Outdoors, Green Living, Homesteading, Sustainable living, Green Building

Green Building

The Mongolian Yurt

WANTED! Comments. Not wanted! Compliments. If you want your comment to be accepted first you must not be a spammer that WordPress recognizes and second you need to comment specifically on some of the article’s specific material or facts.

The Survival Pod Cast
Off Grid Net

What is a yurt? Is it a tent? Is it a hut? Is it a shack? Is it a cabin?  Pick up the book titled, “Build a Yurt!”  This book was written by a guy in the 1970’s that actually visited Mongolia. This web site has a nice gallery of yurt photo’s. Yurt Gallery Yurts are actually called a Ger in Mongolian. Ger means home or dwelling. It is a light wooden frame, circular like the native American Tee Pee, yet shaped more like a short grain silo. I think we have all seen grain silo’s in America. It was probably covered in hides by the Mongolian’s. They may have used some heavy cloths (canvas) as well. It was insulated with thick felt made from animal hair. They were tied down with stakes and guy ropes or chords, in the similar fashion as tents. Yurts have a sky light at the top which serves a similar purpose as the hole in the top of the Tee Pee.

You may want to read a related article Green? my blog post on the green building trend and green living.

Yurts were known to withstand hurricane strength or blizzard winds of around 90mph(144kph). They are as strong as most of our buildings when it comes to wind resistance. Since yurts are round houses they are very energy efficient to heat. Yurts consist of a frame of 1 inch(2.5 cm) by 2 inch(5 cm) or 1 inch(2.5 cm) by 3 inch(7.5 cm) sticks or ribs. These are oriented in a lattice work pattern for both the side and the roof support. Of course these can be built right on the ground or on any kind of floor and foundation. I list here a parts list for a yurt which will be 22 feet(6.7 m) in diameter and have about 7 foot(2.13 m) side walls. It will rise to about 12 (3.6)  to 14 (4.2) feet (m) in the middle. This yurt will be constructed on a wooden floor which will be about 2 feet(60 cm) above grade (ground level).  It will have one door and the sky light and possibly some windows. When completed it will have 400 square feet(37 m2) of dry floor space.

11.33 foot (3.45 m) radius. 22.66 foot (6.9 m) diameter. 403.2 square(37.43 m2) foot floor space. 71.18 foot (21.69 m) circumference. Here is a Yurt Math PDF The side walls will be built with sections of lattice. The lattice is made from 1×2’s and will be about 8 feet long. The roof lattice will be made from 1×2’s(2.5x5cm) and 1×3’s(2.5×7.5cm) The 2(5cm) inch side will be on top and laid horizontally. The 3 inch(7.5cm) side will be vertical and function similarly as rafters.

Wall Lattice

Roof Lattice

Parts list

  • 140-1″x2″x8′ (2.5cm x 5cm x 2.43m) sticks for wall lattice.
  • 70-1″x2″x12′ (2.5cm x 5cm x 3.65m) sticks for roof lattice.
  • 70-1″x3″x12′ (2.5cm x 7.5cm x 3.65m) sticks for roof lattice.
  • 3/8″ (9.5mm) steel cable 75 feet(22.86m) long (for the 70 foot (21.33m) perimeter)
  • Rope for guying. Or cable for guying.
  • 6 to 8 Wooden or Rebar Steaks
  • Turn buckles for tightening the steel cable.
  • 6 to 8 Cable clamps.
  • Small finishing nails.
  • 4’x4′  (1m x 1m) foot piece of Plexiglas (for the sky light).
  • Side covering. 8 feet by 72 feet in size.  (2.43m x 21.94m)(canvas or vertical wood or tin) Contact an awning maker for this.
  • Roof covering. This is a cone shaped piece. in 11 feet the roof will rise about 5 feet(1.52m).  (canvas or wood shakes or tin) A circular piece of about 25 feet(7.62m) in diameter might work. The circumference would need to be 71 to 80 feet(21m to 24m) maybe.
  • 500 feet (150m) of Nylon chord for tying down the roof covering, if the roof covering is made of some cloth like material.
  • Linseed oil, to be rubbed onto the lattice pieces.

Parts list for the floor.

