Wow, take a photo tour of this ICF project. It is one insane undertaking, it should be completed by September 2012:

Casa Bella Verde

That's what I'm missing - a Project Director. ;-)

I didn't see any vibrator in use in that short video clip where they were topping off the round wall.

Posted By arkie6 on 01 Jul 2012 12:39 PM
I didn't see any vibrator in use in that short video clip where they were topping off the round wall.

I observed the same. I believe that was a 8" concrete core ICF but there are always air pockets in the concrete so you would think they would vibrate it to get the air out. I believe the guy running the vibrator was taken out of the shot during filming. There is no way that they would not vibrate that wall and that project. They went overkill on everything and to cut this corner (not vibrating) would not make sense.

There is a good chance that no one involved with the project knew that vibrating the concrete was important.  I still hear that there is nothing wrong with adding water to concrete so that vibrating can be eliminated.

Opulent, but by no means GREEN, by my definition anyway.

Posted By MikeSolar on 01 Jul 2012 06:35 PM
Opulent, but by no means GREEN, by my definition anyway.

I agree the home is not modest and overkill for a family BUT you have to realize that someone with a lot of $$$ is going to build a mega-mansion. I would rather have then build a mega-mansion utilizing green practices than use energy wasting methods.

We cannot force people to build and live in small rectangular homes, limiting them 600 square feet per occupant. I give them credit for building a structure that will use a lot less energy than a drafty and poorly insulated home. The home will have PV solar, so that is also a plus.

Posted By Alton on 01 Jul 2012 05:47 PM
There is a good chance that no one involved with the project knew that vibrating the concrete was important.  I still hear that there is nothing wrong with adding water to concrete so that vibrating can be eliminated.

That is scary. One only has to read & look at the voids in the walls of that ICF study they did and that is enough proof to show that vibrating is necessary.

ICF Void Study

You have to admire the self-delusional abilities of someone who can build a 7500 SF house with attached (by skybridge) 1500 SF guest house and then assume the mantle of "friend of the earth." Only a power plant could repay the embodied energy in all that concrete surplus to a regular sized home. What's more, she has bought into the "ICF performance equivalent to R50" study (more of bad joke really.) Quick, there must be something we can sell to this woman.

Just think how much more energy could be saved if the exterior foam was just two inches thicker.

Posted By Lbear on 01 Jul 2012 06:51 PM

That is scary. One only has to read & look at the voids in the walls of that ICF study they did and that is enough proof to show that vibrating is necessary.

ICF Void Study

I can't resist any longer. Here are three pictures showing in a real world situation concrete that was not vibrated. Yes, there is air entrained in the concrete, particularly in photo 1. Is it a problem? Not in my book. Why? The concrete slump was on the order of 6 in, had aggregate less than 1/2", and was a 5 bag mix to facilitate flowing.

Taking into account all live and dead loads, the load on the footer in the most heavily loaded sections of the wall was such that I calculated I needed an 18" wide footer based on a soil bearing capacity of 1500 psf. So, for the 6" thick wall that translates to 4500 pounds per lineal foot. 6 x 12 = 72 sq inches. 4500 divided by 72 is 62.5 pounds per sq inch. Even if the concrete achieved only a 1000 psi compressive strength, which I think would be a ridiculously low value, that is a safety margin of 16.

Concrete, by itself, only has strength in compression, and I have no fear that the concrete in my walls has insufficient compressive strength to hold up all the concrete above it plus the roof, floors, and interior finish. I am not the least bit worried that my concrete walls are going to crumble because of entrained air.

My house is only one floor, so for a two or three story house I would not be so cavalier about not vibrating. In any case, we did vibrate below windows and in the corners to make sure the concrete flowed into the spaces as required.

I'm not dismissing the value of vibrating, but neither do I think it is so critical that if you miss vibrating a cubic foot of concrete your house is going to fall down.

I will admit that the entrained air is undoubtedly one reason why my concrete volume calculations came out about 6% higher than the actual volume poured.








This is what happens when the dry wall contractor doesn't think a shield plate is needed over AC lines!! He did not get paid to patch the dry wall after the tube was repaired!

