Peaceful Valley*
Permies likes green building and the farmer likes Dry stacked concrete blocks permies
  Search | Permaculture Wiki | Recent Topics | Flagged Topics | Hot Topics | Zero Replies | World Domination!
Register / Login
permies » forums » building » green building
Bookmark "Dry stacked concrete blocks" Watch "Dry stacked concrete blocks" New topic
Author

Dry stacked concrete blocks

Roy Hinkley


Joined: Jan 22, 2011
Posts: 28
Location: S. Ontario Canada
Hi folks, new to these parts.

I've been looking in to these kinds of alternative methods for a while and thought I would share the best thing I found so far.
I found this guy's site a while back and it's too cool.

I think I'll be using this method for a partial earth bermed house unless I find something better.
The surface bonding technique is 3 times stronger than traditional concrete block construction, bug and rot proof, relatively inexpensive, huge thermal mass, low skill. Plumb the slab floors for (solar?)hot water heat, insulate the exterior(hay bale?) for colder climates......
Strong enough for green roof..... 
Over 100 pages of pics
http://www.texasmusicforge.com/gimmeshelter.html
Len Ovens


Joined: Aug 26, 2010
Posts: 1270
Location: Vancouver Island
    
  15
I hadn't seen that one... heres two more:

the first one is one of the permies posters:
http://flashweb.com/home/cottage

and the second is one I saw a few years ago:
http://www.thenaturalhome.com/passivesolar.html

All three are very different. The big thing I can see is ease of getting a permit. The other is speed of build even as a DIY. A container might be quicker, but I don't think cheaper.

I like the small cottage as it seems very well laid out.

All of them are built for their location and different heating or (in Texas) cooling needs...
Doug Gillespie


Joined: May 04, 2010
Posts: 77
Dry stacking is very cool, especially if done with blocks specifically designed for it.  There are a number of different designs, some of which are so Lego like it makes the whole process look like just too much fun.    They tend to be a bit pricey compared to standard cinder blocks though. 

Anyway, it's certainly a technique that's approachable for the inexperienced owner builder.  We looked into it, along with slipforming with stone and concrete, quite seriously.  The problem we have with it is the absolutely enormous emobodied energy of the concrete block and cement.  We've been shying away from cement and moving towards earthen construction in our plans.   

Doug
                                    


Joined: Nov 08, 2010
Posts: 147
Location: Anoka Sand Plain, MN Zone 4/5, Sunset Zone 43
I wonder if it'd be cheaper to make or buy your own brick maker rather than buying the bricks.  Anyone else familiar w/open farm tech?
Ed Waters


Joined: Dec 01, 2010
Posts: 101
Perfesser, we looked at straw bales, slip form, poured in place, dry stack, and bought the Natural Home plans and video.  In the end we settle on ICF's.  The house we are building is bermed.  We bought are ICF's from ARXX.  They were around 22 dollars a piece for 48" x 16".  Concrete was 92 dollars per yard for 3000 PSI, and rebar for the whole building was around 500 dollars.  Codes are going to become a huge issue going forward.  The spike in building permits witnessed in 12/10 was due to new Federal laws mandating specific r values in building structures.  Traditional construction like logs is going to have a problem going forward.  Our plans were done for pip, and our inspector said if we had left it without insulation shown he would have had to reject it.  If you have any questions I would be happy to try and answer them.  Pictures here: http://luckydogfarm.wordpress.com/
Ed
Roy Hinkley


Joined: Jan 22, 2011
Posts: 28
Location: S. Ontario Canada
Thanks for the replies and thanks for taking all the pics Ed.
We bought our land a couple of years ago and have been investigating since then.  This year it will be where the wallet meets the architect.
Then I'll know just what we can do.
Abe Connally


Joined: Feb 20, 2010
Posts: 1381
Location: Chihuahua Desert
The surface bonding technique is 3 times stronger than traditional concrete block construction, bug and rot proof, relatively inexpensive, huge thermal mass, low skill.


I've built with this technique, and I was NOT impressed.

A few things:

Don't do it with regular concrete (cinder) blocks.  Uneven edges and stacking creates issues.  You can't get any levels plumb, even with shims.  Not using a standard block increases cost.

