Hi, nice to meet you :)

I live in Argentina. I'm looking for building a two stories house with ICF blocks. Here ICF is not a common construction method. As long as I know, there is only one brand of ICF blocks: Isolbrick. I think their previously went by the name of Sistema Exacta, which also sells in Chile.
The blocks that Isolbrick provides are quite different at what I'm used to see in this forum and other forums of USA, Canada or Europe. Here is the technical data sheet. It's in spanish, but I'm most interested if you can take a look at the pics rather than the text. As you can see, this blocks don't have that plastic web ties that most USA manufacturers show in their products. This is a four side foam block.


So, to start, some questions:
1. Could you advice me in the pros and cons of this design? I'm particularly concerned about not having those plastic ties, and how much of a problem it is.
2. The concrete would have to be poured manually, and not by a concrete pump. Could this be a problem for the overall quality of the construction and insulation?
3. As I said, here in Argentina we have little experience with ICF building, so I'm not sure I will find contractors with great experience, just with a few houses on their shoulders.. Again, how can this impact on the overall quality and the expected final insulation?
4. This house will be built in the Patagonia, in a town (Bariloche) with a climate very similar to North California / South Oregon (warm-summer Mediterranean climate, Csb according to the Koppen climate classification). Winter nights should be in average -10°C. Isolbrick offers 3 size of ICF blocks, with K values in the range between 0.641 W/m2K and 0.314 W/m2K. Do you thinks this are reasonable values of insulation for this region?

Thank you very much for your help

Well it looks as if it produces what we would call a waffle grid concrete wall. They work, but my only concern is in how well the concrete gets consolidated and fills in all the way to press up against the roof of each of those horizontal passages. Since the vertical passages are smaller, once you add rebar, the ammount of room to get a vibrator in there to properly consolidate the wall gets pretty small. These properties make the pour more difficult and the expertise required to get it right more critical...

What seismic zone are you in? In the US, I think waffle grid pattern walls are not permitted in seismic zone D because they are not as resilient in a shake. They are also not used in the lower wall/basement wall of a two story masonary wall...

The only issue really with the lack of crossties is that you will have to tie any structure back into the concrete, unless they buried screw strips in the foam(sorry don't read spanish). Most of their photos show stucco or plaster finishes, which may be more common there than the traditional sheetrock inside and board siding outside used in the US. Without all the crossties, those type of finishes would be a lot more difficult to apply...

Hi ronmar,
Thanks for your input.

a. I'm not 100% sure about seismic zones categories. In Argentina is "category 2". Most of the info I get is that my lot is in a "moderate seismic zone", I think something like C category in America for my understanding.
b. I didn't quite understand you. I'm still considering the possibility of a basement. Are you saying that this kind of blocks doesn't allow me to do a basement and two story?
c. I didn't understand you again :) Which are the ones harder to apply? sheetrock & siding? or stucco & plaster? Here, stucco/plaster are the most common finishes, but siding is popular too.

Again, thanks for your cooperation.

That would be wrong. Screen grids are allowed for basements with the required rebar. Inaki we use in most jurisdictions in this country the Prescriptive Method as the guide for rebar placement in an icf build. You can find it online. I think the section you would be interested in is section 3.9 table I 25. It gives you the requirement by soil type as well as back fill height. You could install sheetrock even if there are no webs. Adhesive will work. Synthetic stucco readily adheres to eps if you rough it up. With that said I would never do a screen grid by using a portable mixer and a bucket.. In order for this form to work under ground it would have to be a continuous pour with a 4000 to 5000 psi mix with out adding too much water.

Thanks smartwall.
Just to be clear, you would never do a screen grid with portable mixer and bucket for underground (basements, below grade), or for above grade neither?

Right. The screen grid is the hardest icf to attain a consolidated concrete wall. That is the reason they have fallen out of favor. They along with the waffle grid are the original icfs. Flat wall is the more common form but even they can result in voids if not poured and consolidated properly. Screen grid relies on a post and beam with the rebar connecting them. Any voids become critical. Above ground is less critical because you are facing no back fill pressure. I still wouldn't do it above ground. I hate to say it but CMU with eps attached would seem to be the better option if no pump is available along with the proper mix.

Thanks smartwall. This is the kind of information I am looking for.
I'm a little disappointed, as ICF looks great for building, especially against our standard building systems (hollow clay bricks!).  I am not opting out of this Isolbrick's ICF, but I will definitively be looking for other building systems. CMU was what I originally thought of, but ICF seemed like the easiest way to achieve air tightness. I will search for EPS attachments available here in Argentina.

Can the hollow clay bricks be insulated with expanded polystyrene (EPS)? And then cover the EPS with stucco? Would that be strong enough for your area?

ICFs are always a better choice and are a good choice in Argentina. It is tough for us in the USA to understand how things are done. But a flat wall is not needed when you reinforce the concrete the way they do. Rebar tying is an art there. There main building system for residential is concrete and masonry with cantilevered walls and structural concrete floor systems.

We are manufacturing a composite ICF in the North of Argentina, Salta. Salta is an earthquake prone region and the engineer we hired ran software testing a model house of our ICF. Our composite ICF is column and beam (columnas y vigas). I chose a cementous composite ICF because manufacturing an all EPS ICF in Argentina is expensive and the composite is better suited for stucco and plaster. I designed a column and beam or "screen" system because concrete and placing is expensive, also there are few basements in the North. The screen system more closely match the frame of reinforced concrete that is used in that region.

I was there in February and March preparing the land and starting a house that will be made with our ICF.

Sounds like a line pump business would be a hit

Posted By smartwall on 07 May 2016 08:48 AM
Sounds like a line pump business would be a hit

I don't know. I hired an excavator to grade and pull stumps. He would have charged $32 hr to dig for the foundation. That is equal to about 1.5days of a laborer with a shovel. The crew I hired to put in the footings dug by hand. Also not much ready-mix gets used, due to the cost. So for an ICF wall, I can see them mixing in a small electric mixer and using buckets to get it in the wall.

Hi ICFconstruction,
Thanks for your reply. Is that composite ICF commercially available here in Argentina? Do you have any link to share, or maybe some contact info?

Cool to know that you are working in Argentina. It is very interesting for me that someone experienced both in ICF and building in Argentina shares his view on working with this construction method with local resources (workers, methods and materials).  I would really appreciate any of your insights or opinions about this.

Thanks again.