  • 6, 6″x6″x11.33 feet in length beams size (can be larger than 6×6 such as 6×9). The angle between the outer hexagon beams is 120 degrees. The angle between the main beam across the middle and the diagonal is 60 degrees.
  • 1,  22.66 foot  6×6 (6×9)  beam.
  • 44- 2″x6″x10′ for floor joist spaced every 1 foot
  • Or 22- 2″x8″x10′ for floor joist spaced every 2 feet (if used 6×9 beams)
  • Joist hangers, metal sheeting for custom hangers, or pipe strapping. If using strapping then toe nailing is required. Do not end nail for support.
  • 1x planks for flooring. If 1×4 will need 132. If 1×6 will need 88. They will be 10 foot long. Planing and tong and grove jointing would be nice.
  • Plywood for cantilever floor support. This is for the edge that hang over the beams. Figure a 71 foot circle then draw a line from one edge of the circle to another edge which is 11.33 feet long. There will be 6 such areas.
  • 100’s of 16 penny nails or long wood screws.
  • Stone or blocking for support to lift the floor 1.5 feet off the ground.
  • Linseed oil for some rot protection (to be sprayed on beams)

Main Floor Frame Beams.

Floor with 2x6 joist on top and 2x8 joist on bottom.

An insulated floor might need these parts..

  • 6 mil plastic to be draped over the joist.
  • Fiberglass Batt insulation.
  • Or wheat straw as insulation. (if I used this I think I’d want a light weight plywood underlay.
  • Staples and Staple gun.

Other ideas..

Fly Screen might be needed on top and sides to keep insects out.

Instead of the yurt lattice for side, consider a normal 2×4 stick frame side. For the top use two layers of 1″ plywood pieces cut in circular fashion to make a wall plate or 2×4 pieces with angles cut to fit perfectly between studs. A metal top plat would work well also. Use metal plates and sheeting for extra support.

A tin roof with standing seams would be easy enough to make. Would need pieces of tin that were about half a foot wide at the top and maybe 2 or 3 foot wide at the bottom. Top to Bottom edges would be bent up at about 2 inches. You would lay these side by side then use some tool to bend the seam of the edges of two pieces over once then twice. These pieces would be nailed at the top. Something at the top would cover the nail holes, such as the plexiglass sky light cover.

Cost of a yurt?

I shopped around in our area a bit and realized the yurt frame was going to be fairly affordable. Just the frame and all the parts needed to get the frame up might be less than $500.  If you look at my article on Log Cabins you will find near the bottom photo’s of my milling operations using the Alaskan Small Log Mill, my chain saw and the Beam Machine. I calculated from that one log I could make 128 10’x1″x2″ pieces. I would probably need a table saw or skill saw to make the 1×2 pieces from 2×18 planks. And at a cost of only about $10 in fuel and oil.

I’m not sure what an awning maker might charge to make the top section and side section but material is near $4 per yard. On this first yurt we will be cutting pieces from an old revival tent. This is some kind of rubberized canvas. A person could use the clickable calculator below to calculate the size of wedge shaped pieces of material needed for a roof piece. You would enter the slope distance and not the horizontal distance for the radius in this case along with the number of pieces. To figure the shape of the round edge simply use a string nailed at the apex, then with a pen tied to the end of the string mark the arc shape for both the outside and the sky light hole. Each piece could then be cut out and sewn/glued together. This could also be used to calculate the sizes for tin roof pieces.

The wood for the floor is a different story all together. I priced this at $2500. It could be done cheaper if rough cut by some local mill, maybe $1000 or so. I bought some tools to mill my own lumber. A used chainsaw, $250. Beam Machine chain saw attachment $50. Grandberg mill chainsaw attachment $200. We plan to mill all the wood for the yurt. Not counting the cost of the milling equipment we hope to have less than $500 into this yurt when finished.

Yurt kits go for $5000 to $8000 or more.  If you have the money, the kits are probably worth every penny, though I’m sure a bit overpriced.

I am wondering why the industries of the world do not mass produce yurts and offer them at rock bottom or at cost prices for the homeless around the globe. Or at least to missionaries, peace corps and for disaster relief. The yurt is the perfect temporary shelter for any location anywhere, they just need to be shipped. Its darned arrogant to think that because other peoples around the world can’t afford a modern home that they should have to live in card board boxes or homes made of scrounged parts or whatever. The existence of living in a yurt would be rich to many homeless peoples around the world. Churches around the globe should make these for their missionaries with donated materials. Churches should be the leader in getting this type of housing to people in 3rd world countries.

