For those of you who do not know what “Rastra” is….it is an “ICF”.
For those of you who do not know what an “ICF” is…it is an “Insulated Concrete Form”.
Basically, a form made out of Styrofoam that allows concrete to be poured into it forming walls for a house. Pretty simple concept that seems to work pretty well. I am told there are in excess of 70 types of “ICFs”.
From what I have seen so far, not much difference in most of them except for “Rastra”.
“Rastra” is manufactured as a “block”. Some of the others are as well but “Rastra” is unique in a few ways.
First, it is much heavier than the majority of the other “ICFs”. Maybe it is heavier than any of them. I don’t know. This would be pointed out to be a disadvantage if you speak with other ICF professionals. It comes in 90″ sections or blocks. About 150 lbs each. From an installation standpoint….it is more challenging to stack. Or at least, it requires a different approach to installation.
The second thing about “Rastra” is that it does not require near the bracing the other ICFs do. I can stack walls for the first floor using 12 inch “Rastra” and brace only the corners if I do not have large window openings to brace. Pretty impressive.
Another thing I like about Rastra is the ability to directly apply stucco to it using a “2 coat process” as opposed to the normal 3 coat requirement. No “wire mesh” is required either. Pretty big advantage if stucco is the way you are finishing the exterior. With the excpetion of “Perform Wall” I do not think any other ICF can do this.
“Rastra” is also “Environmentally friendly” using 85% recycled Styrofoam in the manufacturing process. Another good reason for using it.
As to the other advantages of ICFs, “Rastra” meets or exceeds all of them. ICFs are just a better way to build in my opinion.
So, that is my pitch for “Rastra”. If you want more info, go to the web site.
Now let’s talk ICFs in general. I’ll try not to let my “Bias for “Rastra” interfere with my evaluations.
Why aren’t’ more ICFs being built? I am told they are on the rise but some argue they are “cost prohibitive”.
In the same breathe, they say the cost overall is only about 10% to 15% higher than “stick built” homes.
OK
If 10% to 15% is accurate, I would argue it would be a “no brainier” not to build an ICF. A small price to pay for a far superior product that likely will appraise considerably higher than it’s “stick built” counterpart.
Let me tell you what I know about ICFs vs Stick Built homes and you decide:
Life expectancy on a stick built is at 80 to 85 years…ICFs go 200 years plus.
Typically, insulation with a stick built is R-19. ICFs use expanded Polystyrene (Styrofoam). Rastra claims in the R-30s minimum with the 12 inch block.
Heating/Cooling costs on the study I saw were $820 a year for stick built and $240 a year for the ICFs (on a 1500 foot home). 3x better.
Sound insulating qualities for the stick built were STC 32…ICFs are at STC 48. Again, this according to the study I saw. I have “first hand” experience with this. I build with “Rastra” and can tell you if I am trying to yell at my guys and they are on the other side of the wall…they have a hard time hearing. Or it is they just don’t want to hear?
Then you talk about environmental friendliness…. stick built poor, ICF excellent. Easy to reason using common sense. I do not need a “study” to know this.
So there you have it.
One mans opinion and one evaluation from the Canadian Portland Cement Association. Take it for what it’s worth.
From my perspective, there is no comparison when talking about ICF vs Stick Built. ICF wins hands down.
Any of them are good, but for me, “Rastra” is the best.
I am going to build with “Rastra”, Incorporate “Smart technology” into the house and use what is practical in terms of “Environmental” products.
I will be “competitive” with any stick built with similar footage. The house will be “Green” and pretty “Smart”.