These walls are not as strong as they say.  2 weeks after completing a 2 ft tall wall, we backfilled behind the wall, and several bricks shifted and moved out.  It was very disappointing.  We remade a section with mortar, backfilled it, and didn't have any issues.

It is NOT fast, not low-skilled.  I found it faster to set blocks in mortar than mess with leveling and adjusting to keep things in line. A lot of time is wasted by adjusting the blocks, whereas mortar absorbs imperfections.  Having really nice blocks ($$$) might help with the speed.

I thing earthbags beat this is nearly every way.


Living off grid - guides for the off grid lifestyle in the modern age
Homesteading - latest updates and projects from our off grid homestead
Len Ovens


Joined: Aug 26, 2010
Posts: 1270
Location: Vancouver Island
    
  15
Ed wrote:
Perfesser, we looked at straw bales, slip form, poured in place, dry stack, and bought the Natural Home plans and video.  In the end we settle on ICF's.


Looks real easy to do. Lighter to lift than dry stack and bigger blocks for speed. I looked at "BuildBlock" ICFs and assume yours are similar. 2.5 in. of foam on either side. This wrecks it for me. I would prefer 5 in. on the outside and none on the inside. The inside would have to be a drywall substitute or something mud would stick to.... or something removable. For me the whole reason of  a concrete wall is heat storage. I want that next to the living space, not insulated from it. Right now dry stack block is my top of list with insulation on the outside.  My Yf grew up with cinder block housing and the blocks just painted, that was not dry stack though, dry stack has to have stucco both sides. So my outside would be stucco/insulation/stucco or siding.


Our plans were done for pip, and our inspector said if we had left it without insulation shown he would have had to reject it.


Ya, has to have insulation either inside or out (out is better) concrete doesn't have much r value.


  If you have any questions I would be happy to try and answer them.  Pictures here: http://luckydogfarm.wordpress.com/
Ed


I like the style, with the lookout. looked at the pictures, looks straight forward to build. I think the mass of the concrete will still help to even out the temp both summer and winter. The plus will be that a room will heat up quicker if it has been cold.
Ed Waters


Joined: Dec 01, 2010
Posts: 101
What Vela said.  I'm scared enought building anything myself but the thought of a permed house with drystack was too much to worry about.  To do it right you have to fill every 4th hole in the blocks.  That's alot of concrete to mix by hand, and if you have a truck bring it in you will need special equipment which makes the concrete more expensive.
Len: We used a company called ARXX Blocks out of Canada (we are in NY).  If you look at the pictures on our blog we have begun to stucco some sections of the exterior, and will do alot of areas inside as well.  Our house is 24 feet deep and the sun even on 12/21 won't make it to the back wall.  The blocks have a webbing that goes front to back and you can see it as black exposed strips.  You can screw just about anything into those strips using deck screws.  The blocks even without the berming are R-51.  We have the drawings on a pdf. and I can send them to you if you want them, keeping in mind that they are for PIP, which made for some difficulties when using ICF's but nothing that can't be over come.

Ed
Len Ovens


Joined: Aug 26, 2010
Posts: 1270
Location: Vancouver Island
    
  15
Ed wrote:
What Vela said.  I'm scared enought building anything myself but the thought of a permed house with drystack was too much to worry about.  To do it right you have to fill every 4th hole in the blocks.  That's alot of concrete to mix by hand, and if you have a truck bring it in you will need special equipment which makes the concrete more expensive.

I would be filling every hole, if not concrete, dirt or sand. I want mass.


Len: We used a company called ARXX Blocks out of Canada (we are in NY). 

Spent a lot of time looking for APXX... oops.


If you look at the pictures on our blog we have begun to stucco some sections of the exterior, and will do alot of areas inside as well.  Our house is 24 feet deep and the sun even on 12/21 won't make it to the back wall. 


mass collects heat in other ways besides direct solar radiation, it collects it from the air and stoves and our body too. I'm not saying I know the best way (I am sure I don't), but I want to try high mass. I should probably start with a cottage similar size to the one at Sugar Mountain. High insulation can work too. It's just not my current thing   (I have a few years before I start... so that may change)
Kay Bee


Joined: Oct 10, 2009
Posts: 471
Location: Jackson County, OR (Zone 7)
velacreations wrote:
I've built with this technique, and I was NOT impressed.

