Dome-vault; "high tunnel" for winter building

In our Safe Haven Villages meeting Friday, I got a lot of great input for the building of our home.

Based on that and subsequent input, here's a sketch of the side view of the design I'm presently favoring.

The earth bag walls go straight up with periodic buttresses along the horizontal length. At 8 feet up will be the floor joists, then the straight earth bag walls will end up another two feet. At that point will start the 10-foot radius concrete dome, which will have insulation around it. So the parabolic, catenary arch has been nixed. We're still sticking with the slight arch as the house goes east and west, concave to the north to help the house resist the backfill. Torg also recommended having anchors out in the back-fill, tied to the earth bag wall. The east and west ends of the house will still be rounded. Torg pointed out that having the north wall convex to the backfill would tend to wall failure, whereas having the north side concave to the backfill would tend to the earth packing the wall tighter -- the arch principle.

Torg suggested that I not use any cement in the earth bags, saying that cement will crack in the event of an earthquake or settling, whereas rammed earth in the earth bags will just “reanneal”.


Regarding most of our building time being through the winder, per the 180-days provided by the 1031 roll-over, John Day suggested that I use a "high tunnel" cover over the site. This could entail using pvc pipe with plastic overlaid, and some kind of heater inside, e.g. propane, augmented with a rocket stove. This would enable us to build through freezing temperatures outside.

I'm wondering if this is a plausible approach. How much PVC pipe and plastic will that require; and how hard will that temporary shelter be to build? How much energy will it take to heat to prevent freezing?

Another question I have regards storage. What would be the best way to store my building supplies and other things while we are building?

Torg said that even with the compact earth, not using cement, we would want to keep the structure above freezing so that the wetted earth can properly dry.

In addition to his other skills, Torg also is an architect (not presently licensed in Utah). He said he could draw up our plans, including the electrical, plumbing (including rainwater capture, cisterns, and compost tank for the main restroom), and engineering aspects; and he has an associate who is a licensed Engineer in Utah, who could then sign off on the plans.

I'll need to decide what appliances and how many will be AC versus DC for each room, to determine how many lines to run to that room. In earth bag construction, the wiring and plumbing is laid down as you go. You don't want to run conduit, because the metal tends to bend from the compacting process.

One of the things the community is talking about getting right away is a track hoe for excavation, road building, back filling etc. By the time we rent a track hoe for the various homes we want to build on the site, we will have paid for the track hoe; and we can get our money back out of the track hoe when we're done.

That sounds nice, except that up front we are strapped for cash, so I would rather rent at first. Aaron N. knows two people with track hoes.

Forms & guides for 20-foot wide parabolic earth bag vault

Below is some correspondence with Owen Geiger, professional earth bag builder. Also, near the bottom, is some earlier correspondence in which I mull over the impossibility of building an earth bag home for my family of 6 in just one month in the Spring (2010) after the freezing weather is behind us; then realize that I'll have to plan on purchasing the materials, then build.

In the most recent corresdence (near the top), Owen's comments, received the morning after I posted this, are indicated in red.


After writing the below, I bumped into the Owen-Torg correspondence regarding Nubian technique for building Catenary arches using stabilized earth blocks.

I found the following page http://www.earth-auroville.com/index.php?nav=menu&pg=earthauroville&id1=4 which has a lot of photos that resemble the paramecium plan we're contemplating.


In particular, here's a photo of the Earth Institute which has a fair resemblance to what our finished home might look like.


except ours would be made of earth bags and would not be straight but curved along its length/ and ours would not have square walls on the exterior, and the ends of our vault would be rounded like a half-beehive.

Perhaps we could use the ends as the Nubian form and move forward from there first.

Compressed earth block (CEB) vaults: These vaults require skilled, experienced masons. It's not something you can learn overnight. Building CEB vaults on a curved house would be very tricky. Plus, they are better suited to mild climates. You want an insulated roof for Utah. Note: the current design lacks adequate space for insulation.

Instead of CEB vaults, I recommend ferro-cement or nylon cement vaults with about R-40 insulation: http://www.angelfire.com/in2/manythings/TEXT/NYLON-CEMENT.htm (tech info near bottom of article) This makes it relatively simple to add dormer vaults, eyebrows over windows, curved end walls, etc. using almost any curve you want. At this point, this looks like the best 2nd story system for you.

Make a 6" reinforced concrete bond beam for floor joitss to sit on. Embed upright sections of rebar for the vault.

It's best to make rebar trusses: http://www.earthbagbuilding.com/projects/shop.htm (see last 3 photos)

Bend the rebar around a jig so they're all the same size and shape. Then tie these long, curved trusses to the short pieces in your bond beam. Then add perpendicular rebar and mesh.

Here are some interesting scaffolding pictures (no forms, just guides [possible with brick]):






And here's a couple of photos demonstrating the strength of the catenary arch.






===============

Hi Owen,

Yes, I would appreciate a summary of recommendations.
Okay, let's decide on the basic building system first.