How about putting yurt on stilts in a flood prone area.  It is light weight and this would be easy to do. What about putting a yurt over water?  Sure, on stilts over water, would make an awesome lake cabin for lakes with well known maximum water levels.

A ladder could be added which goes from floor up to the sky light for added support, as well as providing a view from the peak of the yurt. Maybe even a great shooting position aye?

A 2nd floor could be added which would serve as a loft. In the above design which I lay out in this article  consider an inner 12′ diameter floor where the joist of this floor is 6 feet 6 inches off the main floor. This should give 5 to 6 to 7 feet of head room. 2 to 4 people could then sleep in the loft area. A ladder would be needed for loft access. It would need to be supported by some sturdy columns. These columns may need to descend through the floor to concrete piers and footers. Bracing may also be required on the columns.

Could a yurt be made from poles for the lattice works? I’m sure Mongolians used poles. I’d guess 1 to 3 inches in diameter tree’s and limbs could work if they are straight enough and don’t taper too much.

How about a bamboo yurt? Would river cane or fishing pole cane work for a very very small yurt? Or how about combining small river cane into chords which make up the yurt poles or sticks for the lattice.

Other variations on the yurt theme. For example if its a permanent yurt, many different things would work well for round, cylinder walls. Then the yurt wood top could be used as traditionally.

Earthen walls to include. Super Adobe, Adobe, Rammed Earth, Earth Bag, Earth Tube.

How about papercrete sprayed on the yurt frame? I’m not sure that I’d do the roof section that way, but for the wall lattice this method would work nicely, and provide some insulation. Papercrete has an R rating of 2R or 3R per inch of thickness. If you couldn’t stand to cover the nice wood lattice with papercrete then blocks could be made and stacked around the outside of the lattice as the wall covering. The roof covering could then drape down over the papercrete wall veneer. I sheet and some vapor barrier plastic could be between the lattice and the papercrete wall veneer. Other variations of wall veneering might be possible too, such as the earthen methods I listed above.

Verticle Log walls can be done using a variety of  methods.

Grain Silo walls.

Steel or metal frame instead of wood?  Any kind of scrap metal might work for this. Tac weld the frame where the lattice pieces cross.  Would make a frame way stronger than the wood yurt frame. Use angle iron for the roof for at least one direction in the lattice. Flat iron could be used for the sides. How about rebar? How about Metal pipe?  PVC or Plastic Pipe filled with grout or some other material to make it rigid? And as long as we are putting up metal frames, how about gunite or shotcrete? Plaster? of course metal lathe or chicken wire might be needed.  The yurt frame and structure and design could be made many different ways if one put his mind to it.

I was told at a Genghis Khan exhibit, where they had an authentic yurt on display, that it took 10 men 10 days and 200 sheep to make the cover for one yurt. If you are interested in felting yourself, look up felting machines on Ebay. Also one can hand felt with felting needles (not me). A felting machine resembles a sewing machine in appearance. Basically all animal hairs have joints. If you wet the hair and agitate it, the hairs align an interlock making felt. Wool, Angora, Mohair and other animal hairs can be felted. If the felt is thick enough its even water proof. It insulates really well.

The way the mongols made felt was to take a felt mat and add a layer of fresh hair to it, wet it, then roll it up like a rolled up carpet. Then they would tie it to a rope and drag it for miles behind horses. The new felt would then merge with the old felt.

Update on our yurt plans. We were first going to build Gary Tuck a friend of mine a yurt. We had decided it might go good next to a good sized pond on their place. The problem we were having was in keeping the cost down near $500 for the whole project. We have had found a way to do that but it required milling quit a few logs for the floor decking and structure. Not having time for that has postponed the whole project a year. However, Gary Tuck recently found a source for free 4’x8′ pallets. I also have a brother that can get me random sized pallets for free from his business. So we have new plan.