A few things:

Don't do it with regular concrete (cinder) blocks.  Uneven edges and stacking creates issues.  You can't get any levels plumb, even with shims.  Not using a standard block increases cost.

These walls are not as strong as they say.  2 weeks after completing a 2 ft tall wall, we backfilled behind the wall, and several bricks shifted and moved out.  It was very disappointing.  We remade a section with mortar, backfilled it, and didn't have any issues.

It is NOT fast, not low-skilled.  I found it faster to set blocks in mortar than mess with leveling and adjusting to keep things in line. A lot of time is wasted by adjusting the blocks, whereas mortar absorbs imperfections.  Having really nice blocks ($$$) might help with the speed.

I thing earthbags beat this is nearly every way.

I'm looking at building a house this year and dry stack block is at the top of my list.

Vela - could you perhaps expand a bit more on your troubles?  Particularly the stucco - in order to provide strength, I understand that you need to incorporate engineering fibers in to the stucco before it is applied.  Is this a similar system that you used?

I don't think berming will be absolutely necessary in our area due to a pretty mild climate, but I'd like to have the option to berm (and strength) if it turns out to be necessary once we see the thermal performance of the house.

We should be meeting with the engineer/architect in a couple weeks!


"Limitation is the mother of good management", Michael Evanari

Location: Southwestern Oregon (Jackson County), Zone 7
Ed Waters


Joined: Dec 01, 2010
Posts: 101
SEF: Vera will answer, but we also played around with it when we were trying to decide what to do.  You can get mortar mix with the fiber already mixed in.  It's been a while but that type of mortar is very expensive.  We our doing alot of stucco now, and it is alot easier, downside thought to do stucco right over ICF's you need 3 coats.  It was a little misleading for us.  Drystack looks cheap, but you have the special mortar, you still have to put all sorts of rebar in there, and more if you are going to consider berming at some point in the future(your arch/eng will make sure of that if their names are on the plans), along with the concrete in the holes.  My 2 cents
Abe Connally


Joined: Feb 20, 2010
Posts: 1381
Location: Chihuahua Desert
yes, we had the Surface Bond Stucco with fibers in it. It isn't cheap!

The system is not as strong or fast as I had read on the net.  For speed, the first thing were the blocks, we were using regular cinder blocks (cost$$), but they are so uneven, it creates a lot of leveling problems.  So, you have to add shims, and I think that might be the issue.  The shims don't help hold the lateral forces.

Also, we filled all of our cores for added strength and thermal mass, but it didn't help.  We had individual blocks push out of the wall.

I have built with many systems:
adobe, ferro-cement, cob, straw bale, papercrete, metal, ICF, rammed earth, CEB, brick, concrete blocks, surface bond, acrylic concrete, wood framing, and earthbags.

I love CEB's for walls, and Ferro-cement for roofs, but for cheap, bermed or buried housing, nothing beats earthbags on cost, speed, and overall simplicity.  Plus, they usually come out to 18" of very dense thermal mass.

Berming is really good for helping with the temperatures in the house.






                    


Joined: Oct 23, 2011
Posts: 0
On [url=http://countryplans.com/smf/index.php]Country Plans Forum we have had a few members build with dry stack blocks over the past few years. I don't recall anyone being unhappy with the end result. There is work involved for certain, with the application of the surface bonding cement being harder than it looks for some folks. I've tried mortaring blocks and that is not as easy as some folks make that look either.

Links to projects and comments
http://countryplans.com/smf/index.php?topic=5690.0
http://countryplans.com/smf/index.php?topic=4504.msg55022#msg55022
http://countryplans.com/smf/index.php?topic=2285.msg21849#msg21849

One member has a blog of his own outlining his experience. The following link is to it, but you will have to search for the beginning.  http://n74tg.blogspot.com/2006/12/block-walls-base-course.html


Roy Hinkley


Joined: Jan 22, 2011
Posts: 28
Location: S. Ontario Canada
What a wealth of info you guys have been. I can't thank you enough for sharing your experience. You given me much to reconsider before I have to visit the architect this year.

