Insulated Concrete Forms

[GaryM]

looks like the Arxx blocks alright! Did the students enjoy the experience?

One of the two builders we interviewed for our project attended the class that Arxx hosts. He said that he planned to offer the ICFs on any new jobs he did. Said that they were much more flexable than conventional stripable forms.

 

[dmccarty]

Rat,

We thought about using ICFs for our house we are planning.
Heck, I have been looking at ICFs for 10 years. I have spent
alot of time reading up on them and I'm almost 100% sure
when we build we will NOT use ICFs.

One reason is the extra cost.
Another is finding a crew that has experience with ICFs. It
looks simple enough to do and some of the manufactuers have
classes you can go take and actually do the pour. But finding
a building with experience is not easy in my area. I know of
some but not many. The builder we are almost certain to use
has never built an ICF house.

We want an energy efficient house. Getting R values on ICF
are kinda wishy washy. But it seems like the systems we
where looking into had R values of 25 or so. Given that
we want lots of windows, which from an energy efficiency
standpoint are just holes in the wall, it just does not make
sense to me to build a R25 wall in a 12 foot long wall but then
stick a 6 foot long window/hole in the concrete.

Another issue with ICFs is that their use below grade is
supposed to lead to ant and termite problems. The bugs
can't eat the ICF but they can use it to travel to the attic
area of the house....

There are some ICF that have been treated to prevent this
and if termite shields are put into place there should not be
a problem. But I have read that some jurisdictions will not
all the use of ICFs below grade for this reason.

Of course the other benefits of the ICFs, strength and being
quiet still apply....

If money was not tight I would build ICFs. But I think I can
get an energy efficient house using sticks and bricks with the
right details.... At least that is todays plan. /w3tcompact/icons/smile.gif I
reserve the right to change my mind later. /w3tcompact/icons/smile.gif

FYI,
Dan McCarty

 

[TAB]

Yes, the students really liked them. They were way lighter than the forms we have set in the past and all we had to do after the poor was strip the scaffold. It was easier than some of our other pours because we used a pump to place the concrete. We could do that on other pours, but we can usually get the truck close enough and I have plenty of students to wheelbarrow if I can't. We will probably use this system again this spring when we start our next house. This fall we finish the last house we started.

 

[TAB]

Dan, cost is why I didn't use ICF or stress skin panels when we built. I do all the framing and paying for the other systems didn't make sense for my own project. When I build with the students the ICF's don't cost me too much more as we frame in the basement (lower level) and insulate which brings costs pretty much back in line. I have heard the termite stories, but no first hand reports or direct evidence. We don't have much of a termite problem where I am, but if I was more at risk I might look into it much more before I used them.

 

[JATO_RaT]

Interesting finding Dan, never considered the termites, my only experience was with dry wood termites, the kinds with wings that migrate and use your house as a nest and food. They are considered worse then the sub terra type. You treat them by tenting the entire home and fumigating it. We seem to have some ICF buidlers in our area. Out here in CA, you have to get a title 24 energy report which rates in essence, the energy efficiency of your home. Its based on points. You get rewarded for having higher efficiency items like AC's, heater's solar etc. You simply cannot put in all the windows you want here if you can't get the Title 24 report to pass. Windows will count against you. Isn't government great! Heating is far less a factor here then is cooling. I am still considering ICF's, but am very happy to receive any info such as yours to help me decide. I will do it myself as I have done quite a bit of pored in place (snap tie walls) for commercial projects. The insulating factor is perhaps still the most dominate aspect I like about it even though the much improved windows are still the greatest energy loosers. Rat...