We can get used light poles from the power company for free. These are treated so they would make great post/piles. His pond’s water level usually drop 4 feet or so in summer. So we are now planning to construct using these post a platform/deck 1.5 feet off the ground at the lowest point and probably 3 feet off the water. It will extend maybe 4 feet over the water when the water is at normal full levels. We will put in the piles, then attach some 2×4 bracing to them. We will attach treated 4×4’s on top of the pile to run horizontally as the main structure for holding up the pallets. We will staple 6 mil plastic to the underside of the pallets. The pallets will lay on top of the 4×4’s and overhang a foot all the way around on the perimeter. The area under where the yurt will be placed will have used/recycled fiberglass batt insulation stuffed in that we will take from an abandoned mobile home. We will then nail down thin plywood sub floor on top of the pallets.

Using my chain saw I will cut the 2×4’s off some of the pallets to make 1.5’x1″x4″ flooring planks. We may floor the entire deck with this. Then sand it with a huge electric buffer/sander. Then water seal it. The area where the yurt will go however will need a 22’diameter additional flooring in a circle shape. We will mark this area and lay down some additional flooring and cut it to shape with a router. Again sand it and apply water seal. This will make a deck 28’x28′ leaving 6 feet on the water side for a porch/deck that overhangs the water 4′. There will be 3′ on each side of the yurt on the sides. And the yurt will be at the edge of the deck on the land side opposite the pond. The total cost in this may go slightly over $500 maybe even up to $750. We intend to mill the lattice framework from logs. And use an old revival tent to make sides for the yurt. The roof may still be a problem. I’m trying to talk Gary into roofing it with #10 cans used as shingles. Though I’d prefer a canvas roof if we can get that cheaply enough. If we can’t then the price will go up above $750 to who knows how much more, maybe $1500.

Recommended Books
Build a Yurt
Len Charney
Publisher Unknown

Please Visit Christian Forums

Earthen Construction

WANTED! Comments. Not wanted! Compliments. If you want your comment to be accepted first you must not be a spammer that WordPress recognizes and second you need to comment specifically on some of the article’s specific material or facts.

The Survival Pod Cast
Off Grid Net


Earth Ship Illistration

The Survival Pod Cast
Off Grid Net

  • Adobe
  • Hybrid-Adobe (Uses Cement and Paper or other added materials in the mix, instead of straw.)
  • Rammed Earth
  • Rammed Block
  • Earth Bag
  • Earth Tube
  • Cob
  • Earth Ship (Rammed Tire)
  • Earth Covered Roofs (Sod)
  • Dirt floors
  • Gabion

You may want to read as a prerequisite Green? my blog post on the green building trend.

This is some images of an earth sheltered design. The infil between columns in this design is earthbag, though it might be rammed block, cinder block, log, concrete and other methods. Warning this is a concept that has not been fully engineered.

This slideshow requires JavaScript.

The above list all the types of earthen construction of which I have read about thus far.  What type of earth? It depends, but most of the methods call for a proportional mixture of clay to sand. All would be without loam, which is the more decayed plant like material.  Gravel and stones would not make up much of a mixture if any.

Earth may need to be stabilized. This means that it would need to be made stronger, glued together better and so that it can support more compression or weight without falling apart or mashing. This also helps to prevent cracking. Stabilizers add abrasion resistance and erosional resistance.

Wheat straw (which can be found sold as fodder or bedding for horse stalls, at the time of this writing for $4.50 a bale, bale being 8″x16″x32″) would be the most famous choice as a stabilizer in some types such as adobe or cob. Cement would be another stabilizer for types such as rammed earth or rammed block.  Lime might be another, for example in “Roman Cement” lime is mixed with clay. Fly Ash (ash from burned coal or coke) could be another as well.  Asphalt yet another.  And there are other types of stabilizers that I most likely have not mentioned in this article. Much of the advancement in stabilization of earth has come from the civil engineering in road building in recent years.

The exact construction of a given type would be shaped by the humidity, rainfall, snowfall, ice and freezing for the location of the structure.  I suppose the driest most arid climates would be most suited, however cob has been used in very wet climates such as the British Ilse. If the designer applies enough thought he may be able to use any of the earthen methods in virtually any climate.  The equation is simple. The more wind, rain, moisture that is present the more stabilized and protected the earthen structure must be made to be. None of the earthen structures are as durable as baked clay bricks or concrete.

