When we were pouring the walls of my house I grabbed the vibrator and started to vibrate. The concrete contractor said not to do that, the risk of blow outs was too great. He used the vibrator at the corners and to flow the concrete under the windows. He ordered the concrete so it would around 6" slump out of the hose and with 3/8" aggregate. He had the plant make it a 6 bag mix. The heavier cement content aided in the flow. I found no voids anywhere with a probe or when putting anchor bolts into the wall. I'm sure the concrete had some air entrained in it, but I have to ask, "So what?"

Let's look at the impact on strength by entraining air, having voids, or using a high slump mix. The target is generally around 3000 psi or greater, right? As we all know, concrete has strength only in compression. On my house the gable wall at one end is 14' high. The total load, live and dead, at the footing is roughly 4500 psf, max. That is equal to 31 psi! Even if the concrete strength is reduced to 1500 psi by the air, voids, and slump, it still is 50 times greater than the load it is bearing. Why all the fuss about the effect of air, voids, and slump on concrete strength? Lateral strength is provided by the rebar and that changes very little regardless of concrete strength.

Based on my experience with one house, I say flowability is the paramount parameter to be concerned with. Vibrate as needed, but don't get wrapped around the rebar about vibrating. It ain't worth it.

Here are a few pics from the inside. I haven't put on the outside ladder hatch or put the ladder in place yet, but they should be easy to do. I need to catch up with everything else around the house that I've put off doing the past few months. The ladder well should be big enough to get full sheets of plywood or sheetrock through.

Looking down the ladder entrance.

Looking up from the inside of the ladder room.

Looking from the ladder room to the main area. You can see one of the wind resistant doors.

A couple shots from inside the main area.

A couple shots from the stair room (will connect from the house through the 5ft diameter HDPE pipe).

Finally, a shot from another room that has access to the sump room.

The whole structure consists of one large center room plus 4 smaller rooms. Two of the smaller rooms are for entry/exit with the spiral staircase or the ladder. Overall, I think I have the best storm shelter on the block.

You wouldn't happen to be same guy who's building a bomb shelter home inside the mountain northeast of McCall, in central Idaho, would you? It's not ICF though. It's said he's somebody from Texas.

No, I actually live in Texas and built it in Texas. Don't think I have ever been to Idaho.

Posted By nd96 on 02 Dec 2011 07:47 PM
No, I actually live in Texas and built it in Texas. Don't think I have ever been to Idaho.

I didn't really think so. You're building your shelter for a sane reason, hurricanes & tornadoes. It's rumored the guy building the bunker in the Idaho mountain is a Texas oil baron who wants to escape an eventual nuclear bombing. The garage, or warehouse more so, part of it is inside the mountain and large enough for at least a couple of semi truck trailer units. We see him as plumb crazy.

Sometimes I think this is a dangerous forum. Here we have a guy (dmaceld) who has 1070 posts but has apparently been involved in one ICF house construction posting like an expert, contradicting the entire concrete industry and decades of research.

If he were a professional consultant I'd say -- I hope your errors and omissions policy is up to date. For the folks reading this forum to gather real information, please bear in mind that there are a lot of amateurs on this forum who post like experts but are actually propagating myths, conjecture and outright falsehoods. Anything you read here should be verified by a licensed professional, and remember, building an ICF house is not a do-it-yourself project. Sorry to be the wet blanket at this party.

remember, building an ICF house is not a do-it-yourself project

Hmmmmm.... Is that a new industry policy or your professional opinion?

Professional opinion, of course.

I think it's important for the green and innovating building industry to keep hearing from non-professionals. It's also lucky for the ICF industry that I decided to build with ICF despite the opinions of the first 5 or 6 "professionals" I sat down with.

Posted By BrucePolycrete on 03 Dec 2011 09:12 AM
  ...and remember, building an ICF house is not a do-it-yourself project.

This very thread disproves your statement above.  Go back and read the title and first post in this tread.  ICF are easily a DIY project for someone that is well prepared.

Posted By BrucePolycrete on 03 Dec 2011 10:23 AM
Professional opinion, of course.

What profession do you hold a license in?  Based on your history of posting here, I though you were a Polycrete ICF salesman.

Posted By ICFHybrid on 03 Dec 2011 11:04 AM
I think it's important for the green and innovating building industry to keep hearing from non-professionals. It's also lucky for the ICF industry that I decided to build with ICF despite the opinions of the first 5 or 6 "professionals" I sat down with.