We plan on using a ~10% concrete mix in our external bags and that they will be hardening as we go up, no more than two or three courses in a day.

Would you agree that with 10% concrete mix, that the first eight feet, which barely tip inward, will be strong enough to support the beams for the solarium roof/deck and the second floor?
Yes, no problem.

How far apart should these beams be? How big (e.g. minimum) should they be? Will they need any reinforcement?
I think you're referring to floor joists. These are typically TJI joists set 16" apart. You can go 20' span with certain brands/models of 12" of TJIs. Are you still planning a block or CEB wall down the length of the house? This means you could use 10" TJIs and would eliminate the awkward flex in 20' spans.

I've got a question. Will the bags need to be protected from rain, once they are in place, before they are sprayed and finished on the exterior?
Yes. You'll need to protect them from sunlight with tarps until you can get a coat of plaster on, even though rain is not a big concern (because they're stabilized). That's why I recommended spraying gunnite in stages. You don't want lots of tarps flapping around for months.

We were planning on 20-inch bags from Cal-Earth for the vault. Will that be thick enough, or should we use thicker bags. Does Cal-Earth make anything thicker than 20 inches?
Not sure what sizes they have. 20" is a good size.

I'm thinking that going up 8 feet that we'll be pretty much okay without much reinforcement, form-wise, for the first floor. Then maybe we could go ahead and install the second floor to stand on and put forms on for going up higher from there on the exterior walls.
That sounds good. We just need to work out the details on the 2nd story forms and building method.

What do you think about Tim's suggestion to build the interior walls as we go up, to help support the exterior walls?
Yes. This is a good way. You can overlap the corners so they interlock.

Sterling


----- Original Message -----
From: Owen Geiger
To: Sterling D. Allan
Sent: Thursday, November 19, 2009 6:15 PM


Hi Sterling,

It all depends on the details: distance between supporting walls, what the supporting walls are made of (earthbag?), slope/shape of parabola, stabilized or unstabilized soil, how many guides, how strong the guides are, etc.

It sounds like a lot of guesswork to me. You could get up to 8 feet high and suddenly the walls start to lean and sag between support walls. And then what do you do? You'd have to tear everything apart and start over. It doesn't sound like a good plan to me.

Khalili is the only one who's done this, and he used forms throughout. And Kelly thinks he used earthbags only so far up and then poured concrete on top. The vaulted school in the Philippines used concrete on top, too. http://www.earthbagbuilding.com/projects/school.htm

Kelly Hart's elliptical dome collapsed, and the Om Dome (world's largest earthbag dome) started to lean in and had to be rebuilt. These were built by talented people, but they misjudged what can happen with tons of weight teetering in the air.
http://www.earthbagbuilding.com/projects/omdome.htm

So I still think it's possible, but all the details have to be worked out very carefully. And I don't know anyone who can give you 100% assurance on this -- not me or anyone else, because it hasn't been done before.

I can write a summary of recommendations if you'd like.

Owen

--- On Thu, 11/19/09, Sterling D. Allan wrote:



[...]:

----- Original Message -----
From: "Tim Hall"
To: "Sterling D. Allan"
Sent: Wednesday, November 18, 2009 10:03 PM
Subject: Re: 180 days over end of April; Re: Parabolic Arch better; change convex to the south


Aloha Sterling,
As far as building forms we are going to build interior walls that
will hold wall roof in place, you have at least four walls from front
to rear. we only go no more than three rows of bags per day if we are
lucky. we only need guides .

Aloha Tim



----- Original Message -----
From: Owen Geiger
To: Sterling D. Allan
Sent: Wednesday, November 18, 2009 5:16 PM
Subject: Re: 180 days over end of April; Re: Parabolic Arch better; change convex to the south


Hi Stirling,

Just to restate the essentials, you definitely need a form, and it must be very strong. You'll have tons of weight overhead. And yes, do it in sections about 4-8' long and slide the form along.

Here's Kelly Hart's advice on vaults: www.earthbagbuilding.com/faqs/shape.htm#vaults

He cautions against going over 8' wide! I'm convinced you can go much larger, but again, you have to be very careful. It may seem simple in principle until you're right in the middle of it. (Sort of like mountain climbing, where you tell yourself "just keep climbing." But you eventually reach a point where you're in over your head.)

Domes lean into themselves, so they're very stable. Vaults have nothing to lean on and will just suddenly fall over. And, of course, they won't care if someone is standing underneath.

Again, no one has done what you're attempting [...]. Please do more research and, even better, build a demo vault.

Concrete block: Sure, this is an option, but it looks ugly and has huge environmental cost. Anything with high thermal mass will work. Why not introduce something that's natural and beautiful. Ex: you'll never tire of looking at natural patterns/textures created by adobe, pressed earth block or stone.