Why use earthen methods of construction?

  1. Thermal mass properties. (It stores heat and cold well, which is good for the energy efficiency of a dwelling.)
  2. Economics (It could be near dirt cheap all depending on the situation)
  3. Readily available (Can be gathered from the building site itself or from nearby)
  4. You have access to very cheap or near free or maybe even free labor?
  5. Playing in the mud is fun? Well for boys, of course men have pricier toys and projects.
  6. Maybe you have a taste for military field style construction?

Adobe would be made from sun dried bricks of mud and straw. The mud should have the proper proportions of sand and clay. Too much clay and it shrinks and cracks easily. Too much sand and it falls apart. Adobe walls are usually about a foot and a half thick. Bricks are made to be about 40 lbs each so that they may be easily carried.  Cob is very similar to adobe except that it is not sun dried and cures more like concrete. Cob walls are about 1.5 feet thick as well and are built from the ground up by packing globs of the cob mixture onto the top of the construction over and over until it is completed. Thick paddles are used to tamp and pack the outside of the wall as you go up.  Earth bag, earth tube and Earth Ship all use normal loose soils. Ratio of sand to clay is not as critical. It is packed in place in a near dry state. It is packed into tires with a sledge hammer. Soil is shoveled into polypropylene earth bags, or long earth tubes. (Recently at a company called “White Bag Company” in North Little Rock, Arkansas I purchased 1000 polypro bags 14″x22″ in size for $160 UV Rating of 1500hours, UV rating means number of hours in full sun that the bags will take without falling apart, and yes they will if not covered in some fashion such as by plaster or earth or mud.) In the case of tubes, the tubes are run in layers coiled in a circular fashion. For earth bag and earth tube walls barbed wire is used between layers for reinforcement.Earth bags are usually staggered like bricks.

Hybrid-Adobe uses adobe mix without the straw, but adds other materials such as paper, cement, glass shards etc. Not much to say here, but I will direct you to a web site–Hybrid Adobe dot com And they have a book which I have yet to buy and read, so I can’t really recommend it just yet.

Rammed earth is stabilized with cement or possibly lime and/or fly ash. If cement it is near 10% mixture of cement to earth. Rammed earth is moistened to a bread dough consistency then packed into forms that resemble concrete forms. Rammed blocks are the same but use a machine to press the blocks. Fernco Metal has several block pressing machines.  The cheapest is $1200 and is manually operated. Blocks are similar in size and shape to adobe blocks. Rammed blocks would be stronger and more stable than adobe. Rammed earth does not include straw.

Earth covered roofs are roofs with strong frame structure supporting them, near 180 lbs per square foot strong. These roofs can be steep but need to have at least a slight slope. This next list shows the layers in an earth roof top to bottom.

  • Sod (Grass)
  • 6 inches of soil
  • Sand
  • Gravel
  • Old used carpets to protect water proof membrane.
  • Water proof membrane such as a 40 mil pond liner.
  • Old used carpets to protect water proof membrane.
  • 4 to 6 inches of Styrofoam insulation.
  • Tar paper
  • Plywood or planking.
  • Structural frame (roof support beams, rafters, joist)

I felt I at least needed to mention a gabion. A gabion is a box, cage container which is filled with loose earth or rock. The gabion container itself merely acts as a retainer.  Metal wire boxes might be used. Bamboo, or wicker containers have been used in the past. Most people have noticed these as hex poultry fence wire made into boxes and filled with fairly large stones. I have seen this used as retaining walls and privacy walls, and for erosion control. The Earthship wall is basically as set of gabion bricks where a tire is used as the “cage” to hold the earth. In earth bag the bag or tube acts as the gabion.

Dirt floors are made by layering and tamping. Gravel is used below for good drainage, then sand, then earth. The stabilization of the earth is increased the closer you get to the surface. Finally the floor can be waxed with bees wax. Also straw may be used in the layers for reinforcement.

Walls are plastered with either a cement type plaster, stucco or a more breathable lime plaster, and possibly in some cases a mud plaster.  Cement plaster can trap moisture between the plaster and the wall and should be used carefully. Plasters can be reinforced with fibers or animal hairs. A lath may be needed to hold the plaster in place or for reinforcement of the plaster. A lath is a rough grid like surface by which the plaster can adhere too. This can be chicken wire or specially made lath. In times gone by it could have been wooden lath. In waddle and dob it was made from thin branches woven together.

