gaining popularity in Europe for several years called Thermoplan or Zeigel Blocks. While I have no personal experience with this technology, I can readily see its many advantages. As far as I know this system has not made its way across the ocean to North America. From what I can gather from the websites (referenced below), here are some of the advantages:

Thermoplan or Zeigel Blocks are fired clay blocks which use about 1/3 less energy to make compared to concrete blocks, and about 2/3 less CO2. They are fast, simple and ideal for a self builder to use. About 50% of German homes are made this way and the technology is spreading to other areas of Europe.

Thermoplan systems use Ziegel blocks with a thin bed of mortar, to provide a breathing wall construction system. When combined with woodfibre board they can form a thermally and acoustically high performance shell. The Ziegel blocks come as part of a full load-bearing external and internal wall masonry system, and combine high thermal performance with robustness, speed of build and a breathing wall design.

Because of all the trapped air and the thickness of the walls, these blocks provide reasonable insulation, while at the same time do provide some degree of interior thermal mass for maintaining constant interior temperatures. This is an unusual combination of these two factors in a single wall system.

See www.burdensenvironmental.com or www.natural-building.co.uk for information for this innovative system.

Urban Green Building

noreply@blogger.com (Kelly Hart) — Fri, 25 Apr 2008 16:21:00 +0000

I recently received two emailed questions about the seeming lack of attention to green building in urban settings:

"I happened to notice that very little, if not at all, mention of urban dwellings and how small urban homes are practically the greenest you can get when you factor in transportation. Green homes spread out in the country, unless you're living off the earth and have no use for a car, may counteract your carbon footprint savings if you have to drive on a continuous basis. A vast majority of Americans live in a metropolitan area, it would be nice if your information can include an aspect to the benefits of small homes in urban dwellings."

"I am curious about building an earth covered or underground home in the future. Can these houses be built on a small lot within a city? I think being close to your neighbors etc., is one way to help achieve sustainable living, however, the green homes I have seen always appear to be on a large parcel of land."

I think these folks are absolutely right about this. It is unfortunate that most of the natural building movement has been more of a rural activity...but there is no reason why it has to be. Virtually all of the principles of sustainable architecture that I outline at http://greenhomebuilding.com/sustainable_architecture.htm would equally apply in an urban setting.

In districts where housing goes above 2 or 3 stories, it is difficult to use some of the more natural techniques. One problem is that many of these methods of building result in rather thick walls, especially when the walls must go quite high, so that interior space is compromised by this. This is where some hybrid concepts might be useful, such as building with a steel framework to allow multiple stories, and then fill in the walls with less industrial materials, such as strawbales, cordwood, or earthbags.

As for going underground in a city, it certainly can be done. It would be a great way to create dwelling space and reserve most of the land above for gardening or parks, creating much needed green space in the city.

Also much of the movement towards "sharing facilities," such as co-housing, can be done in cities. This is another way to create both denser housing and reserve open space for parks and gardening.

I think that all proponents of green architecture need to put more creative thought into urban design!

Timber Framing

noreply@blogger.com (Kelly Hart) — Wed, 26 Mar 2008 19:36:00 +0000

When I initially designed www.greenhomebuilding.com I intentionally avoided advocating the use of much wood in building, because of my concern for the health of our forests and their ecosystems, with all of the over-harvesting of timber that has occurred around the globe. There is also the fact that forests help sequester CO2 (a greenhouse gas) from the atmosphere.

This was a difficult choice for me, since my father was a wood worker and I grew up learning many of these skills; I love working with wood and I worked for years as a carpenter. It is certainly one of the most versatile of all building materials, and is a renewable resource, when harvested sensibly.

I have finally come to realize that building with wood (at least partially) can still be a sound ecological choice, which is particularly true in regions where forests have regenerated to the point that they can be harvested sustainably. This means that the trees are carefully monitored to make sure that the health and character of the forest is maintained; only certain trees are culled periodically, leaving the remaining trees to grow and contribute to a healthy ecosystem. It is possible to buy wood that has been certified by the Forest Stewardship Council (FSC), but if this means that you are buying wood shipped great distances, then this becomes a less ecological choice; use local materials!

Furthermore, with timber framing it is possible to use large wooden posts and beams in such a way as to create strong and versatile load-bearing structures, which can then be completed by either in-filling between the wooden structural members, or completely wrapping the timber frame structure with a variety of other materials (as is recommended in colder climates). Since this method of building has been recognized and approved by most code authorities, it is a way of approaching a natural building project that would otherwise be difficult for the authorities to sanction.

So I have now created a page about Timber Framing, greenhomebuilding.com/timber, with lots of media resources and informative links listed. I have also enlisted the gracious assistance of a preeminent timber framing specialist to answer questions from the public about this ancient art.

Will Beemer is a charter member and co-Executive Director of the Timber Framers Guild, and is owner of the Heartwood School for the Homebuilding Crafts in Washington, MA. For over 30 years, this school has been offering students a chance to improve their woodworking and timber framing skills. Will helps teach many courses at Heartwood and has been designing and building houses for over 35 years. He was a construction foreman at the Arcosanti project in Arizona, and design instructor at Cornell University. He has organized and taught building workshops around the world, including timber framing courses through the Guild and at Palomar College in San Diego, the North House Folk School and at the Colorado State University Mountain Campus. He has written for Fine Homebuilding, Joiner's Quarterly, and Timber Framing magazines.

You are invited to visit the new page about Timber Framing and to seek guidance about this art from Will Beemer.

Natural Building Network

noreply@blogger.com (Kelly Hart) — Wed, 19 Mar 2008 16:26:00 +0000

There is a fantastic on-line resource for all people interested in natural building: www.naturalbuildingnetwork.org. This site was initiated in 2005 by a group of people who collectively have considerable experience in the realm of natural building, which they define as "any building system which places the highest value on social and environmental sustainability. It assumes the need to minimize the environmental impact of our housing and other supporting systems while providing healthy, beautiful, comfortable and spiritually uplifting homes for everyone."

The Natural Building Network is a non-profit membership association, where the joining members can place listings for their services and talents and network world-wide. Towards this end, there are directories of natural builders by location, by specialty, and by their willingness to teach others their skills. This helps the members find suitable employment and helps the public find experienced builders who live in their area. Additionally there are classified listings of announcements about related matters. The Network website also features listings of workshops and events around the world, along with resources for further education.

This network and website offer a much-needed central facility for collecting information about natural builders around the world.

Nader Khalili Died

noreply@blogger.com (Kelly Hart) — Sat, 08 Mar 2008 23:24:00 +0000

The Father of Earthbag Building, Nader Khalili, died peacefully, surrounded by his family, a couple of days ago. He was 71 years old.

Here is part of a letter sent out by his family to former students:

“The flames that ignited him in life and the quest that brought each of you to Cal-Earth to learn from him have touched all of us and led us on this path….the right path……. for arts, humanity and the environment. His work and words have inspired us and his spirit is powerfully alive in every work and word, building and echo that your enthusiastic and loving hands have helped to create for this world.

His soul imbues every grain of sand and every memory contained in Cal-Earth, which expresses so much of his personal life of the last 17 years. And your works, like seeds have been growing and flourishing in every corner of the world…”

Born as an Iranian, Nader lived most of his life in the United States, gaining an architectural degree. He worked on the design of high-rise buildings and taught architecture in Southern California. In 1991 he founded Cal-Earth (the California Institute of Earth Art and Architecture) based in the desert region of Hesperia , California. From this center, he taught classes and workshops on the use of both bricks and bags to fashion domes, arches, vaults, and irregular shapes. These forms sprang from his early exposure to Middle Eastern architecture.