@velacreations
You mean to tell me you filled every core with concrete (rebar?) and after a month of curing it still pushed blocks out?
The whole reason I liked dry stacked was you could fill a core at a time(DIY) and not worry about cold joints.
I had planned to fill every other core with concrete and rebar  and the rest with sand.

I suppose ICF's are an option but I agree with Len on the thermal mass thing. I suppose you could pull the foam off the inside and glue on the outside, especially if you drape a sheet of plastic before you pour. That would give you 5" or more on the exterior.
I have seen what happens to foam in a fire. It won't support combustion but when anything around it burns it releases such toxic smoke I'm now a firm believer it has no place inside a dwelling.


Abe Connally


Joined: Feb 20, 2010
Posts: 1381
Location: Chihuahua Desert
You mean to tell me you filled every core with concrete (rebar?) and after a month of curing it still pushed blocks out?

We didn't have rebar in every core.  But yes, it pushed blocks out (not a lot, but like 5 out of a 2 ft tall wall, 30 feet long.

The whole reason I liked dry stacked was you could fill a core at a time(DIY) and not worry about cold joints.
I had planned to fill every other core with concrete and rebar  and the rest with sand.
I think the cold joint may be the issue.  If there isn't a solid beam of concrete, filling the core doesn't really help, there is a clean break right there.

Roy Hinkley


Joined: Jan 22, 2011
Posts: 28
Location: S. Ontario Canada
Sorry, I'll clarify.
Filling a single core, even 10 ft high should be no problem at all with a power mixer within half an hour.

I was thinking of some kind of hole or socket in the footing that you could drop a length of rebar into after the wall was built (so you wouldn't have to lift each block over) before pouring to handle the shear loads and then tie them all into the bond beam.
Rebar is cheap and you only get one chance to get it right. Prep is everything.

I read a few of the things in the links to Country Plans. One guy had trouble leveling the blocks and used a 3/8 mortar joint. You seriously compromise the strength of surface bonding. The fibres have to be able to span from one block to the next to do their job.



                    


Joined: Oct 23, 2011
Posts: 0
If the concrete footing is poured with short lengths of rebar embedded (with bent ends in the concrete) the lower course can be fitted over the protruding rebar. Once the wall is completed, then lengths of rebar, with a short L at the lower end, can be placed in the core and concrete added and vibrated down. No need to lift and lower over the longer embedded rods.
Kay Bee


Joined: Oct 10, 2009
Posts: 471
Location: Jackson County, OR (Zone 7)
Velacreations - thanks for the extra info.  Do you recall the dimensions of the individual blocks that you used?  I imagine they are standard size, but if I recall, you are in Mexico, so I was wondering if there are some differences.

I've heard a number of folks say that the application of the stucco (sparging?) is much slower than expected, so that doesn't surprise me, but laying the block sounds like it goes quick for most people.

Some of the threads at country plans (thanks MtnDon!) are great to follow the whole construction process. 
Abe Connally


Joined: Feb 20, 2010
Posts: 1381
Location: Chihuahua Desert
I seem to remember the blocks being 15.5 inches long, about 6 inches wide, and approx 8 inches tall.  I might be off by a 1/2" or so.

There was a variance of about 1/4" on the height of the blocks, thus causing a lot of problems.  Unfortunately, nice bricks without much variance are quite a bit more expensive, thus warranting a different, more efficient, less expensive method.

Most of the folks doing Surface Bonding haven't done much mortar+brick work, so they are surprised at the speed of stacking blocks. BUT, once folks learn the basics of laying blocks in mortar, they are surprised at the speed of how fast mortar goes.

I've done both, and I don't find either method much faster than the other.
Len Ovens


Joined: Aug 26, 2010
Posts: 1270
Location: Vancouver Island
    
  15
I did some reading on the ICFs. Pulling the foam off the inside is not so far off even in a standard install. You have foam on the outside and inside, but from the ARXX site, it seems the only reason there is foam on the inside is to allow inserting wiring and plumbing flush with the wall. So for any exterior wall you have a hole the size of an outlet every ten feet (yes our building code wants outlets such that an appliance placed anywhere in the room only needs 6ft/3m cord), plus a groove to run the wire all around the house in the inside R25 foam dropping your R value in half for all these holes... add wiring for baseboards if you are using those (cheaper here than gas).... lights and switches.... kinda like adding another window.... but without getting any light. They even suggest ducting for heating could be cut into the inside foam. If you are off grid and using a mass heater for warmth, you could do better. I wouldn't want any of my plumbing to be in the outside wall if I could avoid it anyway. I think if you are off grid and have no AC power anyway the building codes relax on the AC outlets. Calling something a cottage instead of a house helps too.