You have to admire the self-delusional abilities of someone who can build a 7500 SF house with attached (by skybridge) 1500 SF guest house

That's only an average of 4500 sf per unit. That's not much bigger than some of the other big ones we see here. :-)

I can't resist any longer.

That's right. There is way too much angst here about vibrating. I don't believe it is something you do or don't do as a matter of habit. You do it if you need it. The best plan is to watch the concrete flow and go slowly. I had way more steel than any of the other builds I have seen and we didn't vibrate except in a few special places. Haven't found a void yet.

Posted By Lbear on 01 Jul 2012 06:46 PM

Posted By MikeSolar on 01 Jul 2012 06:35 PM
Opulent, but by no means GREEN, by my definition anyway.

I agree the home is not modest and overkill for a family BUT you have to realize that someone with a lot of $$$ is going to build a mega-mansion. I would rather have then build a mega-mansion utilizing green practices than use energy wasting methods.

We cannot force people to build and live in small rectangular homes, limiting them 600 square feet per occupant. I give them credit for building a structure that will use a lot less energy than a drafty and poorly insulated home. The home will have PV solar, so that is also a plus.

I don't ask people to stay in 600ft2 per person homes although that is not so small as it seems. Many of the post war bungalows around here were maybe 800ft and people were quite comfortable. There always was and always will be big houses for the rich, I just wouldn't applaud the owner or builder and make them feel like it OK to build these testaments to ego.  The builder of that house really only puts in solar and wind as a token gesture. 

Regarding vibrating. Any voids within a wall will most likely never rear their ugly head UNLESS they are put to the test. This would come in a form of a natural disaster (hurricane, tornado, earthquake). Places like California, Christchurch, had concrete structures that were standing and looking just fine for years until they were put to the test. That is when poor mixes, voids, bad engineering, poor reinforcement, will come back to haunt you.

If the Portland Cement engineering gurus and the top dogs in the ICF industry state that one should vibrate, I will follow their recommendation and vibrate. They paid a lot of money to conduct their tests and when you see the results of them NOT vibrating and the huge numerous foot long voids across the ICF walls, it is eye opening to say the least.

I guarantee you their are plenty of huge voids hiding beneath many ICF walls out there. Most people will never see any adverse effects UNTIL it is put to the test. Then it will become apparent that it was not done right. At a minimum one will experience some minor structural damage, worst case scenario the structure will fail and kill the occupants. Paying a guy $10 a hour while pouring to run a vibrator down the wall is cheap insurance in my book.

Posted By MikeSolar on 01 Jul 2012 09:34 PM

I don't ask people to stay in 600ft2 per person homes although that is not so small as it seems. Many of the post war bungalows around here were maybe 800ft and people were quite comfortable. There always was and always will be big houses for the rich, I just wouldn't applaud the owner or builder and make them feel like it OK to build these testaments to ego.  The builder of that house really only puts in solar and wind as a token gesture. 

Look, I won't judge them as I don't know them or their moral standing. Hypocrisy is everywhere and we are all guilty of it during our lifetimes. I've known people who lived in 400 sqft apartments that would pour motor oil down their sewer and run the water all day long because they were not charged per the gallon.

The point of this thread was to show the architectural achievements of this home. I don't even know who the owner is and really don't care to be honest. I do give them some credit for at least trying to build it with energy efficiency in mind.

I am building a similar home for a client, possibly bigger, three stories ICF, one cannot guess as to the reasons why people build big, however, in my case the client helps many people by providing a place to stay for college students and such, plus they are providing many jobs for the community. I for one don't begrudge someone because they can build big, many of these people are in their position because they have worked hard and helped others along the way and are now blessed because of it and by spending their money instead of hoarding it, provide jobs for all the rest of us.

Regarding voids in the wall, what is the best concrete mix for a 5.5" thick wall, seem to have trouble with the local suppliers getting the mix right

What percentage of fly ash can they use?

The builder of that house really only puts in solar and wind as a token gesture.

I don't see it as token. Any amount of solar and wind that they put in represents fossil fuels that don't have to be burned. The project description seems to imply that they are going for near self-sufficiency which is a whole lot more than most people are willing to do. In any case, there are all kinds of people, some of whom produce more than others and as a consequence, they might consume more.