The earthbag concept evolved from attending a 1984 NASA symposium for brainstorming ways to build shelters on the moon. He realized that bags filled with lunar “dirt” could be stacked into domes or vaults to provide shelter. This concept was later refined to include stretching barbed wire between the courses of bags to help stabilize the structure. Nader never referred to this building technique as earthbag building; he preferred to call it “Super Adobe,” referring to the fact that he generally filled the bags (or long tubes) with an adobe soil mix.

In 1999 Nader was issued a U.S. Patent for his Super Adobe technique and he subsequently tried to require contractual arrangements for its use. At this point, however, he had been publicizing the idea for so long it was not an enforcable patent, and few would comply with his request.

This fact points to the complex nature of Nader’s personality. He truly loved humanity and the arts, and was an eloquent and passionate speaker. He often said that his ideas were a gift to humanity and he hoped they would provide shelter for the poor and disadvantaged. At the same time, he wanted to control the economic potential of his invention, and he pursued this vigorously.

Nader was the author of several books, including Ceramic Houses and Earth Architecture: How to Build Your Own, about literally making ceramic houses, and Sidewalks on the Moon, an autobiography. He also wrote several books about the the mystic poetry of Rumi. Interestingly, he never really wrote a book about his Super Adobe invention, allowing others to take the lead in doing this.

With the passing of Nader Khalili we have come to a point where his ideas and work can truly become universal. All of us who explore the potential of the earthbag concept and expand on its possibilities can help further his vision for bettering the world. We owe a great debt to this truly inspired individual. May he rest in peace!

Earthbag Tube Forming Machine

noreply@blogger.com (Kelly Hart) — Mon, 21 Jan 2008 23:44:00 +0000

I recently got an email from Steve Cameron with the sketch shown below that he had drawn of a concept for filling and forming earthbag tubing into a uniform rectangular form on the wall being built.

Steve asked for any comments that I might have about this idea, so I wrote:

This is certainly an interesting idea, and a great drawing! I think that I understand your concept pretty well from the sketch. The squared bag shape would only retain that shape if the contents were solidified, as would happen with a soil/cement mix (which you specify); looser material would eventually force the bags into their more natural oval shape after the form were removed.

But then, I wonder, why bother with using the bag material at all? What you describe is pretty classic rammed earth with lifted forms, and there would be better adhesion with rammed earth directly upon rammed earth rather than with the bag material intervening.

If the purpose for forming the earthbags this way is mainly to reduce the work and material in plastering, I have to say that I don’t find the standard approach objectionable. All those crevasses between the bags give the plaster much better “tooth” than a smooth wall would, so there is an advantage to leaving these voids.

I should add, though, that the apparatus and concept is very clever, and shows great inventiveness; I suspect that it would actually function quite well as drawn.

I might mention that rammed earth is often formed with slip forms done in lifts of maybe 2 feet. The proper soil mix is 15-30% clay and the rest sand. Sometime a small amount (maybe 5%) of Portland cement is added as a stabilizer, but not always. This is one area where earthbags have an advantage, because you can get away with a larger variety of soil mixes.

Your suggested mix of 30% cement to 70% soil would be equivalent to a 3:7 mix of cement/sand concrete, which is very rich in cement! Standard soil cement mixes call for between 6 and 16% cement, depending on the specifics of the soil and the intended use.

Then Steve wrote back that the device was actually inspired by a photo he had seen on a site featuring the Natural Building Colloquium in Texas in 2007, which he redesigned to suit his own needs.

Global Warming Media

noreply@blogger.com (Kelly Hart) — Sat, 29 Dec 2007 17:48:00 +0000

Every year I update all of the listings for media at www.greenhomebuilding.com and I am doing that now. Last year when I got to the topic of our environment and books about global warming I was astounded to notice that nearly half of the new titles were nay-sayers trying to cast doubt in the public perception of the issue. Most of these writers were associated with conservative think tanks or corporate interests.

As you might imagine there are many new books written about global warming and its consequences; I noticed over twenty five that were published in 2007. This time, the ratio of nay-sayers has diminished to about a quarter of the volume. I take this as an encouraging trend, in that the real science and public perception are obviously coming closer together. To see a listing of some of new media see this page.

Using Earthbags as Ceiling Insulation

noreply@blogger.com (Kelly Hart) — Fri, 07 Dec 2007 16:13:00 +0000

Dr. Owen Geiger and I have collaborated on a new article posted at earthbagbuilding.com that describes how to use earthbags filled with various natural insulating materials to insulate ceilings or roofs.
There seems to be a general lack of interesting ceiling options using sustainable building materials. For instance, when touring otherwise beautiful straw bale homes one often sees sheetrock covering conventional industrial insulation. Instead of using fiberglass batts or even manufactured cotton batts to insulate a roof, it is possible to use earthbags that are filled with a variety of insulating materials. These materials include rice hulls, crushed volcanic rock (such as scoria), vermiculite and perlite.

The insulating value of these ranges from about R-2 to R-3, so they are quite effective, and can also be quite inexpensive to install.

This article also describes how one might use mats made of natural fibers to cover and finish these earthbag ceilings.

Suspended ceilings, as described in this article, have a number of benefits. They conceal the roof structure, plumbing, venting and electrical wiring, as well as improve acoustics and insulation. And they can also greatly enhance the ambiance or hominess of a room.

Earthbag Building in Haiti

noreply@blogger.com (Kelly Hart) — Mon, 26 Nov 2007 15:28:00 +0000

I spent several hours working on this project page: http://earthbagbuilding.com/projects/haiti.htm

I think it really is one of the best yet, because it shows the entire project from foundation to finish work on a simple home that would appeal to most people around the world; it was created by poor Haitians who had no prior experience; and it was done in a manner that I could easily recommend for others to follow. I think this really shows how earthbag building can really work for people throughout the world.

The house itself is a simple design (with some interest because it is an L shape) and was accomplished without any buttresses. Once finished it is nearly indistinguishable from their customary cement block homes, except that the walls are thicker...and it will be more comfortable to live in I am sure.

This home was built at Pwoje Espwa in Southern Haiti, where Father Marc has dedicated his life to serving and helping suffering children. This project not only houses over 700 children, but has an agricultural project, three schools, carpentry and masonry facilities, and an arts and crafts program. They have many ideas to help the Haitian economy and people living there. Because they are a non-profit, and are continuously struggling with funding, I encourage you to visit their website (www.freethekids.org) and consider making a donation to their cause.

Slide Show of Earthbag Building Projects

noreply@blogger.com (Kelly Hart) — Fri, 02 Nov 2007 15:58:00 +0000

I am very pleased to announce that there is now an extensive slide show of earthbag building projects up at www.earthbagbuilding.com. I spent several days selecting the best photos that I could find and formatting them to fluidly present a marvelous array of architectural styles and approaches to building with earthbags. There are already over sixty images assembled, and I expect to continue to enlarge the library over time.

The pictures are labeled so that if any of them attract further attention, the more detailed description of the project can be found on the projects page.

The pace of the slide show is controlled by the viewer by clicking on arrow buttons below the images, so one can browse as casually as one likes. This is a great way to become familiar with some of what is being created with earthbags. The photos depict both works in progress and completed projects.