Owen

--- On Wed, 11/18/09, Sterling D. Allan wrote:


From: Sterling D. Allan
Subject: Re: 180 days over end of April; Re: Parabolic Arch better; change convex to the south
To: "Owen Geiger" , "Tim Hall" , "Safe Haven Villages admin egroup"
Date: Wednesday, November 18, 2009, 2:26 PM


Hi Owen & Tim & SHV people,

Now that the reality of the 180-day thing has set in, and I'm adjusted to the idea that I'll have to purchase my supplies first and store them, then build, I'm not quite so stressed about being under the gun to finish the house so soon.

We'll have some community funds (hopefully) that I can draw from toward repaying the money I'll be paying up front for the community land.

So back to the questions regarding the Paramecium house design.

I can see how a wall in its earlier stages would not need to be supported, but the steeper the angle goes toward the top, the more the bags are going to want to slough off, and the more the walls are going to want to tip over -- until they meet at the top where they can lean into one another.

I'm wondering how much and how I'll need to provide forms against which the rising walls can lean.

I can see how the bags would not slough off in a beehive shape structure -- I've built several snow forts that way -- but I don't see how the bags would not slough of near the top of the vault construction.

One way to do this would be to complete the arch on one end, over a form, then move that form forward, and complete another arch section. That would prevent longer sections of bag and longer sections of barbed wire; and it would require barbed wire lengths to protrude from the unfinished courses, to tie in to the next section. If these hung down into the inside, then they wouldn't get in the way of spraying the exterior in stages to protect the bags from UV deterioration; and it would enable tarp to cover the unfinished portions without getting shredded by the barbed wire.

Another way to do it would be to build a stick framework over which to build the vault; but that would take a lot of wood. Perhaps I could gather scrap wood from a dilapidated barn or something, then use that as firewood when I'm done.

Either way, I'm wondering how frequent the support needs to be. Maybe as I go up, I could have sheets of plywood that I set in place during the tamping down of the bags, then I can pull those out and move them up for the next course. I would think that after tamping, the slough tendency would be gone, except near the very top. Also, I'm wondering about how much leeway we have in the smoothness of the interior and exterior surfaces. If the plywood is overlapping, so there is a 1/2 - 3/4 inch line, can that be covered by the chink-fill stage? Or is it best to avoid that?

Also, regarding the vertical wall through the middle of the arch in the West end of the home, I would think it would be easier to just make that out of cinderblock. I'm open to using conventional materials in some places. This home will be a hybrid of old, new, future technologies.

Your thoughts?

Sterling


----- Original Message -----
From: Sterling D. Allan
To: Owen Geiger ; Tim Hall ; Safe Haven Villages admin egroup
Sent: Monday, November 16, 2009 8:14 AM
Subject: 180 days over end of April; Re: Parabolic Arch better; change convex to the south


Hi Owen,

Thanks for the input.

When you suggest a wood form for the vault during construction, maybe you can elaborate what that would entail. How frequent would the support need to be? Are you talking a form that would fill the entire interior during construction, or one that would be moved along, completing from one end to the other (using rice bags rather than long length tubes from Cal-Earth)?

As for spraying the walls as we go, what kind of company am I looking for? You're not talking shotcrete are you?

As for the middle, straight wall, isn't the compressed earth block (CEB) similar to concrete forms except that with concrete you get to have anchors between the forms which you later break off the ends that protrude from the concrete. Wouldn't that be a herculean challenge to create a form that tall and wide with no anchor between. I've not studied the earth CEB method.

The thing that has me most nervous about all this is the very shore time we have to work. I had thought that we had 45 days from closing to identify a property, then 180 days after that to finish spending the money for the 1031 exchange. However, Susan informs me that we have 180 days from closing (Oct. 30) to spend the money; which means we have until the end of April; and in Utah, early April is still hits intermittent freezing; so with building season starting with a few days in March, we would barely have a month of time to launch this Earth Bag construction. During the freezing season we could do the permitting, well-digging (if we go that route), excavation, doorway and window form building, form building.

I'm just not comfortable with the idea of buying everything before building and hoping we have enough, and not having those funds to draw on for the labor help we'll need.

And we're attempting a scale that pushes the envelope for this type of construction which even in its more tried form has but barely penetrated into Utah. The bureaucratic hoops could be daunting as well.

The learning curve for me is huge too. I'm venturing into all kinds of unknown territory:
- earthbag is new to me as of 1.5 months ago
- rainwater capture: I haven't yet looked into the particulars
- bottle/can walls: I haven't yet looked into the particulars
- earth floor: barely know about it
- earth bag plumbing and electricity: barely know about it
- earth home insulation and waterproofing: barely know

I should have my head fully wrapped around these things in order to properly design the home, which is one of the first things that needs to be done.

I can't help but think that we're not being realistic. We're trying to do too much in too short a period of time.

I'm thinking it might be best to shift to something less exotic.

Sterling

----- Original Message -----
From: Owen Geiger
To: Sterling D. Allan
Sent: Monday, November 16, 2009 2:09 AM
Subject: Re: Parabolic Arch better; change convex to the south


Hi Sterling,

I thought you were going to use a wood form to build the vault. Now it sounds like you're going to use a rope guide to line up each course. You definitely need a wood form or the walls will fall over during construction. Vaults are very tricky, even small ones. You're attempting to build possibly the largest earthbag vault in the world... use extreme caution.