You can do curves... so long as they are a portion of a vertical cylinder. They show a lot of bracing... theirs looks specialized and expensive.... but I am sure I could do it cheaper with 2x4s. Sometimes stick built looks good   I am  (for now) back to the dry stack I think.
                    


Joined: Oct 23, 2011
Posts: 0
Re: the AC wiring and off grid. Where our cabin in the mountains is located, even though we are not connected to the grid the county building department insisted on the cabin being wired following the same requirements as any new residence in the county. Cabin, house or palace, to them they're all the same as far as meeting what the code books call for.

That may vary place to place. When it comes to codes it is always best to ask at the local level. That goes for all construction aspects. Of course there still are places with very limited or non existent code requirements.
Ed Waters


Joined: Dec 01, 2010
Posts: 101
Len: the distributors of the ICF's will in most cases let you use the bracing  for free for a certain amount of time.  Ours lay around for a couple of weeks after we used it.  Saw a great solution for  removing the foam for electric.  They had made a jig for a small electric chainsaw.  Worked really well.  Would stay away from any kinds of curves or anything special, that's where the whole process gets complicated.  I guess we should consider ourselves lucky in that we have alot of Amish living nearby so the inspectors have seen it all by now.  Also if you are the contractor there is a whole lot more leeway than if its something a contractor is building for you.  Lots of problems if you ever want to sell, but we are here for the duration.
solomon martin


Joined: Jan 17, 2011
Posts: 102
    
    1
christhamrin wrote:
I wonder if it'd be cheaper to make or buy your own brick maker rather than buying the bricks.  Anyone else familiar w/open farm tech?


I doubt it, making bricks is a pretty involved process, plus there are many outfits that specialize in salvaging bricks.  It would definitely be cheaper, quicker and faster to use recycled brick.
                            


Joined: Oct 13, 2010
Posts: 11
Rob Roy used surface-bonded dry stacked concrete blocks in his 70's earth-bermed home.  The home and its construction is documented in his "Underground Houses: How to Build a Low-Cost Home" book.  If I remember correctly, he mentioned sorting the blocks by size and using like-sized ones together to reduce problems.  In his book, "Earth-Sheltered Houses", written 25 years later, he lists the mistakes he made in his first go around, but I don't remember reading of any problems caused by the concrete blocks.  I just checked on the section where he talks about surface-bonded concrete blocks and he says he supports this method of construction.

I really like the dry stack approach.  The walls go up quickly and easily.  I am planning on a building a 200 sq ft earth-bermed, weekend shack using this technique this summer.
Walter Jeffries


Joined: Nov 21, 2010
Posts: 907
    
  18
Dry stacked is a great technique. An outer parge coat and core filling both strengthen it. We did this for most of our walls in our tiny cottage in addition to doing a little bit of poured with forms to experiment.

We started with the base of a steel reinforced floating slab keyed to the ledge of the mountain. As we went upward we filled the blocks with concrete and inserted rebar vertically.

At the half hight we did a bond beam with rebar horizontally. Then we continued up and repeated the bond beam at the top. This was easy to do and is very strong.

We parged the surface with a fiber reinforced sand cement mix. This last part is partially done.

For the roof we did a ferro-cement barrel vault.

This link leads to articles about our Tiny Cottage:

http://flashweb.com/blog/tag/tiny-cottage

The earlier articles in November and December are the most relevant to dry stacking:

http://SugarMtnFarm.com/blog/2006/11
http://SugarMtnFarm.com/blog/2006/12

Our next project is building a butcher shop. For this we're using form work but I still liked doing the blocks. The forms are stronger but cost a lot to build. It is worth it though since we have multiple projects.