So sit back and enjoy the show!

New-crete

noreply@blogger.com (Kelly Hart) — Thu, 25 Oct 2007 15:58:00 +0000

I have gotten the following information from a Canadian inventor who claims some pretty amazing attributes for a product that he calls "New-crete." While it is not yet available, it has the potential to become one an amazing manufactured technology that addresses many issues related to sustainability. See what you think:

I have a patented product of lightweight cement called new-crete. New-crete is designed to form millions of air bubbles when cured. This makes new-crete 50% lighter and stronger than regular cement and 35% lighter and stronger than lightweight cement. It is also 30%-40% cheaper than regular cement. It has an R-20 insulation value with a 9-inch thick wall. It is nontoxic and not corrosive and it floats.

Price: regular cement , $125 per cubic yard; new-crete, $75 per cubic yard
It has the ability to shed water with a .5 mm saturation point. this will prevent water seeping into it and freezing causing cracking.
The ingredients to make New-Crete are readily found around the world and are in no danger of being depleted.
New-crete can be formed into any object. We have the designs for walls, drywall, floors, shingles, stairs, window frames, cupboards, bricks, doors ect....we can make a whole house from the bottom up using only New-Crete
It can be painted, or laminated with wood panels, ect.
It can be nailed into and not crack.

It is designed to be processed in a controlled environment so it can not be poured. That is why we need a $2 million processing plant to start manufacturing pre-fab homes then ship them by train or boat anywhere in the world. Before that, we need about $150 000 to build a prototype home so we can get it approved by CSA (Canadian Standards Association).

Once this is up and running we can start supplying the world with better, cheaper homes. The plans for the prototype home is for a regular box style home. The next step will be to make in-ground and underground domes that are storm proof. They will also be cheaper and strong than regular homes with revolutionary designs...100% self sustainable.

The Canadian north (native reserves) are in much need for about 35 000 new homes as the old ones are in 3rd world condition.

So I know this will be better for everyone, especially the trees. This will change the world. All I need to do is find $150 000 to get it started. I see many people with lots of money (US government spending trillions on war) and the Canadian government also spending money on war ect...the will to change the world is the first key; money will then come naturally.

I believe we must start using other building materials instead of trees before they are all gone. If interested you can contact Matthew Smyth at infiniteearthdesignATyahoo.ca or visit his website: www.InfiniteEarthDesign.com

New Website: www.earthbagbuilding.com!

noreply@blogger.com (Kelly Hart) — Thu, 04 Oct 2007 21:35:00 +0000

I am very pleased to announce the launch of my new website, www.earthbagbuilding.com. Actually this is a cooperative project between myself and Dr. Owen Geiger of the Geiger Research Institute of Sustainable Building (www.grisb.org). Owen and I have known each other for several years and have much respect for each other's work and for the potential of building sustainably with earthbags. To find out more About Us, see this page.

As the banner proclaims, our main attitude is that of sharing information and promoting earthbag building. We expect this to become the premeir site for learning about how to build with earthbags. While the site will be expanding over time, it already has a wealth of information.

Under the heading of Projects and Pictures we have already featured 17 earthbag projects from around the world, and we have plans to show many more. These pages are quite rich with photos and text that explain the nature of the projects, which range from residences to studios to walls to public buildings.

We have already posted 11 Articles about earthbag building, some we have written and some by other authorities on the topic. I have written a short History of earthbag building as well. So far we have 3 articles about Testing earthbag technology.

We have posted 4 pages devoted to the use of earthbags for Emergency Dwellings, and feature several other Plans that are available for more lasting structures.

There is a lengthy section with FAQs gleaned from my years of answering questions from the public at www.greenhomebuilding.com.

Our page of Resources features links to other related sites, books and DVDs that might be purchased, and where to buy supplies for building with earthbags. If you are looking for ways to get involved through Workshops, this page might help you find one.

If you are seeking specific information about this technology, we have provided a couple of Search engines to fascilitate this. One of these is set to search a selection of content-rich resources.

And finally, we are launching a Blog that is specifically about building with earthbags, where both Owen and I will be posting more information and provide a way for you to share information with us through your comments.

I hope you enjoy browsing and benefit from this new resource!

Building with Shipping Containers

noreply@blogger.com (Kelly Hart) — Sun, 23 Sep 2007 23:28:00 +0000

An idea whose time seems to have arrived is the use of stockpiled shipping containers as modular units for building homes. Because of the balance of trade in the United States, these hefty steel boxes are piling up in ports around the country and posing a storage problem. Several architects and builders are taking advantage of this surplus to recycle the containers.

According to David Cross of www.sgblocks.com, "a container has 8000 lbs of steel which takes 8000 kwh of energy to melt down and make new beams etc... Our process of modifying that entire 8000 lbs of steel into a "higher and better use" only takes 400 kwh of electrical energy (or 5%). Granted it takes a bit more "muscle" but we call this Value-Cycling which we feel is that next step up from Re-cycling."

Each container measures 8 feet wide by 40 feet long by 9 feet tall. SG Blocks sells the finished structural systems (also called SG Blocks) for $9,000 to $11,000 per unit. The finished units have one or two walls removed and include the necessary support columns and beam enhancements.

According to KPFF Consulting, a structural engineering firm in St. Louis with extensive experience working with shipping containers, the units are stronger than conventional house framing because of their resistance to "lateral loads" -- those seen in hurricanes and earthquakes -- and because steel is basically welded to steel. The roof is strong enough to support the extra weight of a green roof — which has vegetation growing on it — if the owner should want it.

As for their energy efficiency, they claim that when the appropriate coatings are installed, the envelope reflects about 95 percent of outside radiation, resists the loss of interior heat, provides an excellent air infiltration barrier and does not allow water to migrate in.

One idea that has occurred to me is that this system might benefit from the use of SIP's (Structural Insulated Panels) for the roofs, rather that standard truss framing. SIP's are very well insulated, install quickly, and use much less wood than convention roofs.

Shipping containers are self-supporting with beams and stout, marine-grade plywood flooring already in place, thereby eliminating time and labor during the home-building process. Cross said construction costs are comparable to those in conventional building. Four to seven units are used in a typical home, he said.

Instead of nailing the siding they use "Super Therm", a ceramic paint made by Superior Products of Minnesota; it can be used as a paint, an adhesive, an insulator, a fireproofing material and an acoustic barrier. With this ceramic paint, they claim the insulation capacity is equal to a conventional house.

This finished house is virtually indistinguishable from conventional housing.

Adam Kalkin, of www.architectureandhygiene.com , has also become enamored with shipping containers as an architectural solution. The idea to do something with shipping containers came to Kalkin, a New Jersey resident, when driving to New York City, where he saw sky-high stacks of the unused cargo containers in the shipyards he passed.

"The cargo containers, with a life span of about 20 years when used for their original purpose, have an “infinite life span” when stationary and properly maintained," Kalkin says. “To me they are like a treasured antique: they may not be inherently valuable, but the history and the storytelling add value.”

Environmentalists have embraced the design, applauding the recycling inherent to Kalkin's designs. And advocates for affordable-housing like the design, since according to Kalkin, "the total cost of a house—between $150,000 and $175,000 after the buyer settles upon the various options—works out to be between $73 and $90 per square foot, about half the cost of the conventional $200 per square foot for reasonable quality, new construction in the Northeast.”

