Due to narrow internal building dimensions I am considering using ICF forms (Fox Blocks) and pouring 4" concrete walls for internal partitioning and then removing the insulation from the finished walls. (Main reason being it is very difficult to find 4" thick concrete wall snap-ties for conventional plywood forms.) I have read where one can strip the insulation off finished walls. The question I have is what do the walls look like after stripping the insulation off? I do not plan on applying any other finishes after stripping. Does anyone by chance have a picture of a result? I would think the concrete surface would be smooth and clean except for webbing remains... Thanks for any replies.

Nudura ICF Block Has a block with plywood on one side that is made to be removed other wise the concrete would look like the inside of the block your using and stripping that foam is a lot of work

Hello Strong Wind Builders and thanks for the response. I had looked at that Nudora single-sided plywood product. Great idea. I need both sides stripped though. If that product allowed for both sides being plywood it might work well. The cross section of a portion of the building is attached and hopefully viewable. The outer/exterior walls are 10" ICF blocks the inner walls are ideally only 4" of poured concrete thickness. In case not viewable, inside the exterior walls, I have a 12'x12' vertical shaft. Inside that shaft I have a 5'x5' vertical shaft. I need to keep the finished thickness of the shaft walls to 4" overall. Thank you.

You would be better off to buy formply, threaded rod and a bunch of 2x4's and form conventionally, use the threaded rod in place of the snap tie, use PVC conduit cut at 4" as the spacer and to make removal of the threaded rod easier, patch the holes after with grout, use the 2x4's for internal wall framing as needed, use the formply for the roof sheathing or sub-floors...waste not want not...except for a bunch of 2' pieces of threaded rod, maybe sell them to some commercial electrician or HVAC guy cheap.

Hello Chris. Thanks for thinking about this. The threaded rod w/ pvc spacers is great idea and probably cheaper than having custom 4" snap ties made if I go wood form route. (I did find a source for 4" snap ties if anyone is interested: meadowburke.com) I will be pretty much repeating the same forming on four floors so the plywood and bracing might also be more cost effective than ICF blocking. I appreciate your responding. Roger

LiteForm makes a knockdown (KD) ICF form with plastic ties that allow the EPS foam to be stripped off. LiteForm KD uses 2" thick high density (2#/cf) EPS foam with a smooth interior and individual plastic ties every 8".

Posted By Rogere on 07 Apr 2015 04:30 PM
Hello Strong Wind Builders and thanks for the response. I had looked at that Nudora single-sided plywood product. Great idea. I need both sides stripped though. If that product allowed for both sides being plywood it might work well. The cross section of a portion of the building is attached and hopefully viewable. The outer/exterior walls are 10" ICF blocks the inner walls are ideally only 4" of poured concrete thickness. In case not viewable, inside the exterior walls, I have a 12'x12' vertical shaft. Inside that shaft I have a 5'x5' vertical shaft. I need to keep the finished thickness of the shaft walls to 4" overall. Thank you.

Why not use the One Sided Nudura product with plywood on both sides? The only restriction I can see is that the Ties that the plywood panel is fastened to are 2-5/8" thick, meaning the smallest thickness of wall is 5.25" (that is assuming you could somehow secure 2 of these ties back-to-back without an insert web, which may/may not be do-able). Your best idea is likely what Chris suggested - using a conventional forming system of some sort.

If no insulation needed, why not just sub it out with conventional aluminum forms? Or perhaps 4" CMU blocks?

However, off topic, I do like the One Sided Nudura to enable the thermal mass on the inside of the home, along with their Plus inserts to bump up the r-value. Seems like a perfect wall for cold climates if you want the thermal mass, and can add the electric chases without too much effort. No Drywall needed either against those bare walls, so just add some interior stucco.

Thank you ICFBdr for contributing on this issue. I will think about the double sided plywood Nudura method but can't sacrifice the additional thickness if it bumps the walls out to 5.25". I am agreeing on the conventional forming being most efficient and probably even more cost effective if the forms can be reused on 4 floors.

Hello sharter. So far the conventional plywood forms with custom ties as per Chris's post look the most promising for the interior walls. Blocks are interesting but beyond my skillset. I like the idea of aluminum forms but have the feeling the cost would not be justifiable. Thank you posting on the one-sided Nudura for exterior walls design. For my building, I would prefer the bare concrete interior faces of the exterior walls. I appreciate your bringing this to my attention very much! I have been planning Fox Blocks and Fox Blocks window bucks but will definitely do some research on your idea.

Another option is to dry stack 4" wide (actual 3-5/8" wide) x 8" tall (actual 7-5/8") x 16" long (actual 15-5/8") cement blocks (CMU), fill the cores with grout, or not, and use surface bonding cement to tie it all together. Another option is to apply spots or beads of polyurethane construction adhesive as you stack the blocks to help hold it all together until you get the surface bonding cement applied.

http://www.quikrete.com/ProductLine...Cement.asp

THank you everyone for their input. This discussion has been very helpful to me as per ICF and forming walls for my project. Looks like conventional plywood forms for inner walls is the way to go. But for exterior walls I back at drawing board. I am still very interested to see what a Fox Blocks or similar double sided ICF wall would look like stripped of foam. I love the sharter idea of exposed concrete faces for inside faces using Nudura One series or IntegraSpec. Problem I see with Nudura is they only come in 6"+2.625 = 8.25" concrete wall thickness. I need 10" thick for my foundation walls. Also by the looks of videos, the exposed concrete faces using either could be a little too crude looking IMHO for my taste in living spaces. I want rough concrete look but ideally fairly uniform in pattern. The Nudura might work if one would lay interior strips on the edges to get an inlaid seams where blocks join but again, the thickness does not meet my building spec. Anyway going back to original conventional ICF blocks, Does anyone have any examples of what a stripped Fox Blocks, etc. form looks like? Thank you.

Rogere, This photo is 1 of 18 thirty-two foot openings using the NUDURA one-sided form. It's currently available on 4",6",8",10",12" and larger cores. Regards

Rogere, NUDURA also offers zero-sided all concrete capability for all of the form sizes from 4" up.

You can order any size web for one sided forms, your 10" is achievable

The exposed face (on the Nudura one-sided) will have 1/2" holes every 8" horizontally, and 9" vertically, they can be left exposed or filled with grout if needed

Stripped blocks, no matter who's look horrible, that is old school, what we did in elevator shafts and stairwells, hence the companies now making a one sided form for us.

INTEGRASPEC is the answer for you, they have had a 4" web for a very long time and they have always been a knock-down ICF wall system, it has only been recently that the other block companies started copying INTEGRSPEC design features, i have used some of the other "block - knockdowns" and they are not nearly as good as Integraspec systems. They even have inserts that enable you to fasten your wood form to one side or BOTH, and they also have an H clip that connects web/ties..it is a very innovative system and it is very accomodating and forgiving system! google it and you'll see

ICF forms one sided have a purpose, for using ICF on one side and exposed concrete on the other for various reasons. Using anyones one sided form in the manner of exposed concrete both sides, no ICF, serves no purpose in using their products. I say this based solely on cost, price out using these neat ICF products for regular forming, concrete exposed both sides and then look at conventional methods as I mentioned previously and you will see what I mean.

Take into consideration the cost of the products, the reusability of them on the project in other areas and your labor.

Thanks Chris. You are right. I am not sure what I was thinking there. Roger. http://www.greenbuildingtalk.com/Forums/tabid/53/aff/4/aft/82126/afv/topic/Default.aspx "Traditional panels vs ICF concrete walls" has a good discussion on the topic.

What Chris said. X2