Frequently Asked Questions of ICF 

You’re very welcome

I would be interested to hear more about that. Please email me when you do it. kody@uptokode.com.

Very much appreciated this! Thank you my friend!

Hi Kody, I have a few questions I hope you might be able to help me with: - 1. I heard someone talking about how ICF negatively impacts the positive thermal properties of the concrete, due to the interior face of insulation. Is there any truth to this? - 2. Is use of drywall required or can T&G wall boards (for ex) be installed directly onto the interior walls? Reason I ask is concrete should negate fire code requirement for drywall… but, does the interior face of (flammable) foam then re-require the use of drywall? - 3. You mentioned ICF performance against natural disasters. I’m in tornado country, and I tried to find testing data on ICF (and poured concrete walls in general), but couldn’t find anything that made clear how 6”/8”/10” concrete walls performed in tornado conditions (failure at given wind speeds). Do you have info, or data you could link or direct me to? - 4. I’m looking at building a fairly small home that is based on 16’x16’ modules. Something I’ve thought about is where 3 modules are connected linearly, at the middle module which wouldn’t have 2 sides of exterior walls, having 2’ of wall (via T-blocks) return into the interior to act as additional structural rigidity. If there’s structural benefit in doing this, it wouldn’t require much extra cost. Thoughts? Thanks!

That would definitely be secure. I’ve always just attached to the ties.

That’s too bad. Sometimes I feel like the ICF is so simple that people think it’s needs to be more complicated in order to have so many benefits. Build with the ICF and they will understand later the benefits. When it’s super comfy and quiet. Show them your utility bills, etc.

I greatly appreciate this!! 🙌

I will. Thank you. Go ICF for the future !

Yes I will add it to the list.

No I haven’t done Geothermal yet. If I do you can bet I’ll video it.

I’m a stickler for drainage plain so I would NOT apply acrylic stucco directly to the foam.

This is how I would do it: -synthetic paper against foam. (Tar paper will eat the foam) -2 layers of tar paper on top (whatever is local code for drainage plain) -proper water shed and flashing details to allow drainage behind the stucco -wire and screw to the ties -scratch coat and brown coat of cementious stucco (keep super flat) -acrylic finish coat last. Floated or texture finish depending on what you like.

I think “Tiger Claw” is one brand. Go to a stucco supply store and they will have them. It’s like a big wide concrete trowel with carbide on it.

I don’t know anything about it but you definitely need large volumes of concrete that will flow into a wall assembly like this.

@@uptokode It's very tough to mix thoroughly even for a post-hole.

We install an LVL top plate that is bolted to the concrete. Below that is a strip of acoustical sealant and PL premium. If you want to reduce bridging, use a slightly narrow LVL, keep it flush to the exterior and then foam the interior side to stop transfer at the LVL.

I see your concern. I would use the Watkins hanger and if you need advice on install just email me. kody@uptokode.com. But if you are more comfortable framing walls you can do that too. Makes sense for a smaller place.

You have a point. But once you start with the double stud wall, in my opinion, you still don’t have anything close to an ICF wall, you have complicated the build, more lumber used, still susceptible to air infiltration, still susceptible to rot, no thermal mass, no added strength, and I bet the exact same price. I say this… build conventional if you want the lowest cost possible. If that’s your goal. If you want efficiency skip all the fancy BS and go straight to ICF. The benefits are substantially better than any modified, fancy system out there. No other system can match the benefits and simplicity that ICF offers.

I simply like Nudura. For multiple reasons. If you look at the price of the block it may appear to be more than others, but they come collapsed (saves trucking and space), they clip together (less labour installing), they are reversible (less waste). So at the end of the day the block systems are all very comparable in price. Shoot me an email. kody@uptokode.com.

I’ve seen them around. They are just south of me. I don’t like the 6” centres. But otherwise I’ve heard great things about the block. The ICF system is what I promote most.

@@uptokode another wonder…my wife and I are in the process of getting plans for a house drawn up. Intentions are for ICF to the rafters. I’ve researched various methods of attaching floors to the walls and now my preliminary drawings have something I’ve never seen but seems to be common here. The draftsman put in a taper block at the top of the basement wall and then transitioned from 8” to 6” for the main floor. Foam was removed from the interior of the bottom course of the main floor walls and a 2x4 sill plate fastened down with a ledger set on it and fastened to the exposed concrete where the foam was removed. Apparently they spray foam the inside of the ledger between the joists to bring the r-value up. It makes me a little uneasy

That’s way to complicated. Email me if you need. kody@uptokode.com. Don’t transition block widths. Use Watkins hangers or the Simpson system. Burmon has a hanger too. Keep it simple. I think you know that.

Congratulations on your build! It would be ideal to insert the 1/2” plywood for a TV.

Yes absolutely! It’s disaster proof. Rated for very high winds. Good for earthquake zones. And performs very well in hot and cold climates.

Thanks for the great question. I don’t know a lot about ICCF but I do know this about ICF. -ICF is the only true monolithic wall. Strongest by far. Wind and tornado proof. Blocks of any kind cannot compete -ICF is very air tight and the easiest to achieve this too. Our last house was 10X more air tight than typical homes in our area. -electrical is easy in ICF and no need to pre-determine or run anything in advance. Get the ICF and the shell done… worry about electrical and mechanical later. -The ICCF doesn’t sound bad actually and I don’t know much about it.

Do you mortar the ICCF blocks together?

The information that I have seen is that you apply foam spray to lock them in. So no mortar. Also they claim 250 mph wind resistance. Thanks for your reply. With concrete being about $220usd delivered where we will be building…I like that the iccf system uses about 25% less concrete.

I would run the math on the cost difference. ICF is still superior and you will never lose air tightness. I don’t like walls that connect or aren’t seamless.

If you needed 50 meters to do an ICF house, to save 25% of concrete that’s only $3375 or around 12 meters. Not worth the sacrifice in my opinion. But I do appreciate your thoughtfulness and if you go with ICCF you’ll still be doing better than most.

You’re right about that.

You could do an Icf roof. But imo a standard truss roof with hurricane straps and Icf walls should be fine for anything you throw at it. Solar panels I'd recommend to ground mount them if possible.

Did I comment to you in other posts? You can always email me too. kody@uptokode.com. For a sloped ICF roof I have NO experience but have heard quad-lock has a great system. If you want a flat roof (super low slope) I would suggest the “Fortruss” system. It’s fully insulated with different configuration of beam sizes and depths available. Then you pour a slab on top (garage floor OR flat roof).

Thanks for your insight. I would add… don’t use the tiny crappy little hurricane ties that only bit into the bottom cord of the truss. I would strap right over top of it. That’s the proper way.

I’ve only used 6”. Even on some crazy builds. Sometimes you need an engineer to spec the rebar for higher backfill.