Interior 12" wall: Narrow earthbag walls are not very stable during construction. I recommend adobe or compressed earth block (CEB) for this wall. This will also produce a straighter, nicer looking wall that won't need plaster.

Curving the house toward the sun is the best, I agree.

Also, create extra room at the top of the stairs, in the bathtub, etc. People need adequate space to feel comfortable.

I'd start looking for a company who can spray the earthbag walls. This will greatly speed things up. The best way is to spray the exterior in stages so you don't have to keep everything tarped. (Tarps want to blow away in the wind.)

Owen

2-floor Paramecium House Plans with Split Saircase

We've been working hard to come up with a plausible floor plan.

The Hot Dog House plan wasn't much of a hit. We didn't really like it either. Sometimes when going for green, pride is put on the shelf for practicality or for the environment (hopefully for both). But the Hot Dog house was not practical.

Susan was worried about how hard it would be to keep those beehive shapes warm in the winter. So she set about to come up with more of an earthship design (usually done with rammed-earth tires), but with earth bags instead.

She's got a floor plan designing software program, and this is what she came up with on her third version within our input along the way.



I just had a few modifications to make on that, and it turned out that this excercise came in very useful as you will see below.



A couple of days prior, I had a phone chat with Tim Hall, the Earthbag builder in Hawaii, who has been providing a lot of great input for us. He wasn't very excited about the square plan, thinking it was too conventional, and that it wouldn't really work very well with Earth bags.

I addressed the concern about how hard it would be to keep an earth bag home warm in the winter. Yes, there is nearly 2 feet of thermal mass in the walls, but usually you have to go 4 feet in the soil to get past the frost line. Soil isn't a very good insulator, but it's a great thermal mass flywheel. But without insulation, I would think that it would tend to reflect an average of inside and outside temperatures over a week-long period of time, or more. So if it's really cold out, that cold is not only going to penetrate, but it's going to sap the warmth out of the home. If it's insulated, though, against outside temperatures, and tied into the below-4-feet temp of the earth, then it would be great for its thermal flywheel capability, maintaining a comfortable average temperature, augmented by the solar gain to offset the winter cold.

Anyway, he encouraged me to come up with a hybrid design that combines Susan's floor plan with the vault earth bag design, but to go with two floors, and with a 20-foot width and height of the vault.

My first step was to make a revision to Susan's design, then apply that to the two story vault.

Here's what I came up with this morning, with input from Cheri.



It's not drawn to scale. It started as a very rough sketch that I planned to replace with a more carefully drawn version. But the longer I worked on it, the less inclined I was to re-draw it. The second floor would only be about two feet more narrow than the first floor at it's base, then would more rapidly curve to the apex of the parabola shape. I estimate the total square footage as around 2500 ft2. The first floor is around 1700 ft2.


We found a design of a split staircase online that we really liked to pattern in our living room. One section going to the kids area, and the other to the storage over the garage.

We like this floor plan a lot, especially the split stairway in the living room, the high ceilings in the living room and master bedroom, how things are grouped well together, the master bath & walk-in closet design that we liked so much in our Ephraim home; the reading loft with spiral staircase in the master bedroom, the playroom balcony that our kids love at my parent's house. The taller structure would enable us to put solar thermal and PV panels along the second floor with a walk way over the first floor solarium so we can brush the snow off the panels and give them a wash occasionally in the summer. The eutectic salts rack to the right of the solarium would help keep that room warm at night. This plan would work for us.

Cheri as a bit reluctant to have two doors to the outside from the second floor, considering teenage escape tendencies (once the kids get older). But I figure that teens will find ways to escape anyway (code requires egress), and I'd prefer to go for the trust deterrent than the cage.

Owen Geiger thought that a 20-foot vault would be a stretch for Earthbag technology, and he wondered how we would move forms (guides) that big along. I'm thinking that if the interior walls that are also earth bag are laid at the same time, that they can help hold things together until the arch is completed.

Tim also discouraged me from relying on rainwater harvesting. Given issues of 1) potential nuclear events and fallout, 2) chem trail muckity muck, 3) pollution from the 4-corners coal plant (~300 miles away); he thinks it would be best to get the potable water from a well, pumped by renewable energy.

Susan's going to work up a new set of plans based on this Paramecium design. She might not be able to put the curve into it, but it will give enough guidance to an architect who can do the plans more precisely once we settle on the design.

Keep the great input coming. We appreciate all the guidance we've been getting.

What a ride!

Revised House Plans & "Hot Dog House" Sketch

Hi Folks,

First, I changed the wording on my house page at PESWiki under Renewable Energy to "In addition to solar and wind, we hope to do some beta testing of more exotic clean energy technologies."