Kalkin has recently opened a factory—“a hangar at a little airport in New Jersey”—to manufacture Quik Houses. “There are a lot of elbows flying in this process, and this is the best way to protect the quality of the house, to keep the accounting transparent, and to make sure I am not unwittingly responsible for heinous crimes to the built environment.” Once the factory is fully functional, Kalkin plans to export many of his products, commenting that “the possibilities of working on a world scale are exciting.”

Twenty-one thousand containers hit American shores every day of the year. Containers can be shipped to the interior of the country via trains and trucks. Shipping containers are like Lego toys and the modules can be assembled in thousands of ways.

In general it is a good thing to recycle materials that otherwise have no further use for their intended purpose, and this is true here. As for whether one can make a comfortable house out of these metal boxes, the biggest question is: insulation...it is essential, but there are many ways to insulate these containers, so this is not a big concern. Another concern that many people would have is whether a metal box would have adverse health effects because of EMF (electro-magnetic frequencies) generation or propagation. Some people are sensitive to these while others are not.

There is no doubt that these containers can be used to fabricate very strong shells that would withstand substantial abuse from the ravages of nature.

A Short History of Earthbag Building

noreply@blogger.com (Kelly Hart) — Sat, 18 Aug 2007 20:24:00 +0000

The idea of making walls by stacking bags of sand or earth has been around for at least a century. Originally sand bags were used for flood control and military bunkers because they are easy to transport to where they need to be used, fast to assemble, inexpensive, and effective at their task of warding off both water and bullets.

At first natural materials such as burlap were used to manufacture the bags; more recently woven polypropylene has become the preferred material because of its superior strength. The burlap will actually last a bit longer if subjected to sunlight, but it will eventually rot if left damp, whereas polypropylene is unaffected by moisture.

Because of this history of military and flood control, the use of sandbags has generally been associated with the construction of temporary structures or barriers. Using sandbags to actually build houses or permanent structures has been a relatively recent innovation.

It was an Iranian-born architect named Nader Khalili who has popularized the notion of building permanent structures with bags filled with earthen materials. Actually his first concept was to fill the bags with moon dust! Attending a 1984 NASA symposium for brainstorming ways to build shelters on the moon, Khalili coupled the old sandbag idea with the ancient adobe dome and arch construction methods from his homeland in the Middle East. He realized that bags filled with lunar “dirt” could be stacked into domes or vaults to provide shelter.

Khalili came up with a further refinement on this building concept on Earth: for a more permanent, shock-resistant structure, why not place strands of barbed wire between the courses of bags, thus unifying the shell into a more monolithic structure?

At first Khalili was filling his experimental bags with desert sand, but then he evolved his idea of “superadobe,” where bags or long tubes of polypropylene bag material would be filled with a moistened adobe soil that would dry into large adobe blocks. In this case the original bag material was merely the initial form and would not necessarily be an integral part of the eventual structure.

Soon after these first experiments, Khalili began publicizing his work through newspaper and magazine articles and conducting workshops and seminars on the techniques that he was perfecting. Many people who read about his work, visited his compound in Hesperia, California, or studied with him there, decided to go ahead with their own experiments with his ideas.

Among these “early adopters” were Joe Kennedy, Paulina Wojciechowska, Kaki Hunter and Doni Kiffmeyer, Akio Inoue, and Kelly Hart. I believe that it was Joe Kennedy who coined the more general term “earthbag” to suggest that the bag could contain a variety of earthen materials.

Paulina Wojciechowska was the first to write an entire book on the topic of earthbag building: Building with Earth: A Guide to Flexible-Form Earthbag Construction was published in 2001. This featured some of her early experiments done at Khalili’s CalEarth, along with several other case histories.

Akio Inoue, from Tenri University in Japan, has done extensive experimentation with earthbag construction, both on the campus of the University and in India and Africa where many other domes have been built for assistance programs.

Kaki Hunter and Doni Kiffmeyer (a couple) became enamored with earthbag construction after studying with Khalili, and worked on a variety of projects, both for themselves and for clients. In 2004 they wrote and got published another book, Earthbag Building: the Tools, Tricks and Techniques, based on their particular experience.

Kelly Hart (the author of this article) first began experimenting with earthbag building in 1997, after being exposed to the concept while producing his video program, A Sampler of Alternative Homes: Approaching Sustainable Architecture. He later documented his experience in actually building his own home in another program titled Building with Bags: How We Made Our Experimental Earthbag/Papercrete Home. Both of these programs are now available as DVD’s.

In the meantime, Nader Khalili was continuing the promotion of his “Superadobe” technique and eventually decided to patent the idea, which he obtained in the U. S. in 1999, using very general terms that cover using bags made of any material being filled with virtually any material, and combining these with barbed wired between the courses. While having made many public statements that this concept was his gift to humanity, he obviously wanted to capitalize on the potential economic reward.

Many of us who had been engaged in promoting earthbag building on our own were contacted by Khalili and asked to enter into contracts with him in order to continue our work. It didn’t take much research to discover that his patent could easily be disqualified because he had been publicizing his techniques through various media for at least four years before he even applied for his patent. Patent law clearly states that such publicity occurring prior to one year before the patent application would disqualify it for consideration.

So now the door is wide open for anyone to take this concept and run with it, and more people are doing so all the time, all over the world. While Khalili (and most of his students) have focused primarily on using the bags to form large adobe blocks, others have tried filling the bags with a variety of other materials, such as crushed volcanic rock, crushed coral, non-adobe soils, gravel, and rice hulls.

Earthbag building is unique among all other building technologies in that it can be either insulation or thermal mass, depending on what the bags are filled with. This is a very important distinction, because these characteristics of a wall greatly influence how comfortable, economical, and ecological any given system will be.

Safety is of prime concern with all building technologies, and much experimentation and testing has been done to establish guidelines for many ways of building. Khalili has established a relationship with the building department in Hesperia, California where CalEarth is located, an area where earthquakes are naturally a great danger. In 1993 live-load tests to simulate seismic, snow and wind loads were performed on a number of domed earthbag structures at CalEarth and these exceeded code requirements by 200%.

In 1995 dynamic and static load tests were performed on several prototypes for a planned Hesperia Museum and Nature Center to be constructed using Khalili’s Superadobe concepts with both dome and vault shapes. All of these tests exceeded ICBO and City of Hesperia requirements.

In 2006, at the request of Dr. Owen Geiger of the Geiger Research Institute of Sustainable Building, the Department of Civil and Mechanical Engineering of the U.S. Military Academy at West Point conducted several controlled and computer-monitored tests to determine the ability of polypropylene earthbags filled with sand, local soil, and rubble to withstand vertical loads. Their written report concluded that “overall, the earthbags show promise as a low cost building alternative. Very cheap, and easy to construct, they have proven durable under loads that will be seen in a single story residential home. More testing should prove the reliability and usefulness of earthbags.”

Despite the success of these tests, earthbag building concepts have yet to be incorporated into the International Residential Building Code. Obviously more enlightened acceptance of the demonstrated viability of earthbag building needs to occur!

It is difficult to know how many residences and other earthbag structures have been made at this point, probably hundreds if not thousands. Many of us have been promoting the technique for use as emergency shelters, and certainly some have been built for this reason. It is easy for folks to accept this way of building temporary shelters because it fits the historical model of sandbag use.

But many of us have also built substantial homes using earthbags, and in the process realized how truly versatile and sustainable the technique is. I wouldn’t be surprised if many of these earthbag homes are still standing long after their conventional counterparts built contemporaneously have disintegrated.