Now I will talk about some of the book resources available. Most of the adobe books I found (and there are quite a few on adobe) seemed to be very good all the way around. One that I found was on the repair or restoration of old adobe churches and homes. The one book on Cob I found was very good and covered earth floors and a Cob bread and pizza oven. Rob Roy has a book called “Earth Covered Shelter” which is a must have. I have seen one on earth bag listed below but have not bought it yet, though it looks very nice and comprehensive. There are 3 books on Earth Ships written by a hippie environmentalist architect. Those houses are architecturally sound and are simple to construct. However I feel that the tire wall thing is kind of risky in any climate but a very arid desert like climate, especially the way the author uses the ground itself in places and merely plasters over the ground. I have the engineering text book on Soils and Foundations and have so far found it to be invaluable source of general info, even if you don’t work the formulas, as with many college engineering level books. It goes a long way in letting you understand exactly what kind of dirt you are dealing with.

However after much thought I have found ways in which the tire walls could be constructed in very wet climates and be made to be waterproof. This adds to the construction time, cost and complexity. For example the walls would have to extend all the way to the grade over the entire U module, and the base of the walls would need to be above grade. You would need very good gravel drainage, possibly a pond liner and french drains to protect the wall and berm from water penetration.  Also something like a cavity wall could be constructed between the tire walls and the berm or embankment (hill side). A cavity wall is merely two walls with some space between them.

None the less I personally would consider using tire walls for any non living space such as storage, shop space, garage space, barns, sheds, animal shelters, retaining walls etc. in wet climates. In wet climates for living spaces I would go with 2 to 3 foot thick walls made of Brick, Block, Rock, Concrete, Earthen or Earthen core with any of the other methods as a box or perimeter or surface to contain the earth core. Also remember that with a wall of this size the footing will need to be very huge, maybe 2 feet deep and 8 feet wide.  The U shape of the Earth Ship module can be more square in shape but this might reduce the strength of the design somewhat. Reinforcement bar may need to be added to strengthen the design so that the U Shape for non-tire walls would be comparably strong to that of the tire walls.

One particularly interesting document I found was produced for the Peace Corp. It is called “Handbook for building homes of earth”. It goes into some very good detail on soils and stabilization of soils. It goes into great detail in telling you how to determine clay content. It covers how to test compressive strength. How to test for abrasion resistance and erosional resistance with a spraying test.  I found this as a PDF on the web, but also it can be bought as a book. Earth adobe blocks or cob walls end up having about a 150 to 200 psi strength. Rammed blocks maybe 350 to 400 psi strength. Compare that to concrete block of 2000 psi, or baked brick of 4000 psi, or concrete at 6000 psi or granite stone at 15,000 psi or steel at 25,000 psi. Wood from the top of the post pressing downward is about 10,000 psi. Soils can be any psi up to hundreds of psi. Usual soil strength might be 50 to 70psi. Of course moisture in soil changes a lot and makes a huge difference. More moisture typically reduces compression strength. Earth walls are wide however which means they spread more roof weight over a larger area.   An earth wall that is 1.5 feet wide will support nearly 43,000 lbs per linear foot. A concrete block wall 8 inches thick will support 191,000 lbs per linear foot. An earthship tire wall (3 foot thick) would support 100,000 lbs per linear foot or more. So you can see that the earthen walls, though being the weakest in pounds per square inch, do have strength for supporting roof structures.

By the way would anyone know what the EPA thinks about using trash or tires as a construction material? EPA will mandate strict disposal of waste tires. I think though if the tires were used in construction they then become a construction material and not waste. And a last note, remember that anything slightly underground or earthen in wet, humid climates may sweat, or collect dew or otherwise be moist. Therefore in living spaces or environmentally controlled spaces de-humidification would be necessary. The good news is that the energy cost for de-humidification will be half that of the standard A/C and you might get grey water which can water plants or even drinking quality water from some dehumidifiers. Eco Blue is one such dehumidifier. Passive dehumidification can be achieved by setting containers of rock salt here and there. The rock salt can be cooked to remove moisture and then reused. Damprid sells some rock salt type dehumidification products that let water in and will not let it escape back out.