Cheers

-Walter
Sugar Mountain Farm
Pastured Pigs, Sheep & Kids
in the mountains of Vermont
Read about our on-farm butcher shop project:
http://SugarMtnFarm.com/butchershop
http://SugarMtnFarm.com/csa
                              


Joined: Mar 12, 2011
Posts: 1
I didn't see anybody mention drystacked.com ... The guy who wrote the book and writes the site is very helpful and nice. It is a worth while read. He has plenty of technical info in there. When I built my house I was going to partially earth berm it, too. It didn't work out that way, but I did dry stack my thermal mass wall. It is about 7ft high and 35ish ft long. I didn't use surface bonding cement on it, though. It was cheaper to fill all of the cores with cement than to fill bond beams and use the surface bonding cement. To smooth it out I simply used gypsum drywall goop. It was quite a bit of sanding. I turned out quite well and absorbs and holds heat quite well. In fact the sun is shining, so the heat is on!! 

I did not have as much problem with getting the blocks leveled up as the others here. But keep in mind that I topped the wall did the ends with wood framing.
Jamie Jackson


Joined: Dec 04, 2010
Posts: 187
Location: Zone 5b - 6a, Missouri Ozarks
We read Rob Roy's "underground home" book, the USDA guide for dry stacked building, bought the book and videos from drystack.com.  None of these prepared us for how slow this process is because of the crappy blocks.  We have two small houses to build, both were designed for dry stack.  We are in the process of building the first one and are now considering another method for the second.

We cleaned the blocks, measured each side (they are almost always two different sizes on one block), stacked by the biggest size and we've done everything the experts have said.  It's still slow and painful.  Occasionally we'll get in a grove and lay 4 or 5 blocks without too much pain.  Maybe it's just the blocks we have, but one side will be 7 -9/16" high, then the other side is 7- 5/8" high, sometimes one side will be 7-1/2"! Then there are those blocks that are in between those numbers. 

This is definitely not quick or easy like the books and videos said and sorting by size doesn't seem to have helped any.  We've had to lower our expectations on what we consider level and plumb with these blocks. 

After reading this thread, sandbags sure sound nice.  I think we've spent most of our time turning blocks (sometimes they are so crooked that will make them suddenly level) or shimming.  Someone told us to use liquid nails as a sort of mortar, but that just squishes out and doesn't work either. 


Help support our homestead by checking out the "Health and Garden/ The Essential Herbal Magazine" on our blog: www.MissouriHerbs.com
Abe Connally


Joined: Feb 20, 2010
Posts: 1381
Location: Chihuahua Desert
that's pretty much the experience we had with them!  I won't ever do that again....

earthbags or CEBs, please!
Walter Jeffries


Joined: Nov 21, 2010
Posts: 907
    
  18
Interesting. The blocks we got were very precise. The sides were smooth, the edges sharp and the measurements all exactly equal. Stacking went pretty fast. We core filled with rebar and concrete after doing half the wall and then again at the top - that took more time than the stacking since we mixed all the concrete in a small mortar mixer. This emphasizes that it is critical to find out the quality of the blocks. Unfortunately one often doesn't have very many suppliers to choose from within a reasonable distance. Ours were delivered on two trucks from about an hour away. We got lucky.
solomon martin


Joined: Jan 17, 2011
Posts: 102
    
    1
From a mason's perspective:
CMU's are designed to be used with mortar.  Having said that, for convenience, to save time or material costs, or to just be a good earth citizen and use less cement, the  dry-stack and fill-core method is acceptable. (make sure you include lateral bond-beams and to use structural re-bar).  To this end, remember that in this case it is not essential to have your course lines be level, what really matters is that your wall is solid, and the top course is level.  To achieve this, stack your walls any way you like, and mix a batch of mortar (or get out the diamond saw blade and a scribe line) and set your top course level with itself at the height you want.
Kay Bee


Joined: Oct 10, 2009
Posts: 471
Location: Jackson County, OR (Zone 7)
Sounds like getting a sample of a dozen blocks or even a pallet to get an idea of the quality may be the way to go...
                                