Stone Houses

noreply@blogger.com (Kelly Hart) — Mon, 30 Jul 2007 18:05:00 +0000

I recently returned from a vacation wandering around the Ozark Mountains in Oklahoma, Missouri, and Arkansas, and was amazed to see so many stone houses. This style of building has obviously been a vernacular art for at least two centuries, since many of the buildings were quite old. I would estimate that something on the order of 5% of the residential construction in that region is done with stone walls. I don't know if these houses are insulated on the inside (I hope so, given the seasonal heat and cold they must endure.)

This is a picture of one stone house that happened to be for sale, with about 3 acres of land for about $90,000 US. Some of the wood around the windows was rottiong out, but the rest of the structure appeared sound. One of the beauties of stonework is that it can last for centuries and be as sound as the day it was originally built!

Once I got home I was delighted to get an email from Xinyuan, a young woman in China, who was proud of the stone house that she had made near Biejing and completed in 2004. She designed the house and got the help of local construction workers to build it. She expects this to be her retirement home.

Xinyuan is a lover of nature and natural things and wants to promote natural building and life styles in China. There is a tradition of using stone for building in this region.

The house she made is obviously very well-built and quite handsome. The setting near the ruins of the Great Wall of China is also a knockout! Xinyuan would be happy to communicate with like-minded folks, and can be contacted at y.x1213AThotmail.com .

The Enertia House

noreply@blogger.com (Kelly Hart) — Sat, 19 May 2007 17:13:00 +0000

I recently got a query from one of the editors of Mother Earth News regarding a news story she had read in the New York Times. The writer, David Pogue, had been a judge in a contest sponsored by by the History Channel and the National Inventors Hall of Fame titled "Modern Marvels/Invent Now." A $25,000 prize was awarded to one amoung 25,000 contestants, and the winner was the Enertia House, which was invented by engineer and former log-home architect, Michael Sykes.

The Mother Earth News editor said that these homes had been featured in their magazine before. They essentially provide two wooden shells for the home, one inside the other. She said that there was no mention in the article about the cost per square foot. She was wondering what I thought about the concept from the standpoint of sustainable architecture.

Here is my response:

Double envelope house designs have been around for several decades and they definitely offer some benefits, as well as raise some questions. Any house that takes advantage of the geothermal properties of the ground will be doing its inhabitants and the earth a good turn. This can take the form of earth-sheltering in general, or some clever system of circulating air like the Enertia concept; coupled with sensible passive solar design, it is possible to approach a "zero energy" home.

The concerns about their system that I have are: The use of wood as the primary building material is not generally sustainable in this day of lost forests. With the double envelope design, you are practically building two houses to end up with one. Relying on wood as a thermal mass material compromises the potential thermal performance because wood does not serve this function nearly as well as traditional masonry thermal mass materials. So, I guess what I am saying is that a more sustainable and less costly design can be accomplished in more traditional ways.

Answering the same question, Paul Scheckel wrote, "At first glance, this looks a lot like sunspace design from the 70s (without the stone-filled basement to store heat) which overheated in the daytime and lost lots of heat at night. Consider also that this giant convection oven requires a temperature difference, which in this case is driven by the sun and the cool basement. A New England winter has precious little sun, so my heating system will drive the convective loop, increasing heat loss (in addition to the insulation-free envelope). I haven't heard too many people (ie: none) say that wood is bad for houses and better for biodiesel, but there are good arguments for not using so much material in a home. Does it work? I'd like to see one built in the northeast and see the resulting energy data, wherein the proof will lie."

Clark Snell of www.thinkgreenbuilding.com wrote, "I spent five minutes looking over the web site, so these comments are only based at looking at marketing materials, i.e. they may be inaccurate. Ditto what has been said so far. A couple more “red flags:”

Solid wood envelope. They seem to be using the old “mass enhanced R-value” argument for why solid wood walls perform well thermally. I think it’s well established that this is true only in very specific climatic situations. Touting solid southern yellow pine walls in comparison to solid white pine walls is like saying a Chevy Suburban gets better gas mileage than a Hummer…that’s not really a useful statistic.
Energy without oil. The presentation intimates that this is a completely passive design. For example, no heating system is mentioned. That simply isn’t credible for most climates using the technology they are describing.
Passive means local. You simply can’t create a design that relies heavily on passive techniques and generalize it across climates. In my area where we have high humidity, I’d wonder about this convective loop through the attic and basement, for example.

I could go on. I’m a passive design freak, so I’m all for the basic concepts they are dealing with. However, I don’t see anything really new here, but see marketing claims touting what they are doing as a major breakthrough and “the answer”. That always makes me nervous."

David Eisenberg, of www.dcat.net wrote, "After a skimming around their website, I see that they sell kits and their base prices don't include a lot of things - some of which are enumerated:

"Enertia Homes are sold as pre-cut, numbered kits varying in size from 1000-6000 square feet. The kit is a structural package that includes the timbers for the four exterior walls and the two interior walls (Energy WallsTM) which form the envelope, as well as the flashings, gasket, spline and fasteners to put the structure together. Also included are the beams for the upstairs floor system and the rafters for the roof structure. Doors, windows, flooring, and foam SIP roof panels are priced separately as per your blueprint and climate."

That's a pricey list of not includeds and notice they say nothing here and I saw nothing in my quick scan of the site about some really big and typical costs like excavation and foundations, below grade walls, or basement floor. They say this is a structural package but they don't mention all the things that are going to be extra that most people would expect in a house - plumbing, wiring, fixtures (electrical and plumbing), stove, etc. and especially that the solar PV and thermal water heating systems are not part of the package. It would be nice if they said right up front and clearly what they do and don't sell. And they should make it very clear that all the prices include only the factory labor, not the cost of actually assembling and finishing these structures.

But the biggest issue I have is that these are essentially double wall structures using an enormous amount of thick, milled lumber, which appears to use many times more wood than goes into a stick frame house. It would be interesting to see if they use more wood than a comparable log home. They'll likely be more energy efficient than a log home, but they'll use as much or more wood. Which raises all sorts of issues about the sustainability of this venture - beyond just the trees cut down - much bigger transportation, milling, probably kiln drying impacts as well. The concept is fine and likely works reasonably well in most climates. I'd need to see much more actual performance data and of course real cost data to be able to make any kind of realistic judgment of the viability of this concept as anything more than a niche market system. But between the costs which are going to be very high and the amount of materials going into one of these, calling it sustainable seems like a real stretch."

And finally, Jeff Judkoff of the National Renewable Energy Laboratory, wrote: "The concept of "Double Envelope" homes has been around since at least the 1970's. A number of them were built in the late 70's early 80's. Some variations of the concept were published in the Solar Home Book, by Bruce Anderson and Michael Riordan in 1976, Cheshire Books. Other publications in that time frame also showed the concept. The only truly new concept here is the notion that the resins in the wood behave as phase change storage materials. I have no idea if that is true, but I doubt it because the most common phase change is from a solid to a liquid, in which case the resins in their liquid phase would leak out creating a mess. That's not to rule out the possibility that some tree resins could go from a solid to semi-solid phase, or that they are encapsulated in the wood, I just don't know if they can, and would only be able to determine it through controlled scientific testing in a calorimetry chamber. Phase change storage can really be a big boost to the performance of many flavors of passively heated and cooled homes.