Below are some updated floor plans and a sketch of the proposed home design. The primary objective in these plans was to come up with a smaller Phase I dwelling that could pass occupancy permitting and allow us to move in and be livable. Phase II could be done later. One major change from the first draft is that I turned the "half pipe" into an gradual arch shape to help resist the back-fill pressure. Tim Hall recommends that we go with the parabolic shape (called "caternary vault") using 20-inch earth bags. He's going to be building the world's first structure of this sort this coming Feb. in Hawaii -- a 30-foot-long one --so he will have that experience to draw upon when he comes to help us build our home.

I'm guessing that most of our budget and time will be gobbled up in Phase I, so Phase II may have to wait a while.

These plans are drawn to scale (2 mm = 1 foot in the original). We'll probably make the utility room smaller and use an external building wired in to the home. The utility room will also need to fit our main cistern, water heater, radiant flooring control. The batteries can be located in the external building.


Cheri generally doesn't like the bee-hive earthbag look, so we went with a more traditional shape for our kitchen and living area. However, she did like the architecture shown on the cover of Earthbag Building. Both of us like the coloration and the framing of the windows.

If it weren't for this find today (thanks to Renee), the Phase II master bedroom would be shaped the same as the kitchen/living room area. We would like to do this kind of thing with all external windows, and maybe even the doors and windows that will run through the solarium.Now that I've pared down the plans, I'd like to ask my question again of Tim and Owen: Do you think Phase I is doable in the 180-day time-frame given per the 1031 roll-over constraints (I'm not yet sure when that begins/began; signing was on Oct. 30).Our tentative work force presently consists of:
- Sterling: FT, owner- Tim Hall: FT, foreman/instructor
- Torg: FT, SHV member
- Aaron: FT, SHV member- people that will trade labor for dental work from John- volunteers/interns that Torg can drum up- a few other SHV members/associates here and there.

As for the electrical considerations:
- I plan to go with DC for most major appliances, but we will want to have GFC circuits in the kitchen for things like Vitamix, Food Processor, etc.
- We'll want to have 2-3 AC outlets in the living room
- I would like to have at least one AC outlet in each room for things like radios, etc. that require it.
- I'm not sure what code requires when DC is being used predominantly
- all lighting can be DC

Here are the updated plans and sketch. I think it looks like a hot dog, so I'm afraid we're going to have the not-so-sexy name of "Hot Dog House".

(Click on image for enlarged view.)

Post 3: Vincent Powell's cartoon of our home's renewable energy layout

Today, Vincent Howell posted a diagram of the renewable energy components of our house design, as he understands them. It stirred up some dialogue which I've posted below:

On Nov. 7, 2009, Steven Dufresne wrote:

Hi Vincent,

Nice drawing! I like the hand-drawn look to it too. You've done a lot of homework.

By the way, you wouldn't have the generator output and the inverter output both going to the breaker panel. I've replaced two broken inverters because of people installing them that way. For some inverters, this feeding generator output to the inverter's output breaks the inverter and for others it just generates a fault. What people incorrectly do is have both outputs go to separate breakers in the panel so that when the generator is on, the inverter break would be turned off. But then one day they forget, and ... I don't know how it works in a grid-tied system where both the grid and the inverter go to the same panel. Inverters can take generator AC as input and pass some of it through to the breaker panel and use some of it to charge batteries. So the generator output would go to the inverter and only the inverter would feed the breaker panel (and no charge controller for the generator.) See: http://rimstar.org/renewnrg/sptypes.htm#OFFGRID The line with an arrowhead going from generator to inverter is how it's done.

There are also a few more disconnects. Basically, every component has disconnects around it so it can be isolated from the system for repairs. This is more for your information since drawing every disconnect in would make it very crowded.

Regarding the solar thermal, is this a climate with freezing outdoor temperatures? If so then water flowing outdoors in winter is an issue and the solar themal system would either be a closed-loop system with a distilled water/propylene glycol mix or a drainback system. Being in Ottawa, Ontario, Canada, I've only ever worked on closed-loop systems. For close-loop, see: http://rimstar.org/renewnrg/solarhotwater.htm

-Steve

http://rimstar.org http://wsminfo.org

- - - -

On Nov. 7, 2009, Sterling D. Allan wrote:

Hey Vincent,

That's pretty good!

Steve, thanks for your input as well.

Yes, we'll be in freezing temperatures through the Fall - Spring time here in central Utah. Rather than using the non-toxic ethylene glycol closed loop system (which is what my dad has in his home http://www.allanstime.com/SolarHome/), I plan to situate the thermal panels inside the solarium that will run the length of the home (the half-pipe section of the home). That way I can just run regular water through it. I also plan on heating a large cistern of water for thermal mass storage, then run the radiant flooring and hot water for the home from there. The possible gotcha there is if we are away somewhere during the winter and one of the solarium windows breaks, possibly introducing a freeze to the system. But our community will likely be keeping an eye out, and until they are established, we can have friends check in on our place while we're gone.