Joined: Jan 12, 2011
Posts: 50
I have worked with both dry stacked and mortared stone,block and brick. Dry stack can work well if done properly,but in my opinion dry its harder to do well. The key to a good dry stack is proper contact-good contact between courses is what gives it its strength and resistance of movement-friction is the key. If you have any gaps between blocks,this greatly reduces the overall strength on the wall and a ¼ inch of stucco is not going to make up for only half the block being in contact with the one below.The problem with dry stack is that you need the first course to be perfect and the blocks to be perfect.I personally don't understand the interest in dry stacking since we have had lime mortar for 2500 successful years.Maybe people are intimated my mortar?I think anyone can learn to mix a good stiff mortar and build a plum and level wall in a day or two.And remember if your wall looks a little rough you can give it a nice stucco coat for aesthetics.

glen
Jamie Jackson


Joined: Dec 04, 2010
Posts: 187
Location: Zone 5b - 6a, Missouri Ozarks
We chose the dry stack with Surface bonding because it's supposed to be much stronger than a mortared wall.  It was also supposed to be easier.  We did several years of research, so we didn't jump into this quickly.  We studied many methods and chose this because so many people talked about how easy it was.

I will say that yesterday, once we got to the 4-7th courses of an interior mass wall, it did get much easier. We don't have many choices for concrete block and tried to do the "right thing" by buying from an individual that owned a block store instead of buying at Lowes.  Though I don't really see Lowes blocks being any better based on how crappy their lumber is. 

It is what it is, we've started down this road with this house.  We could decide to start mortaring courses if we want though.  We've made it past the 3rd course for the whole house and if the interior wall was any indication, maybe it'll get better as we go up. 
Walter Jeffries


Joined: Nov 21, 2010
Posts: 907
    
  18
Our foundation is a floating slab sitting on insulation on top of gravel on top of mountain ledge. The foundation keys to the ledge so the house won't slide down hill. Rebar stubs come out of the floating slab to anchor the wall. On the up hill side we poured the kneewall at the same time we poured the slab all in one piece.

For the rest of the walls and above the knee wall we mortared the first course to the foundation and got that perfectly straight and level. The cedar door frame should be in place to make it easier. Then we dry stacked to the wainescot, the level just below the window sills core filling with concrete and rebar. Use a channel block layer there. We clamped 2x's on and leveled them and then poured to make a new perfect level just below the windows.

Tip: set the cedar window frames in place. We dry stacked up around them to the top where we did another channel block layer and core poured with more rebar. Rebar goes horizontally in the channels and vertically down the cores.

On the walls we then parged with a thin coat of fiber sand concrete to surface bond leaving that layer rough. Then we parged on a thicker coating of white fiber sand concrete to make the interior wall surface. In some places we tinted the white to beige.

For the air tubes behind our wood stove I mortared rather than dry stacking. Mortaring is a little slower than dry stacking.

Here are some photos and posts about what we did:
http://SugarMtnFarm.com/blog/2006/11/first-blocks.html
http://SugarMtnFarm.com/blog/2006/11/lower-walls-up.html
http://SugarMtnFarm.com/blog/2006/11/concrete-block-delivery.html
http://SugarMtnFarm.com/blog/2006/11/cottage-slab-poured.html
http://SugarMtnFarm.com/blog/2006/11/fancy-forms.html
http://SugarMtnFarm.com/blog/2006/11/framing-windows.html
http://SugarMtnFarm.com/blog/2006/11/partitions-half-up.htmlhttp://SugarMtnFarm.com/blog/2006/11/all-walls-rising.html
http://SugarMtnFarm.com/blog/2007/11/one-year-construction-mark.html
steve pailet


Joined: Dec 01, 2012
Posts: 35
Ed Waters wrote:Perfesser, we looked at straw bales, slip form, poured in place, dry stack, and bought the Natural Home plans and video.  In the end we settle on ICF's.  The house we are building is bermed.  We bought are ICF's from ARXX.  They were around 22 dollars a piece for 48" x 16".  Concrete was 92 dollars per yard for 3000 PSI, and rebar for the whole building was around 500 dollars.  Codes are going to become a huge issue going forward.  The spike in building permits witnessed in 12/10 was due to new Federal laws mandating specific r values in building structures.  Traditional construction like logs is going to have a problem going forward.  Our plans were done for pip, and our inspector said if we had left it without insulation shown he would have had to reject it.  If you have any questions I would be happy to try and answer them.  Pictures here: http://luckydogfarm.wordpress.com/
Ed