There are many ways to acheive highly efficient homes that more or less "heat and cool" themselves. Different approaches have different costs and will work better in some climates than in others. In Colorado, my lab, NREL, worked with Habitat for Humanity to create a net energy producing home. We used super insulation, passive solar tempering, ventilation heat recovery, engineered shading, solar hot water with a backup instantaneous water heater, compact flourescent lighting, and PV. We also have more than a years worth of detailed data to prove the performance of the home (it really was a net energy producer for the last year).

I saw no data to indicate how well the Enertia home actually performed from an energy perspective. Cost, energy performance, and comfort are the key criteria by which to evaluate such homes, and data is always better than arm waving, or catchy theories. Nothing beats the scientific method for objectively determining the value of an idea."

Recycled Houses

noreply@blogger.com (Kelly Hart) — Wed, 16 May 2007 19:29:00 +0000

Awhile ago I was driving down one of our main local roads and noticed a house in the middle of it. I didn't remember a house being there and thought that I was seeing a strange mirage. The closer I got, the more real it appeared, until I was forced to slow down and drive around the thing, at which point there was no doubt about its authenticity.

A big truck tractor was towing this entire 1200 square foot house balanced on two huge steel I-beams and a bunch of wheeled dollies. Progress was slow but steady as it inexorably moved toward its next incarnation. Just that morning it had departed its original home where it had been seasonal housing for migrant workers.

The owners of this seeming mirage had searched for just the right orphaned house to adopt as their own, lovingly place it on a new foundation, and refurbish it. Many houses would not be suitable for such a trip; generally only well-built wooden structures can withstand the stress of such a move. This house had all the qualities they were looking for: charm, integrity, and affordability. The entire cost of the house and having it moved was $10,000.

By the time they have it completely fixed up with new plumbing and electric service, an insulated stucco exterior, new energy-efficient windows, a metal roof, a completely rebuilt front porch, all of the interior walls resurfaced, and miscellaneous repairs, they estimate that the total cost of the project will be about $50,000, including the land. Not bad for what in most regards will be as good as new!

Of course new is not what they wanted; they bought this early twentieth century house (it's actual date of construction is unknown) precisely because of its special vintage quality. It reminds one of the owners of the house his grandmother lived in, with 9 foot ceilings, three smallish bedrooms, tongue and grooved fir flooring, cast-iron radiators, built-in cabinets, drawers and even ironing board, and the intangible quality of a by-gone era. They plan to retain the original floor plan intact, only altering a walk-in closet to become the mechanical room and turning a room off the kitchen into a dining space.

The house made the entire trip with just a few places where the plaster cracked in one corner, which is easily repaired. This is one very solidly-built house, made from the sort of fir that no longer can be bought. There was only one place under the kitchen sink that had suffered leak-induced rot over many years; everything else is as straight and true as any carpenter would want.

Another late twentieth century vintage home of about 800 square feet came from property leased from the Federal government and the house needed to be moved. With local help, the buyer of this little home added an additional room onto the original to comply with the homeowners' association square foot minimum. She has thoroughly enjoyed the process of remaking this simple cabin into her charming home, imbued with the wonderful quirky qualities that spring from her fanciful mind.

Once a house is moved it must comply with current plumbing and electrical codes, so these elements were completely redone. Most of the windows were replaced with second hand units that gave her just the views that she wanted. The exterior was resurfaced with rough-sawn lap siding and a new metal roof was installed. The original interior plastic paneling was replaced with sheetrock, and decorated with lots of natural wood trim. The whole feeling of the place is one of lovingly crafted touches wherever the eye lands. The new owner says, “I would much rather live in something recycled than buying something brand new which has no character. I let this house come together…it just evolved!”

Creating new life for old or abandoned houses has got be one of the most sustainable ways of making habitation. This is the ultimate form of recycling, where most of the basic components of a house are utilized intact instead of being tossed into a landfill or burned. There is a tremendous savings in the embodied energy of the house (in both materials and labor), so that all that needs to be done is to repair and polish the original dwelling to create a whole new life for it. Hoorah for these people who have the vision and willingness to take on these projects!

Yurts: Living in the Round

noreply@blogger.com (Kelly Hart) — Fri, 16 Mar 2007 19:23:00 +0000

Ever since I first heard that Becky Kemery was writing a book about Yurts I have been looking forward to having it in my hands. The wait has definitely been worth it, now that I can see how fully realized her idea has become. Yurts: Living in the Round was published in 2006 by Gibbs Smith, and is the definitive source of information about anything to do with yurts. Not only that, it is also a fine piece of art in its own right; nearly every page is graced with carefully laid out color photos and drawings. Becky's writing is both clear and well researched.

Becky writes, "Most yurts are portable, tent-like structures. They have circular lattice walls (reminiscent of baby gates tied together) and a cone-shaped roof supported by rafters that meet in a center ring. The outer fabric shell of the yurt can be made of felted wool, coated canvas, or a modern architectural fabric. An ever-increasing number of wooden structures are also called yurts. What defines them as yurts and not just round houses? The Answer lies in the yurt's uncommon roof structure."

"The yurt roof incorporates a unique architectural design. Roof struts meet in a center ring, producing inward and downward pressure. This center ring holds the rafters an a state of compression. Where the struts meet the wall at the perimeter, a natural outward thrust occurs. A band (of rope, woven cloth, or wire cable) a the top of the wall holds the wall and roof poles in tension against this outward pressure. Because of this...long roof spans are possible without any internal support system (like posts, trusses, or beams). This gives the yurt an uncommon feeling of spaciousness and uplift. the roof design also creates an incredibly strong and resilient structure that is uniquely equipped to withstand earthquakes, strong winds, and heavy snow loads."

The historical evolution of the modern yurt from its origins with the nomadic Central Asian tribes is carefully outlined. Both the Mongolian Ger and the Turkic Uy are the forerunners of what we now call the yurt. How these tribal folks traditionally make and decorate their portable homes is both fascinating and colorful. This process is generally a group effort and often involves painstakingly felting the wool to make the covering. The traditional pattern of living within this circular space is surprisingly similar to Native American traditional use of space within a hogan, with various family members and guests having their appropriate places.

One of the early modern adaptations of the traditional yurt design was Bill Copperwaite's "tapered wall yurt." These are wooden structures that incorporate the same roof design, but modify the vertical walls to incline outward, giving them a distinctly oriental flare. Bill has been exploring these interesting shapes since the early 1960's, and has come up with quite a variety of forms, including some with concentric tiers of yurts within yurts. Some of them have scalloped butterfly-like roofs; others have gothic arches that surround the perimeter.

The modern fabric yurt is more like its nomadic predecessor, in most ways, except that modern canvas or synthetic fabric replaces the felted wool. Becky chronicles how various people have adapted the original designs to suit modern needs in a variety of climates. Many of the new yurts have central plastic dome skylights and windows that let in lots of light, making them much more open and airy than the darker, womb-like nomadic yurts.

Many of the folks who have experimented with building their own yurts have gone on to make a business of supplying yurt kits for the general public. Becky suggests how to locate and evaluate these yurt companies, and describes various ways that yurts can be adapted for personal needs, such having a bathroom, porch, heater, etc. She even addresses the issues of financing and insuring yurts, and dealing with building code officials.

Another modern adaptation to the traditional yurt is called the "frame panel" yurt. These are much more permanent dwellings than their fabric cousins, and can appear as very solid indeed. They are often prefabricated off-site and shipped to the site for erection. Becky interviewed various people who have lived in these unique homes and shares many insights that could help others who do the same.