By the way, on the rocket stove, one of the designs I saw had a vertical feed as well for the incoming wood, so that gravity would take care of the hopper, taking away the need for manual feeding, which would be very annoying. But the thing is, you'd have to make sure the stove was going good before starting up the vertical feed, because you certainly would not want the fire/smoke to start going up the vertical feed portion.

I envision a dual feed system. On horizontal as normal, and the other coming in at 45-80 degrees, V-ing into the horizontal feed. You would start the rocket stove with the horizontal, then once it is going good, introduce the vertical feed. The vertical feed might need a damper on it to keep the smoke/flame from going up it during start-up.

I also plan on running the rocket stove exhaust pipe through some seating in the living area to heat up that thermal mass. So by the time the exhaust leaves the home, most all of the energy has been dumped into the home for heat or energy.

- - - -

On November 07, 2009 3:14 PM, Vincent Howell wrote:

Hi Sterling,

Thanks.

You wouldn't have to use ethylene glycol in the closed-loop system presented in my drawing, if you just follow simple procedures to ensure the water never gets below freezing. But placing the thermal panels inside a solarium is a good idea too, plus you wouldn't have to worry about adding extra stuff to your roof.

In case you ever chose a stirling engine set up to charge batteries during days of low insolation (overcast) and no wind, I would construct a small closet or room in the house right behind the rocket stove, so that part of the hot cylinder can be fitted inside the stove. This room/closet can also be the place to store the hot water heater and most of the piping. A stirling engine is relatively quiet but a 2-5 HP motor might make some mechanical noise. I would line the closet walls and door with quality sound dampening foam. This way you can enjoy the stove heat in your living room without hearing the engine on the other side of the wall.

I like the idea of channelling the stove flue around the house to obtain as much heat as possible. However, you have to clean the flue now and then because creosote builds up and can ignite a fire in your chimney. Can that be done if the flue isn't vertical?

- - - -

On November 07, 2009 4:10 PM, Vincent Howell wrote:

...The charger would need to accommodate the varying performance of the stirling engine--it wont always or ever run at 3600 RPMs to generate 60 Hz AC. In general the engine RPM and performance will depend on how hot the fire is in the stove. I think one could just rectify the generated AC to DC then use a wind turbine charge controller rated for about the same power or more. I'd say a 2.5 or 3 HP stirling engine would generate about 1,500 watts after generator losses. Therefore a simple wind turbine charge controller rated at around 2kW would work.

Post 2: Chat w/ Owen Geiger about earth bag design

Here's the first draft of my proposed floor plan. It's not to scale.





Below is an excerpt from recent correspondence with Owen Geiger, an expert in exotic renewable building designs such as earth bag, earth ship, straw bale, etc. His sites include http://earthbagbuilding.com/ ; http://www.greenhomebuilding.com/ ; http://www.dreamgreenhomes/. He was kind enough to join our Safe Haven Villages social network site to offer his assistance.

(Unfortunately, I don't yet know an easy way to import the email text into blogspot so that a bunch of extraneous line spaces are not added, etc.)




Dr. Owen Geiger, Ph.D. in Social and Economic Development, is the former Director of Builders Without Borders and Founder and Director of the Geiger Research Institute of Sustainable Building (http://www.grisb.org/). He is an author, engineer and licensed contractor specializing in strawbale construction, earthbag and other types of sustainable building. He co-authored the Builders Without Borders Straw-Bale Construction Guides and contributed to Building Without Borders: Sustainable Construction for the Global Village. Dr. Geiger has consulted on numerous international housing projects, worked closely with Habitat for Humanity for seven years and mentored housing officials with the United Nations Institute of Training and Research. He is also a correspondent for The Last Straw Journal and a Mother Earth News Green Homes Expert. Email: strawhousesATyahoo.com

From: Owen Geiger

To: Sterling D. Allan
Sent: Friday, November 06, 2009 12:25 AM
Subject: Re: building questions

