We finally broke ground on the new house ICF house. It took a while, but we closed with the bank last week. The foundation company put up forms on Saturday and poured 46 piers on Monday. Unfortunately it looks like a few days of heavy rain ahead, so it will likely be at least a week before they can resume work on the remainder of the foundation. There are a total of 98 piers, all 25ft deep. I set up a construction camera to keep a record of the progress. This is my first house, although I did build the ICF storm shelter last year for practice. I'm guessing about a 12 month process for the house. It is a Mediterranean style, 2 story with a tower. About 8000 sqft living, plus a lot of extra space.

I'll be using 6" ICF exterior walls with insuldeck concrete floors. I'll try to post some occasional pictures and updates.






You can see the outdoor hatch/entrance to the storm shelter (grey rectangle). The blue tarp covers air ducts and other utility stubs, and the 5ft diameter HDPE pipe is just above that. A spiral staircase will go down from a closet in the house to the storm shelter. The footprint of the storm shelter is roped off to keep the drill rig and loaded cement trucks off. I really don't want anything weighing more than 10,000 pounds driving over it.

What is the diameter of the piers and is there steel within?

There are 90 x 14" piers, each with 3 strands of #5.  Then there are 8 x 30" diameter piers with 5 strands of #5.   Each with hoops at 12".  The 30" piers are for the areas that span the storm shelter and at the base of the tower.  A bit more weight to bear in those areas.

We have had about 3.5" of rain in the past 36 hours.  That is good for my pond, but not for the construction.

Are the smaller piers hooped as well?

Wait....what happened to that cute little cottage?  :-o

Great project, which state are you in and what block are you using?
We are just starting 2 house's for a client Main/Guest (13000 sq ft), the guest house has 2' thick (29") Big Block from foundation with Insuldeck above and all the rest of the things needed to ride out a nuclear bomb :-).
Good luck with your build,

Why the pier foundation? What is the cost of that type of system?

Posted By ICFHybrid on 10 Jan 2013 08:36 AM
Are the smaller piers hooped as well?

Wait....what happened to that cute little cottage?  :-o

The cute little cottage accidentally fell into the hole . . .

Not really.  Believe it or not I sold it on Craigslist for materials.  Someone came, disassembled the guest house and took everything but the foundation. 

The picture of rebar above is for the small piers.  They haven't assembled the rebar cages for the larger ones yet.  Both types have the hoops.

The house is going up just north of Dallas, Texas. 




The property






A footprint of the house and storm shelter.






Front elevations.

The tower is equivalent to a 4th floor (or 5th if you include the storm shelter), and should give me a great view of the area.

I've got  a question for the experienced ICF guys out there.  I am working on wall and floor penetrations.  Do you guys prefer to sleeve everything out before the pour, core drill penetrations afterwards, or a mixture of the two?

Thanks.

I prefer to use PVC sleeves.  No worry about drilling into rebar that should not be cut.  Get help from the tradespeople as to where the sleeves should be placed.  Save coring only for the items that were not thought of before the concrete was placed.

PVC sleeve everything. What's even better is if you are able to set PVC sweeps (big elbows) that guide the cable or piping in the right direction within the plane of the foam once they get inside.

Don't forget the ventilation penetrations if you have them go through walls.

And don’t forget the penetrations under any slabs (or thru walls) required for make-up-air devices (masonry heaters, fireplaces, etc), exhaust devices (dryers, downdraft ranges, etc), and electrical conduits between guest buildings (home automation, intercoms, subpanel feeds, etc). Must be a massive footing on top of those piers to address what looks like marginal soil loading capacity. What ICF system are you using and why did you choose it?

Ha Ha. How big is the engineering package? I don't need number of pages, just stack it up and measure it with a ruler.....

Posted By Lbear on 10 Jan 2013 11:42 PM
Why the pier foundation? What is the cost of that type of system?

I'm not an expert, but this is my understanding:

The soil around here has high clay content and expands/contracts several inches with rain/drought.  This wreaks havoc on foundations in the area.  For smaller and lighter weight homes, a lot of builders use a post tension system (less expensive).  Some will use drilled piers and a traditional rebar reinforced concrete slab with a small void under the foundation to allow soil movement. 