Had to laugh when I read that a couple of sides of the house were bermed.. Using Ifc against a bermed area is a total waste. the insulation keeps the heat from reaching the earth in back of the wall. The insulation keeps all of the heat that might be captured inside of the house. There is a reason one would want to use concrete block in this situation. That is against earth. The earth acts a heat sink to moderate the inside temperature in the home. There is nothing positive in using an IFC if one expects the house to operate as a passive home.
Walter Jeffries


Joined: Nov 21, 2010
Posts: 907
    
  18
steve pailet wrote:There is nothing positive in using an IFC if one expects the house to operate as a passive home.


Wrong. You've been sucked in to the myth that the earth is cozy. The soil acts as a near infinite heat sink running at about 45°F to 50°F. Most people do not find that to be a comfortable temperature. Connecting to that near infinite heat sink means the heat you produce in your house through solar gain, body heat, appliances, wood heat, etc gets sucked out of your house. You'll never succeed at heating the world. If that earth contact is with wet soil, damp soil or ledge then it is even worse.

Far better to put the thermal mass of the house inside an insulating envelope and then bury as much of that as possible. This means that the thermal mass of the house (100,000 lbs of masonry in our case) is what we heat and the earth is buffering us from the extremes of the climate. This works. This is how our house is setup. I have animal shelters which are setup the way you describe. They're okay as sheds but you would not be happy living there. That's the real world. You want to control the heat flow.
steve pailet


Joined: Dec 01, 2012
Posts: 35
two things that will allow the ground to warm up.. an envelope of insulation that extends out 360 degrees from the house and lots of drainage so the moisture will not wick away the heat.

I guess if you live in Minnesota the ground temps are closer to 50 degrees but here near the tn alabama border we are looking at closer to 60

The other thing is that you have to make use of the ground if you are going to really be passive with high thermal mass..

Using an insulated concrete form.. berming is just about 100% waste of money if you want it as thermal mass. I can understand if you want to use it so that you dont have maintenance on that side of the building.
steve pailet


Joined: Dec 01, 2012
Posts: 35
FYI insulation on both sides of a INSULATED concrete form totally remove any thermal mass from working in the wall. HINT insulation on both sides...
Walter Jeffries


Joined: Nov 21, 2010
Posts: 907
    
  18
Which is why we only insulate on one side, the outside, of the main mass in our cottage.

On the other hand, in our butcher shop there are places where the concrete is sandwiched between insulation. This is part of the structural and thermal design. We have over 1.6 million pounds of structural thermal mass divided into five nested buildings. All of this is isolated from the environment because the world is the wrong temperature - it varies from -45°F to +86°F over the year and I need consistent temperatures in our work, fermenting, brining and storage spaces. Each building within the outer structural building is protected by the building it is inside of. Think of thermoses within thermoses - or Russian dolls. The inner most building is the freezer with R-120 which we can drive down to -45°F using mechanical refrigeration. The cooler that surrounds that gets coolth from that, the brine that surrounds that gets coolth from that, the cave that surrounds that... Planned heat flow. Up in our coolth attic above the refrigerated sections we can store winter in large tanks which we can then thermosiphon connect to the appropriate cold rooms. My goal is to minimize the actual use of the mechanical refrigeration.

See: http://SugarMtnFarm.com/butchershop

and specifically: http://sugarmtnfarm.com/insulaltion-vs-concrete/

but this is getting far away from dry-stacked concrete blocks. When I dry stack, I like to core pour, put in rebar and surface bond with a sand/cement/fiber parge. (There, brought us back to topic... )
 
 
subject: Dry stacked concrete blocks
 
Similar Threads
biochar vs hugelkultur
Monolithic domes
Monolithic Dome
Cold climate foundation choices?
what ever happened to......
cast iron skillet 49er

more from paul wheaton's glorious empire of web junk: cast iron skillet diatomaceous earth sepp holzer raised garden beds raising chickens lawn care flea control missoula electric heaters permaculture videos permaculture books