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[ripsnort]

dry stack block. 
just stack standard concrete blocks up without any mortar. 
stack around where you want windows and doors - bullnose if you want. 
then parge both sides with block bond which is a mortar/fiber mix.
then put rerod in the vertical block holes and pump in concrete.
build box beam around the top of wall to support roof.
put on whatever roof you want.
then attach styrofoam on the outside - comes in 4'x16' sheets.
order foam straight from factory sliced any width you want.
use the performguard formulation which is insect proof.
attach to wall using the anchor bolts inserted thru drilled holes in blocks.
then parge over the styrofoam with the same blockbond but with liquid plastizer added.
low skill levels til you get to the roof.
monolithic - incredible thermal mass, almost no thermal bridging, rot, insect and pest proof.
can be made very intrusion resistant.
can build it on a slab or full foundation.

[J13]

hello ripsnort
i do like the idea of using dry-stacked block, however, i wonder how much it would cost for the concrete/block/rebar combo especialy when filling the cores of the block. 5000 psi concrete in my area costs about $95 per cubic yard, and for the size home i would like i was seeing a HUGE amount of concrete (my math could've been off quite a bit) the bill for the concrete alone was into the mid to high 6 figures - if im going to spend that kind of $$ on a project like this, i'll build it out of full hard armor plate, that is if i had the money to begin with....

i've seen something called grancrete, seems very promising....

J

[Aviator]

J13,

I just calculated the concrete required just for the walls--just an estimate--for the 2212 sq foot ICF house design I posted.  It comes to 60 yards with nine inch thick concrete and a total wall thickness around 15 inches.  That comes to $6000 at $100 per yard.  I think that's very reasonable.  You could easily double or triple that depending the foundation or basement, but you get what you pay for.

[Ian]

I think drystacking would work very well for DIY type projects, as those tend to be smaller than the 4000+ sqft mansions a lot of people seem to be fixated on today. If you build something in the 500-2000 sq ft range, the cost of concrete of easier to deal with. Also, drystacking allows you to mix and pour all the concrete yourself, and just build as you have the time and money. A course of block here, two courses there, and before long you have your walls up.

I would plan to go overboard on waterproofing for a dry-stacked building, though. I don't know just how effective the surface mortar is as a waterproofing agent, but I do know that before it's applied a drystacked wall will leak like a sieve. In fact, you can see cracks of  light through many/most of the joints between blocks. If I were doing such a building, I'd definitely plan to use surface mortar, and then another sealant - possibly something like roofing tar. And (if it was bermed) a french drain at the foundation level and another just below the surface (to catch and direct runoff).

Edit: Just as an example, a 10x20x8 dry stacked building (without accounting for a door or windows) would require roughly 500 8x8x16 blocks, 3.5 - 4.5 yards of concrete in the foundation (assuming a 4" slab with 12"x12" footings all around), and another 4.5 yards or so to fill the cores of all the blocks. That comes to a total of about 300-325, 80lb bags of concrete. At $3.40 each, that's a bit over $1100 for concrete. Assuming the blocks are $1.25 each, you're looking at about $1800 in block and concrete.

In addition to that, you'd have to factor in cost for rebar in the footings and walls, insulation, surface mortar, water sealant, roof materials, and any interior finishing you have in mind.

[ripsnort]

J13, you don't say how big "the size home i would like" would be, but two things:
    - unless you are planning something really enormous recheck your math.  I can't imagine how you are coming out in the "mid to high 6 figures".
    - keep in mind that structurally you only need to rebar and mortar a core every few feet.  Yes, mortaring every core does add thermal mass and "other qualities".
Also remember you have to hire a concrete pump truck.  You want a small one with a 2 inch hose.  There are several coatings like grancrete but they tend to get $$$ and the spray on ones require specialized equipment - more $$$.   
Ian, Yes dry stack is good for DIYers, but I wouldn't think of mixing all the concrete and lifting it up to pour it down into the blocks.  Unless you are dong a really small building just get it delivered and pumped in.  The parging of the blocks and insulation will provide all the concrete mixing you care to do.  Also, you can only put full length rerod in if you pour the whole full height core at once.
There is no water problem with this construction - you are parging both sides of the block, then putting 4'x16' sheets of styrofoam on it, then parging over that with a plasticized parge. 

[Ian]

ripsnort, one of the reasons I like the drystack method is that it can be done without any hired help, if need be. Which makes it a feasible method for a gulcher planning to avoid local building codes and inspections. Hiring help (or having deliveries) always brings a risk of being reported to the local government. Yeah, it'd be a hell of a lot of work, but it would be doable - especially if it was done bit by bit over several months or more.

[coloradohermit]

Just a note about that polystyrene foam. We put it on our poured concrete N and W walls. Where it was visible about the backfilling, the ducks ate it all off. So covering it with something would be a good idea.