ICFHybrid, (and arkie6)  I must agree with you regarding the non-pro contribution and how important it is ---  I think it's huge to the overall momentum of the industry.  Demand for better ultimately pushes the professional to add to his toolbox - they usually dont' want to at first.    I've worked with (about 25 or so do-it yourselfer homes) over the past few years and they have all turned out great.    They require different levels of attention depending on construction experience from almost none to a disproportionally huge amount.   It seems that they are the guys that are the proudest of there homes and each will result in a couple more homes -- EVERY TIME.

I am required to provide training and/or onsite support and cannot sell ICF to some guy that wants to skip training and give it a try.   In some cases I end up actually doing the install (or suggesting an installer in our network) but for the most part these guys are the thinkers out there that are pushing the bar up for the professionals.   Okay, before you knuckleheads start throwing tomatoes.... I am saying they push the bar up because the professional is being required to add to his quiver and get out of the norm.

The do it yourselfer typically has a tough time convicing the 5 or 6 professionals framers etc. to try building to a higher level.   Sometimes they just have to take things into their own hands.  Sometimes a 3000 square foot install takes a month instead of a week but I don't really see the harm if the right support is provided.   They are the proudest home owners and the best sales persons out there.  Regards.

Arkie, I'm president of PolycreteUSA. We hire licensed professionals.

The point of my thread was not to say that any amature out there can build with ICF's. I would not endorse that and feel it would be bad for the ICF industry by promoting sub-par construction. However, the right person with some hard work and good support (my engineer was a significant help with the whole process. He's got extensive ICF experience and posts frequently on this board), ICF construction can be done by a DIY person. I sincerely believe ICF's give you a vastly superior product compared with traditional building methods.

I know my limits, so that is why I will be looking for a professional to build my house. But now that I do have a little first hand experience and am more familar with the whole process, I think I will end up with a better product from the professional as well.

Posted By BrucePolycrete on 03 Dec 2011 03:45 PM
We hire licensed professionals.

Please read my response in the new thread I started just for this issue.

I can attest to the fact that nd96 is an outstanding example of how well a DIY-er can build with ICF... or anything for that matter. He read up on the intricacies of it, asked lots of questions, (listened to the answers) and dove into it. The results were about as good as any I've seen on the functional side. Proof that this indeed CAN be done by a non-professional. A tip of the hat to him.
Professional? nd96 is a licensed professional, just not in construction. And I don't think Texas ICF or insuldeckflorida are licensed professionals, but I've seen their work and they are both at the top of the heap, along with others.

This industry is grand, and it thrives on the contributions of many diverse, dedicated, individuals. Ain't it GREAT?!

Sorry to be late to the party, but I'm planning on building something almost exactly like this, so it's an awesome post, with the photos and all. I just had a few questions for the OP, if he's still around. Why did you chose to use ICF for the ceiling of the shelter, instead of simple concrete and rebar? What is the advantage of it? Seems like you put a ton of rebar in anyway. Also, how much would something like this cost me, as I'm older and not able to do much of this myself. Possibly an extra 10k for labor? Anyone care to give me a rough estimate, I'm guessing $75k-$85k range? Mine couldn't be this deep underground, maybe just 6 feet. One idea I have is to install on the side of the hill and actually have the front exposed, more of an underground house. I could always modify that if I needed to in a crisis to conceal the front. I'm a total newcomer here and to this community, so thanks!

(This would be in the Portland, OR or Arcadia, CA area).

Hello nd96:

This is 'off topic' but how were you able to post pictures? Thanks

Don't use the "Quick Reply" box at the bottom of the window. 

Click on the "+ Add Reply" button below the bottom left side of the last post.

At the bottom of the window is the "Attachments" folder.  Open that folder.

Click "Browse..." and find the picture file that you want to post.  Note the size limitations on the picture file.  I think the file size has to be <100 kb.  You will most likely have to reduce the size of your picture file considerably using Windows or your camera software.  I never reduce the original file but create a second file with "small" at the end.  You will need to do this before uploading the photo or you will get an error.  Once you have selected the file, Upload it.

Then place your cursor where you want to insert the photo.

Then click the "Insert Image" button next to the file name.  Like so.  Then submit.

Thank you.