About earth roofs and berms: One way to protect from water penetration is pond liner. The other is Bentonite or other clay layer. You can get clay in sheets I think. If you are really serious use clay on top of the pond liner. Or clay directly beneath and on top of a pond liner. Clay can actually self heal if it gets a small hole in it.

Recommended Books
Handbook for Building Homes of Earth

Earthship Volume I

Earthship Volume II

Earthship Volume III

Building with Cob

Adobe Conservation A Preservation Handbook

Earth Sheltered Houses
Rob Roy

Earthbag Building
Donald Kiffmeyer

Soils and Foundations
Cheng Liu, Jack B. Evettr

Also see my web sites larrydgray.net and arksoft.org

Please Visit Christian Forums


WANTED! Comments. Not wanted! Compliments. If you want your comment to be accepted first you must not be a spammer that WordPress recognizes and second you need to comment specifically on some of the article’s specific material or facts.

The Survival Pod Cast
Off Grid Net


What is Green and what does it mean? Of course it is a color, in the modern context it means “Earth Biosphere Friendly”. Green has meant in the past “Money”.  It has also meant “New, Fresh and Unskilled”.  And how about “Nausea” or “Extreme Fear”? Maybe it means saving the world from “Global warming” to some. To me it means “Energy Efficiency” in architectural design of buildings and “Saving Money” each month on energy bills. It can mean reduction of monthly living cost.  It can mean a measure of independence gained. It can mean measure of sustainability. But not without a cost. Not without investment.

I have looked into various types of green building.  Earth, Straw, Insulated Concrete Forms, Masonry and Concrete, to name a few. Underground, Earth Covered and Passive Solar shelters, to name architectural designs. Some energy efficiency features are “Passive”, meaning they require no effort and no energy consumption. Others are the opposite, “Active”.   Some features may be operated manually, while others automatically.

Warning this is a concept design that has not been fully engineered.

This slideshow requires JavaScript.

Is dirt really “Dirt Cheap”?  Maybe, maybe not.  Earthen structures may require more labor, however less skilled labor and less complex design. Some types of earth structures and straw bale structures are susceptible to damage from moisture and water more readily than conventional materials. Proper waterproofing will raise construction cost and complicate the design. Automation control will increase cost and energy use in any active systems. Green features will increase the initial cost, overall cost and possibly complicate the design.

How much extra cost there are will depend on the individual builder, the location, the situation, the feature and the day and time. How soon energy efficient features will pay for themselves is highly situational dependent. Obviously on the North American continent these types of homes pay off more quickly in the arid Southwest than anywhere else. But one thing is for sure. A dwelling can be made to be far more energy efficient than the typical conventional dwelling. Monthly energy use can be reduced. In the end its up to the individual to decide if it is worth it or not

There are about 4 factors that make a dwelling more energy efficient than the traditional insulated box (a mere refrigeration unit).

  1. Use the sun a lot more for heating in winter.
  2. Use the earth a lot more for heating in winter and especially for cooling in summer.
  3. Use heavy insulation in the ceiling area.
  4. Use thermal mass as a storage medium for heat or lack of heat(cold). (This is the most important feature.)

Thermal mass is to heat what the battery is for electricity and similarly it is charged and discharged. The good news is that unlike chemical batteries for electricity thermal mass usually doesn’t go bad and need replacement.  Thermal mass would basically be any dense material. Metals work best but are are very expensive for this purpose.  Water works great. Earth, concrete, brick and stone are more reasonable choices. Where do you put this thermal mass? Mainly the walls, very thick walls. Could also be in the roof as in a roof pond. Or barrels of water placed here and there.  The floor could serve as thermal mass as well.