Hi Sterling, My comments below in red. Owen --- On Thu, 11/5/09, Sterling D. Allan wrote: From: Sterling D. Allan Subject: Re: building questions To: "Owen Geiger" <strawhouses {at} yahoo.com> Date: Thursday, November 5, 2009, 10:57 PM Hi Owen, Thanks for taking the time to respond. Would it be okay if I posted our dialogue or excerpts in a blog? [linking to your site(s)] Sure, why not. [...] I had been told by Tim that the way the half pipe is constructed in the earth bag tradition (Cal-Earth) is to create a form, then do the compact/cement earth around the form to a thickness of around 6-8 inches. The forms are 8-10 feet long, and are moved down, then forward with each new segment, so the protrusions such as beams would be inserted between sections. This is called an earthbag vault. I am familiar with Cal-Earth's work, but unfortunately Nadir published very few details about his work. You'd have to attend his $2,000 workshops to learn details. [...] Do you know the people over at Cal-Earth? No I don't. Is there someone there I could talk to about the half-pipe and doughnut portion of things? They'll probably charge you a small fortune if they even answer your email. Perhaps the "hole" portion of the roof would be problematic when it comes to rain and freezing, so I would need to externally form a flat portion over the hole so that rain goes off that portion. Hmmm. It's not sounding very enticing to me. A 20' diameter room isn't big enough for living room, kitchen, and dining. I was thinking I could get larger by going with that shape. I'm open to alternatives, including doing hybrid methods -- e.g. rammed tire for one portion, earth bag for another, etc. You can buy metal dome-shaped frames and stack the bags around it. This has not been done before to my knowledge, but it should add enough support for a 30' diameter dome or so, especially if the bags are filled with lightweight material. Again, this is untested and just a guess, so please be careful. It looks like I need to get out some clay and start playing with different shapes to form my house in a model before building it for keeps. Modeling can be very helpful. Also, start small and add on later. I would start out with 1-3 small and medium sized domes to get the hang of things. This would provide basic shelter while the rest of the house was being built. This is where you need to be careful with building officials. Finish one section (bedroom, kitchen/living, bath) and get your certificate of occupancy. (Do not show them the entire plan that's on your website.) Then you can add on at a more leisurely pace. Continuously working on an unfinished house for years can create problems with building officials. As for location, we're pretty committed to locating here in Sanpete County, Utah; so we'll have to put up with whatever bureaucracy they will throw at us. There is at least one person there who has a solar home and would thus be more amenable to innovation. Then I recommend talking to them as soon as possible. Many areas don't allow alternative building methods. Sure, there's a loophole in the code that supposedly allows for it, but they can make life so difficult and expensive that's it's not practical. For instance, they can require any number of engineering tests to prove what you're proposing is safe. Sterling ----- Original Message ----- From: Owen Geiger To: Sterling D. Allan Sent: Thursday, November 05, 2009 3:54 AM Subject: metal roofing over half pipe Sterling, One option is to put curved metal roofing over the half pipe. You could glue/shoot (Ramset http://www.ramset.com/) wood sleepers on the half pipe every 24" and then screw metal roofing to them. You'd want at least several inches of foam between the sleepers. This could be sprayed on in order to seal leaks and fill everything uniformly. Metal roofing can be custom ordered to any curve you want. This would create a strong insulated roof with metal roofing for roof water collection. They make heavy duty metal roofing that will last 100 years. Also note, arched door and window openings in the half pipe are strongest and will allow for larger openings. Also, I have a huge collection of renewable energy links. Giant, as in every possible system available. But I would need to know what resources are available. For biogas, for example, you'd need a source of manure. Are you going to raise cows? Or maybe you could grow sunflower seeds, etc. and press the oil. There are many possibilities. There's a new community scale concentrated solar dish for around $75,000 that uses top of the line Sterling engines. Owen ----- Original Message ----- From: Owen Geiger To: Sterling D. Allan Sent: Thursday, November 05, 2009 2:41 AM Subject: Re: building questions Hello Sterling, You have some fascinating ideas and I'll gladly share what I know. First, it looks like you are using precast concrete half pipe. Is this correct? I've never seen this done before! So the main section of the house is a long tube? Are you sure half pipe is available in this size? How will you cut holes? How will you insert roof poles? You need to find some way to insulate the exterior surface. This would keep the thermal mass on the inside. Plus, it would be good to cover the inside with something to improve acoustics. Concrete looks, feels and sounds terrible. At the minimum I would use a heavy drywall texture. Earthbag domes at each end are fine. The largest safest diameter is around 20' interior diameter. The world's largest is 24' interior diameter and they ran into some problems and had to rebuild part of it. Anything over 20' will be dangerous and difficult. See Om Dome: www.earthbagbuilding.com/projects/omdome.htm Egress regulations and interpretations of code vary from region to region. Ask your local code officials what they require. Which reminds me to tell your group about the importance of selecting a building site with minimal building codes! I can't emphasize this enough. Areas with stringent codes will cause construction costs to inflate many thousands of dollars. Some rural areas only require permits for septic systems and give you total control over how to build. Imagine if every house cost $10,000 extra. That's a lot of money taken out of your community that could be put to better use. I'll put other responses below in red. Owen --- On Wed, 11/4/09, Sterling D. Allan <sterlingda@pureenergysystems.com> wrote: From: Sterling D. Allan <sterlingda@pureenergysystems.com> Subject: building questions To: strawhouses@yahoo.com Date: Wednesday, November 4, 2009, 9:01 PM Hi Owen, Here are a few questions to start out. I've got a rough sketch of my proposed home plan at http://www.peswiki.com/index.php/OS:Sterling_Allan I was planning to do the earth bag, beehive-like construction on the east and west sides of the home, with the half-pipe construction running between them. Questions: Is the general layout as I propose feasible? If not, what would need to be changed? Looks good for the most part. You're showing two domes on the left that overlap. Actually, they'll sit next to each other like on the right side. If I have the hall running through the solarium, instead of one along the north wall as well, will that satisfy code egress rules (if I have the window and door on the same wall?) I would put the hall through the solarium. (If you code allows.) The hall on the north is mostly wasted space. This would put a window and door facing south, which brings extra light into each room. I was thinking of embedding wood beams every 6-10 feet both for appearance and to form the solarium roof support. I have been told that the earth bag construction would not be strong enough to hold those up. Suggestions? I guess I could just tie the Solarium to the outside of the half pipe. Earthbags can hold it, but you'll need to add a concrete bond beam for the pipe to rest on. If needed, this study documents bearing capacity of earthbags: http://www.earthbagbuilding.com/pdf/Daigle_Bryce_C_200809_MScEng.pdf In the living room / kitchen area, I hope to do a pillar in the middle, arching out to the outside walls, making a doughnut shape, making for a larger room. Is that feasible? No pillars are needed unless you go over 20', which like I said gets difficult. Not sure what you mean by a doughnut shape. You mean a large circular skylight on top? That's no problem. How hard is it to do water capture from the roof of an earth bag or half pipe shape? I was planning to have three cisterns, one on the east, west, and middle of the home. You should be able to attach metal gutters to channel water into the cisterms, no problem. Just make sure the final roof coating isn't toxic. Where could I find some good info addressing the questions I'm posing above? YouTube videos, floor plans, principles explained, plans described? Our website at http://earthbagbuilding.com/ covers everything related to earthbags. I would also buy Doni and Kaki's Earthbag Building book. On the half pipe, you'll have to network with locals who work with it. I'm sure they have special tools for cutting, grinding, etc. You could possibly pay them by the hour to do all the cuts, as I assume they have industrial tools for this. Would you recommend that I go watch/participate in construction underway elsewhere before trying to tackle these things myself, or would having at least one experienced person come help me be enough? Tim Hall is willing to come help for like a month (for a reasonable fee). http://peswiki.com/index.php/Directory:Tim_Hall This is the guy who's building in Hawaii. So yes, someone like this will be a big help. It all boils down to basics, but it sure helps to get things started in the right direction, reduce errors, speed things up, etc. Everyone who's planning on building with earthbags should join in at least 1-2 days to learn as much as they can.