The chapter titled "Living in the Round" philosophically evaluates the merits of doing this. Becky writes, "The flexible open space of a yurt is an interior design canvas waiting for the creative expression of each yurt inhabitant. What remains constant is the welcoming embrace of the space, the interaction between inner and outer worlds, and the roof structure that lifts our vision skyward. The yurt also has an inherent ability to bring people together into a circle, which naturally engenders connection and cooperation."

The final portion of the book has several appendices that explore building codes, platform construction, and wood stove installation. There is also an extensive resource guide here for yurt companies, yurt plans, and other media. Becky's website about yurts, www.yurtinfo.org, is another resource providing additional information.

I heartily recommend this book to anyone interested in simple, sustainable living, enduring vernacular architecture, or the possibilities inherent in living in the round.

The Open Architecture Network

noreply@blogger.com (Kelly Hart) — Mon, 12 Mar 2007 21:20:00 +0000

Architecture for Humanity, a nonprofit organization founded in 1999 to promote architectural and design solutions to global, social and humanitarian crises, has just launched a new website to further their goals: www.openarchitecturenetwork.org. The purpose of this network is to allow designers and architects to work together in a whole new way, through the power of the internet to bring diverse folks together to forge new design solutions for housing mankind. This is conceived as an "open source" network, where anyone can share in the process of learning and teaching and building upon each other's work.

They have assembled some powerful software, hardware and talent to realistically pull this off. You will see when you visit the site that many radical design solutions and projects have already been uploaded to entice your involvement.

To help seed the network I just posted some images and description of how to build a small earthbag dome. The process of doing this was quite straightforward and easy to accomplish. I encourage you to check it out and get involved!

Vermiculite and Asbestos

noreply@blogger.com (Kelly Hart) — Tue, 06 Mar 2007 18:12:00 +0000

I have often recommended that folks who want to build with earthbags consider filling the bags with a natural insulating material in order to provide a well-insulated structural envelope. Among the materials that I have advocated is crushed volcanic stone (such as scoria), perlite and vermiculite.

Recently I was brought to task for suggesting the use of vermiculite: "Vermiculite or "Asbestose" as it is better known, is a well-documented product for its cause of lung cancer and silicosis-like effect on tissues. I would hope that you would mention these particular warnings to anyone that might use the "Vermiculite" idea from your page."

I had not heard of this fact, and was obviously concerned about advocating the use of something potentially harmful to one's health. In doing some on-line research into the question, I discovered that pure vermiculite does not contain asbestos, but that there was a period of time when asbestos contaminated vermiculite mined in Libby, Montana did contain some asbestos. This contaminated vermiculite found its way into some residential insulation products sold up to about 1996 in the U.S. and Canada. If disturbed, this insualtion can become a health hazard if the dust is breathed. That mine in Libby has been closed down for several years and is no longer producing this contaminated vermiculite.

Current sources of vermiculite are carefully monitored for this potential problem, especially because of the alert that has been issued by the U.S. EPA. It is my understanding that unless you go digging in someone's attic to obtain the old contaminated vermiculite, there is little danger in using newly available vermiculite.

Here are some of the links that substantiate this:
http://www.schundler.com/verm-asb.htm
http://www.asbestosnetwork.com/news/nw_053003_epa_vermiculite.htm
http://www.ccohs.ca/oshanswers/diseases/vermiculite.html
http://www.radonpro.com/Vermiculite.htm
http://www.karmanos.org/app.asp?id=884

A Dream of Floating Cities

noreply@blogger.com (Kelly Hart) — Sat, 24 Feb 2007 14:50:00 +0000

A woman recently asked me if I might be interested in reading about a dream she had had about future cities. I was imediately intrigued, and said, "Sure!" She then emailed the following to me.

I had to share this dream with you as I found it so astonishing. I think I saw a city of the future. I was touring it as I was waking and continued to tour it as I slowly came alert. I wasn’t amazed until I was fully awake. Never in my wildest imaginings have I ever come up with something like this. Here’s how it goes:

I was looking, first, at a single structure. It was a globe shape similar to the shape of a Spanish onion, which is a rather flattened sphere. It was attached to the ground by a slender stalk and floated several hundred feet above the ground. It was huge, several hundred feet across, maybe even several thousand feet, and had three levels. The stalk held several elevators and water lines. It attached to the earth by a device that was the opposite to anti-gravitation. It also had “claws” that grabbed into the earth but could also be retracted if the structure required moving.

Each floor had within it an anti-gravitational device which was how it remained safely so far above the ground. The floor was some type of plastic which collected heat and dispersed it slowly. It had carpeting over it, all colors, depending on the preferences of the people living there.

The first floor held the sewage treatment plant which was biologically active in that it treated all sewage and organic garbage produced by the population on the second floor. Methane gas was gathered from the sewage and used to produce heat for warmth and cooking. When the solids from this plant mounted up, they were eventually transferred back to the earth as humus. The liquid filtered and recycled into an area where salad and herbal plants were grown for the immediate consumption of the residents of this structure. The left over water from this section was either recycled again or returned to the earth. I guess there were air recycling machines but I didn’t notice any. The silvery plastic type material covering this structure seemed to breathe and allow adequate air ventilation and there were openings around the outside similar to gills. That’s the only way I can describe them.

The second floor contained the residences and housed several hundred people, most of which were family units. The living areas were pie shaped with what we would call the living room on the outer rim, bedrooms closer in and kitchen, bathroom, and laundry close to the stem. I don’t know if there was any use of live fire in this part, as in candles or fire places. It stayed as warm as was needed from the year-round in-floor heating. This heating could be regulated just as we regulate it today. But still, people do like to gather round a fire or burn candles just for the beauty of live flame. I just didn’t notice whether anything like that was used.

The third floor was relatively open with a large space where the residents could run or walk. The very center had a garden of sorts with chairs and a fountain. The people were driving or I should say, flying some kind of small vehicles that didn’t use any of the current methods of propulsion and I guess were equipped with anti-gravity devices as well. They were very quiet and quick. The same thin, silvery material gave this section a partial roof so that there were places to park all around the edge. But the vehicles didn’t stay parked. If they were staying, they attached to the main structure with similar stems where they floated until they were needed.

Then I noticed that there were some of these huge dwellings that had several of these “bulbs” on one stalk. There would be up to five or six floating one above the other connected by a common stalk. These stalks were fairly pliant and could move somewhat if a strong wind came up.

It was the covering that took a great deal of my interest. There were strong cables, again of some kind of metallic plastic, that made up the stalk and the ribs of the structure. They were covered by a skin of a silver, reflective type of plastic. It reminded me of aluminum but looked smoother. It was amazing in that it breathed. It expanded when the weather was hot and became more breathable, then contracted, becoming quite thick when it was cold, thereby conserving the heat. It also darkened as the day grew brighter, similar to eyeglasses we can get now. The ventilation gills around the outside opened or closed as needed. They appeared to respond automatically to the quality of the indoor air. They even seemed to be filtering the air both coming and going. The whole structure almost seemed to be alive and intelligent. That sounds kind of creepy but it didn’t feel creepy. The whole aura was very benign and comforting.

Then I was seeing a great concentration of these spheres and I thought I was seeing Calgary at some distant time, but the city as we know it now was vastly changed. There were still buildings and houses of the type we know today and certainly, historical buildings had been preserved. However, the urban sprawl that the earth suffers from today was totally eliminated. In its place were farms and gardens, parks and forests.