You can do the math. One BTU is the heat needed to raise one pound of water one degree Fahrenheit. 100 gallons of water (8 pounds per gallon) raised 1 degree is roughly 800 BTU.  In space solar intensity is about 450 BTU per square foot per hour. On earth when the sun is shinning bright on a surface which is perpendicular to the sun near the noon hours a surface will receive about 350 BTU/hr. This varies and can be much less in winter as low as 100-250 BTU/hr maximum for during the day.  But lets say you have a surface that is 10×10 or 100 ft2 and it is receiving 100 BTU/hr then it gains 10,000 BTU in that one hour.  To raise one cubic foot of air one degree F, you need roughly 0.018 BTU.    A 10 foot by 10 foot by 10 foot area of air is 1000 cubic feet. Raise that area one degree and that space has gained 18 BTU. A typical window A/C Unit might be rated for 5000 BTU/hour.  A typical home heat pump might be rated for 1 ton (12,000 BTU/hr/ton).  A kerosene floor shop heater might be rated at 150,000 BTU/hr. The question that I have is, how fast would a given type of thermal mass absorb or radiate heat? I don’t know the figures here, but I assume that would be based on the specific gravity (density) of the material. How much total absorption would also be based on the surface area of the material or its container.

There is more to the overall design than this. Auxiliary heat and cold air may still be needed. De-humidification may also be needed.  Vents, and Sky lights may have some positive effects if used properly. Extra shading, operable shutters, curtains, and movable insulation may be needed. Reflectors may help with solar gain. And in the end some of this may require manual adjustments to be economically feasible. Automation is not without additional cost.

Now, on a sad note,  our system for getting green houses(or any houses) built and insured may not support all of the green features, or even the entire project.  Building Codes may restrict what can be done if your building site is not located remotely where there would be no or little regulation.  Insurance may not cover extra cost of the extra features.  The market may not accept the extra features. And banks may not loan on these extra features.  Great system huh? Its against energy efficiency! Not by design however. I feel that it has simply evolved that way.

In conclusion I say that I feel it is worth it to consider every energy saving feature that could possibly be available to the home owner and even worth reconsidering upgrades over time. If you really strongly desire a truly energy efficient home, build it with cash as you go. You may have to  go to some extremes to be able to do this, but in the end any savings you might achieve from owner building and using cash as you go will more than make up for the extra cost of the green features. This also means that as you build it and begin to live in it, you get savings in your pocket immediately. It pays off right away.  As an investment that you can liquidate, the picture might not be so pretty. A home that is too far from conventional design and from what the general market expects may be hard or impossible to sell or be sold at a loss.  That said I still feel that it is worth considering as long as you use cash and not credit for the construction. For example it could always be rented and with no debt against it, it would mean low overhead and good income.

Oh and my opinion when it comes to power production and the green scene? I am for Solar, Wind, Hydro and Nuclear, and against all other forms of commercial power production except in emergencies or periods of peak demand. I feel that its a great waste to use coal or gas for power production. And nuclear has actually proven to be very safe. Sure we have this depleted uranium problem. But the truth of the mater is that our transportation system is far more destructive to human life and the environment than nuclear power will ever be and you don’t see the environmentalist winning about it? They drive their cars don’t they! Nuclear as far as I’m concerned is a green power technology.  The demand for power in the world is only going up and nuclear is the only one that can fit the bill. Fusion power is just around the corner though. I hope to see that in my lifetime.

Great, just as I say Nuclear is a green power tech Japan has an earth quake and tsunami which washes out a nuke plant. The worst of what happened was the spent fuel pools being washed. Generators that power pumps went offline and cause cooling water to stop flowing. This caused the water in the pools to boil dry. Partial meltdown of reactors and spent fuel has occurred. The reactors are designed to contain a full meltdown. They are designed to spread out molten fuel to a degree in which it either cools down completely or enough so that it doesn’t burn through the concrete and deeper into the earth. The spent fuel pools are not under this containment. My question is why not? I would guess because of expense. Lets hope this incident does not do a lot of damage. The media has been saying that radiation has been found in water, fish, milk etc. But this isn’t exactly right. Its contamination, which causes radiation. If something is hit with radiation and the radiation is removed then that thing does not emit radiation and is not radioactive. Unless it is contaminated with radioactive particles. Radioactive particles move around via air and water. Contamination is like a radioactive dust. So they are not detecting “radiation” in food and water but contamination which emits radiation. Even with this scare if you looked into it, you would see that the nuclear industry has a great record for safety. I am thankful that concerned people monitor it closely. We just need to spread this kind of concern to everything else in life.

Recommended Books
Passive Solar Energy Book

Passive Solar Construction Handbook

Also see my web sites larrydgray.net and arksoft.org