I plan on living here the next 50 years or so, and due to the size and weight of this house, I decided to do both.  They did test holes down 25ft and never hit rock.  The piers rest on basically a soft shale bottom (bearing capacity of 4-5 tons/sqft) and also use friction to keep them from moving. 

The foundation is 6520 sqft, and cost including engineering and installation came in at $82k.  I talked/met with several different foundation companies before deciding on one.   I've been really impressed with my foundation engineer / company.  So if anyone in the Dallas area is looking for someone, just send me a message.

Install a few "just in case" PVC sleeves in strategic locations for possible future use. Document their location real good, fill'em up with foam, and finish the walls inside and outside. Ten years from now when you need to run something through the wall it'll be a lot easier.

After about 10 days off for rain, we had a good week of construction last week. The remaining 52 piers were installed, the plumber came in and did his thing. The foundation crew also poured a small "working slab" for a large beam spanning the storm shelter. That will transfer the weight of the front corner of the house to the piers instead of onto the shelter below.
 


They are looking to pour the slab in about a week from now.

Thanks for the pics and updates! This will be a great project to follow.

Will the home have any 2nd story decks or balconies?

Posted By ICFHybrid on 11 Jan 2013 11:16 AM
Ha Ha. How big is the engineering package? I don't need number of pages, just stack it up and measure it with a ruler.....

Just got all the coffee off my monitor and keyboard, my mistake for taking a sip right before reading that question.. Hahaha Nd, really cool project, thanks for sharing it with all of us! You have hit many man dreams with this one. Private lake, man cave on crack, and a beautiful house.

Lbear - We have a couple front balconies and a lot of rear balcony / deck space (to take advantage of my pond and get a view of a nearby lake.  The 2 front balconies are just about 100sqft each, but I have over 1000sqft of rear 2nd floor balcony.

All the deck/balcony space is in concrete (Insul-deck).  This did present a big thermal break problem, but I think we came up with a decent solution.  Basically the outdoor joists will be continuous with the joists inside the house, but the outdoor concrete slab will be free-floating and thermally broken from the joists.  I'm using the 12.5" insuldeck forms, which gives me pretty deep joists.  All the outdoor decking is fairly short spans (less than 12'), so those joists are over-kill.  The plan is that we will pour the outdoor deck joists with all the indoor decking pour.  However, we will leave the cap/slab off the outdoor deck.  We will then go back, spay a couple inches of spray foam on top of the outdoor joists, then pour a 3-inch free floating slab on top.   The engineer gave the okay on the design and I think it will be a fairly good thermal break. 

BrianBarron - Definitely living the dream.  I'll be the first one to admit that I've been blessed.  I've got good health, a great family and a steady job.  I do put in way too many 60-hour work weeks at my real job, then come home and put another 40 hours into my home projects.  Some day I'll kick back and actually enjoy some of what I have.  Until then, I'll just have fun building my dream. 

I spent the last several days putting in my back-up water supply and connecting all the utility conduits, plumbing, and air ducts to the storm shelter.  I figured a back-up water supply would be good to have in-case we got thirsty during a storm, or if a tornado knocked over the local water tower. 

We have a couple front balconies and a lot of rear balcony / deck space (to take advantage of my pond and get a view of a nearby lake

Wait, wait...., you have a pond of your own AND you want to get a peek at a nearby lake? Sheesh. Some people are never satisfied.... ;-)

Is a backup water supply just an inline reservoir that stays filled during normal use, or........

Getting ready to pour tomorrow. I'll post an update ad some pictures later.

Quick question for the people out there with ICF experience/knowledge: I'm doing foundation dowels every 16" OC. They are #4 rebar. How far out of the foundation do they need to stick up? I've seen / heard numbers from 8" to 24". Inspection is already done and I'm not in a city limit, so there are no code issues. I just want to know what others recommend. It is central Texas, so there are no seismic issues.

Thank you!

IBC says 40 diameters for lap splices.