[teotwawki]

Go Kaczynski!!!! 

ripsnort, one of the reasons I like the drystack method is that it can be done without any hired help, if need be. Which makes it a feasible method for a gulcher planning to avoid local building codes and inspections. Hiring help (or having deliveries) always brings a risk of being reported to the local government. Yeah, it'd be a hell of a lot of work, but it would be doable - especially if it was done bit by bit over several months or more.

[J13]

hello all

the size of home I'm trying to build is approx. 2000 ft^2 - this may be able to be reduced somewhat, I've tried putting together several rectilinear designs using a wall thickness of 8 inches and 4 inch thick floors i got a total of 1667 yd^3 needed for cast in place concrete, the garage took the same amount for a total of 3334yd^3 for a total price of 316,730 for the concrete alone. This does not include installation of this concrete into a useful form, nor does it include any rebar, delivery, finishing (of the structure itself, I'm competent enough to do the inside work, but not the physical load bearing design of the earth covered home), design, well, septic ect...
ballpark guestimate for a structural engineer to look at, approve, modify and sign off on prints that are acceptable to the zoning board (no permits for the structure= court order to demolish it, if you don't they will while you are in jail - its BS i know, but thats ny..and another thread...)

the attached garage which would be of the same construction and measure at least 30 by 40 by at least 14' high this too is planned to be earth bermed

berming is for camo, insulation efficiency and protection and includes the roof

thanks
J

[Ted Nielsen]

OK lets say you have a 50X40X10 home. The floor will be 50'X40'X4" which works out to 667 cubic feet or about 25 cubic yards. the walls are 180'X10'X8" which works out to 900 cubic feet or about 33 cubic yards. This doesn't include openings for windows or the footings for the foundation.

[ripsnort]

Ian, "avoid local building codes and inspections"?  None here, what are they?  Avoid the attention of the local government?  Not many places in the U.S. that remote and most towns look at the new aerial photo maps when they come out every ten years.  I know many buidings that have been found that way.

coloradohermit, I said in both my posts that the foam is covered or parged with "block bond which is a mortar/fiber mix".  You should have at least put some Grace rain water shield on yours.

J13, check Ted's figures on the 40x50x10' house, then recheck your calculations.  You are probably making a basic conversion mistake.  Think of this: a solid block of concrete 40x50x10' would contain less than 750 cubic yards of concrete.  Yes? someone recheck that for me.

[Aviator]

A mixer truck carries TEN yards of concrete--what house would take 300 truckloads of concrete?  Measure the surface area of the walls--the perimeter of the building times the average height in feet, then multiply by the average thickness of the material in the wall, I would think 0.4 feet would be close for filling cement block.  This will give you the volume in cubic feet for the walls.  Divide this number by 27, this will give cubic yards.

Another thing about ICF, the ties between the foam pieces--those are supports for horizontal re bar.  A properly done ICF house has both vertical and horizontal re bar.  This is why they are so strong and easily meet building codes.  Also, I would VERY strongly advise you to have building permits and make sure everything meets or exceeds code.  You may want to sell your house some day, and no matter how you build it, it will be a big investment.  Another thing, you want the place to be one that you want to live in.  There is no reason why a very strong, secure house can't be an attractive, desirable place to live.

[Rarick]

okay just a quick calculation for the walls: 

Traditional Box with 6" thick walls. would need 22 Yds³.  A half foot for the basement floor and cieling would be another 74Yds³ Total of 96Yds³Â   That is just concrete, no roof, cinderblock, or second floor framing.

A dome with the same internal volume would be 50' in diameter, 18' high. Use a total of 56Yds³ of cement for the dome and 72yds³ for the basement and its roof. For a total of 128Yds³Â  That includes your second floor and roof. 

I did not count windows, doors, oe ant thing else into the calculations, just concrete.  The dome is complte as far as the outside and weatherproofing goes.  The Box still needs a floor framed in and a roof.

Calculators for the domes:  www.monolithic.com/plan_design/calcs/   I used the "spherical dome" column.

[JOROWA]

My monolithic house has 5000 square feet of floorspace including the integral garage, and we used 165 yards of concrete for the shell, floor, and footers.

The biggest problem with all of these alternate construction methods is that banks hate them, as there are no comparables for basing valuations on.  Therefore, they don't want to lend you money for them.  They are worried about what they could get for the house if they had to foreclose, or even worse, have to complete an unfinished construction. 

[Rarick]

sources to consider when evaluating balistics for the walls:

clairewolfe.com/wolfesblog/00001296.html
globalsecurity.org/military/library/policy/army/fm/3-06-11/ch7.htm

Also check out SurvivalBlog for other tricks and tips.