Catvader,

If your house is going to be built on 15' pilings, I think that ICF would be exceptionallly challenging to build. The weight of the concrete walls would be substantial. ICF makes tremendous sense esp in OBX (I live in VA) because of the threats of hurricanes. If you really want to find an ICF builder that can assist you, I'm sure I could help you investigate that, but it goes back to the pilings. I think that you will encounter a problem there.

renangle

as distributors and state certified builders we have been planning and building in coastal areas with icf walls since 1995, and with insuldeck floors and roofs since 2000. our builders and distributors have built 2 and 3 stroy elevated structures on all types of foundations. we cover the south east and have icf distributors in virtually all states who can help you with your project.
if you send me an email i'll be glad to put you in touch with experienced distributors architects and engineers, and email you our cd with hundreds of project pictures and techinal information.
[email protected]
depending on soil conditions you can put a multi story icf structure on all foundation types that are designed to handle the weight of the structure.
ie:
augered cap rock with 4'x24" concrete plugs and columns above...(not on obx)
all others likely:
jetted or augered timber piles with concrete pile caps and grade beams/concrete columns above...
augered concrete piles, prestressed, water jetted or driven concrete piles...
helical screw piles...
and many more....
a capable structural engineer, familiar with concrete design is the key here.
as is finding out beforehand what piling methods/contractors are availbable on obx.
concrete availability should not be a problem there.
peter

So you think it comes down to a competent engineer vs. architect, builder?

Catvader

You have intrigued me with your idea so I decided to investigate it a little for my own entertainment. I talked with an engineer and architecture firm who is familiar with that area and could theoretically work with you if decide to move forward. That being said you will have a few challenges. First you would need to hire a geotechnical engineer to test the soil and figure out where the friction numbers hit the right ratio to allow the pilings the capability of handling that load of an ICF house. Part of that will be determined based on location...if you are in Duck it will probably be very difficult to do, but if you are near Kill Devil Hills it would be bit easier. You would need a very talented structural engineer, geotechnical engineer, architect, and ICF professional and probably a little luck.

By the end of the day, the answer to going ICF is yes, you probably could. The engineer and I both agreed that taking on a project like that with so many challenges would be expensive as a mofo! That is a summary of our discussion. If you would like to open that door, I could put you in touch with the professionals I spoke with, but you are going to need a heafty checkbook when compared too traditional construction.

Thanks....renangle

I also will talk to my engineer/ architect about your project.

We are finishing up a house on the coast in the Florida Panhandle. We drove 20' long timber pilings with 12" tips to below grade and poured pile caps and a self supporting grade beam(this allows the house to survive if the sand washes away). From there we used 10" core ICF to build columns up to a 10" by 18" elevated beam, again using 10" core ICF.
Then we used 6" core ICF for the walls. We were able to use the extra width of the 10" core beam to bear the 1st floor trusses. By using this method we were able to have much larger spans and much more open area underneath than if we used wood. For instance we have some spans of 20'. It really opens up the underneath of the house and makes it much more functional.

The system works great and is perfect for hurricane prone areas. The only drawback is that it can get costly if you have a bunch of corners. Generally, due to the weight of the walls, you more than likely will need to have a piling for each corner you design into the house. With wood you can have a lot of bump outs or overhangs that you might not need to have pilings under. We were able to keep ours to 6 corners. If money is not an issue than this is not a problem.
 

Do you have any pictures or drawings you could share?  Did the 6 corners include deck corners or did you do the deck differently? 

An aside, of course money is an issue! Unfortunately, I'm finding that the products that last are only in the price range of the people that could afford to rebuild anyway if it washed away!  I'm frustrated, but I haven't given up yet:)

The 6 corners were for the house only. We used full length (30 foot) wood pilings for the porches.  We did this to save money. The wood pilings are plenty strong enough to support the porches just not the ICF walls. I can probably email the pdf drawings if you are interested. I think it would show all the details.

I'm interested.  Pdfs would be great if you don't mind sharing.