Post 1: Progress so far toward establishing our home in a new intentional community

Okay, folks! It's about time I start a blog to chronicle the saga of building a sustainable home.

This blog will supplement the overview page at http://www.peswiki.com/index.php/OS:Sterling_Allan%27s_Sustainable_Home which is part of the http://safehavenvillages.org/ intentional community project, with mission statement:

Safe Haven Villages are intentional communities based on principles of sustainability, educational outreach, healthy living, natural healing, individual responsibility, cooperation, and renewable energy. We are dedicated to an earth-friendly, family-friendly environment through commitment, honor and integrity (CHI).

I should have started this blog earlier, considering all that we've been through already, to get to this point; but at least I'm getting it going now.


The main context here is that we are rolling over the value of our Eagle Mountain (UT, USA) home in a 1031 exchange to 1) purchase land for the community, 2) purchase materials for our home. We'll rely on the community, primarily, to help with labor in building the home, seeing as we used a large portion of the value of the home to secure land for the community, including for our home.

This will be a highly challenging time for me as I will be required to ...

1. keep earning a living, keeping my Free Energy News and Directory service running;


2. come up with a design for our home;


3. find land on which to build the community;


4. get a building permit;


5. help with the Planned Unit Development (PUD) for the community property;


6. get roads, power (e.g. temp), and water (e.g. temp) to the property;


7. build the home;


8. find the best renewable energy sources and match them to appropriate appliances

It entails learning new building methods, including thermal mass integration, radiant flooring, rainwater capture, cistern plumbing, gray water handling, renewable energy power and integration. I would like for the home to be completely self-sustaining, including power, water, food, and sewage.

Some of the major developments to date have included:

• Getting our Eagle Mountain home ready to sell


• Establishing the Safe Haven Villages founding documents: mission statement, vision statement, membership types and expectations


• Getting an offer after just 23 days on the market


• Finding a solar guest house to rent while we build


• Moving to the guest house on Oct. 23, 2009


• Closing on Oct. 28; funding on Nov. 3 (we now have 45 days to identify three properties to choose from; then 180 days to build or otherwise roll over the value of the Eagle Mountain home)


• Locating (thanks to Susan) a number of interesting properties (land) to choose from, in Sanpete County, UT, USA; making several offers.

And so, we pick up with the saga. As of today, we just looked yesterday at a couple more properties, so we need to weigh and decide where next to put an offer or counteroffer.

For the Safe Haven Villages social network members, here's a report I just posted on the two properties we looked at yesterday.
http://utahsafehaven.ning.com/profiles/blogs/property-report-40-acres-w

Here's a video I shot: http://www.youtube.com/watch?v=AHcPaJyrw_c

This blog will contain the more public information, while the social network site is more private.

We invite and look forward to your input if you have good ideas for us, as we are on a tight learning curve here, and we hope to integrate some of the best products/approaches presently available into an appealing design.

We want our home to be affordable and a showcase of sustainable building and living.