It was so beautiful and felt so vibrant, like it still does in a deep forest now. And the air! It was as clear as crystal from horizon to horizon and smelled so fresh and pure. I could feel my skin being revitalized as I stood there.

Other than the astonishing shape of these structures and the level of cleanliness of this “city”, life seemed to go on pretty well as usual. There were large structures close to the earth but still attached to a stalk, where goods were bought and sold. More similar structures where people met for theatre or dance or some other social endeavour. There were still ground vehicles similar to what we have now but I saw people on bicycles and horse back or just walking or running. It just seemed that humans had found an answer to urban sprawl and a small area could sustain a very large population without draining the earth’s resources or displacing the natural flora and fauna to the extent we do now.

Oh yes, one more thing I saw. Some of the floating cities could have the mooring stem pulled up. Then they became traveling floating cities. They were a slightly different style with more of a dish bottom so that they could set down on water. They just drifted wherever the wind took them. I wondered how they dealt with a potential collision course with a mountain but I never found out. I guess they could be towed away if needed. I expect they could be towed anywhere as their shape would be conducive to easy propulsion or pulling. They were very beautiful. The entire landscape was beautiful, pastoral and quiet and clean. There were lots of roads but not much traffic. I guess most people liked to use the little flying ships if they were going anywhere very far. Some people “flew” out of their home by parachute or hang glider. I saw them sailing away into the distance just like we see hang gliders today.

I would very much like to work with a graphic artist and illustrate them for email. I am still amazed whenever I think of them.

I know why I dreamed of them. I have been studying and using co-creative science through Machaelle Wright’s work called Perelandra. If you would like to examine what she’s sharing with us, her site is www.perelandra-ltd.com .

These cities almost look as if they were grown rather than made. I don’t suppose that’s so. I expect they were made like everything else we do but we are obviously far beyond what we are doing today. All we really need are anti-gravitational devices. With all the advances, somebody might already have something in the works.

Feel free to ask questions or make comments. Others may have seen them, too. Amazingly, my young granddaughter said they looked familiar to her. How about that???

While reading about this dream I was reminded of some of the imagery that I have seen illustrating the books or stories of Cordwainer Smith, who happens to be my wife's father. I found one of these images and have posted it below.

Straw/Cement Blocks

noreply@blogger.com (Kelly Hart) — Mon, 19 Feb 2007 15:19:00 +0000

I was asked to review a manuscript entitled "Development of Straw-Cement Composite Sustainable Building Material for Low-Cost Housing in Egypt," which I did below:

First of all, I applaud anyone who is seeking sustainable solutions for building technologies, as these are essential for our continuing health and success as a species. The aspects of the concept presented for manufacturing building blocks from rice straw and cement that I would consider sustainable are:

One component (the straw) is a surplus renewable material that when utilized will take it out of the waste stream and avoid possible air pollution from burning it.
The straw is free, which lowers the cost of the production
The straw-cement blocks can be produced locally by relatively unskilled labor, again lowering costs
The resultant blocks provide better insulation values than conventional concrete blocks.

On the other hand these blocks call for a substantial component of Portland cement which is known to be a major contributor of CO2 greenhouse gas into the atmosphere. This cement (along with the straw) must be transported to the building site, which also contributes to effective pollution. And the cost of Portland cement is significant ( I suspect much more than the estimated $1.50 per bag estimated in the paper).

If you compare this proposed technology with the vernacular use of straw-reinforced mud (adobe) bricks that have been used since 4,000 years B.C. (according to this paper), then the newer technology does not appear to be as sustainable. Hassan Fathy has clearly demonstrated the appropriate use of mud bricks in Egypt, especially for low-cost housing. Consider these aspects of mud bricks:

Every component (clay, sand, water, straw) is potentially free
Every component has little embodied energy
These materials are potentially available on site, or locally
These building blocks can be used in load-bearing walls, or for other compressive purposes (which the straw-cement blocks cannot)
The mud bricks provide nearly as much thermal resistance as the straw-cement blocks (R-1 per inch)...neither of which is very impressive, especially in a hot climate, but at least the mud blocks provide better thermal mass, so under certain circumstances they will perform better thermally.
Mud bricks can be "stabilized" with a relatively small amount of Portland cement (or asphalt emulsion) for use in circumstances where a greater degree of durability is required.
Mud bricks can be produced with relatively unskilled labor.

In conclusion, if sustainability is to be the criteria for choosing one technology of the other, I ask why introduce a new cement-based product when the older vernacular material (mud bricks) is superior in almost every respect?

Conics

noreply@blogger.com (Kelly Hart) — Sat, 17 Feb 2007 15:48:00 +0000

I have had some comments posted at greenhomebuilding.com for several years about "conics" as an interesting concept for making very thin-shelled curved structures without the need for much of a structural framework. Chuck Henderson from Northern California first pointed out how sheets of plywood can be attached to each other and warped to form some very interesting shapes, as pictured here at the left.

Then a few days ago Avi Rotem from Israel sent me a description with some images of models that he has made of conical structures made with steel beams erected as tripods as a basic support for the sheet metal which is then wrapped over this. Avi would then have a substantial layer of sprayed polyurethane foam, polystyrene sheets, or locally used insulation like straw placed over the sheet metal. A final layer of polymer modified cement would then be applied with wire mesh at its center to provide a strong weather-tight exterior coating.

For more information about these systems, visit greenhomebuilding.com .

The Earthbag Architecture of Akio Inoue

noreply@blogger.com (Kelly Hart) — Sun, 04 Feb 2007 14:25:00 +0000

The technique of building with earthbags has been finding adherents around the world. In addition to the experiments of Nader Khalili in the United States, I know of projects in South Africa, Uganda, Kenya, Afghanistan, Mexico, Japan, Cambodia, China and India. One person who has organized many such projects is Professor Akio Inoue of Tenri University in Japan.

The Tenri University International Cooperation Project responded to the 2001 earthquake near Jamnagar, India by sending a group of 15 students and other personnel, including Akio Inoue as the project leader. They stayed for two weeks and constructed a 20 meter check dam (partially with earthbags), and two bongas (earthbag dome shelters with thatched roofs) near the village of Moda. They also planted 1000 young bamboos to use as roofing material to connect three earthbag domes for an elementary school in the Bolachadi village of the north-eastern area of Jamangar. These three domes were completed by subsequent groups of students over the next three years and were used for a library at the elementary school, which had suffered much damage from the earthquakes. These structures measured about 3 meters in diameter and 4 meters high.

Sometimes they hired Indian workers, but also interested pupils and neighbors cooperated in the building when they covered the completed domes with cement stucco. Built-in earthbag benches provide seating for the students. The interior walls were left as white unfinished earthbags.

In Entebe, Uganda, the Tenrikyo Mission Center assisted Professor Inoue and some of his students with building some small earthbag domes, where they used the abundant soil taken from anthills to fill the bags. These domes are being considered for use as refugee shelters in the region, because they provide good protection from bullets, fire, wind, and rain…much better than the conventional thatched shelters or tents. Also, plans are under way for the construction of a Grameen Pig Bank and a church using the earthbag technique.

In addition to the disaster relief work mentioned above, Professor Inoue and his students have constructed 23 earthbag domes of various sizes in Japan, mostly on the campus of Tenri University as a Model Ecological Design Center. There is a lovely precise symmetry and grace to these buildings that is essentially Japanese in nature, which I greatly admire.