Air-Krete
I was wondering if anyone has experience with Air-Krete insulation. I have been researching it and so far have come up with no negatives except the high price.
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In addition to price, there some concerns with post-cure shrinkage, vibration / fragility, and how/when to cover it after it has been installed. See links below for more on these concerns:
https://www.greenbuildingadvisor.com/community/forum/green-building-techniques/18579/unvented-cathedral-ceiling-and-air-krete
https://www.greenbuildingadvisor.com/community/forum/green-building-techniques/18573/airkrete-and-moisture
https://www.greenbuildingadvisor.com/blogs/dept/energy-solutions/foam-place-insulation
Did you limit your research to technical performance issues, or did you also look into what's involved in the manufacturing process and disposal methods after use? If the stuff is really ecologically benign I'd like to hear about it.
I was a prior Air Krete contractor/installer 15 years back. After diving in, buying equipment, advertizing, etc. I was dissappointed that, much though I did not want to believe it, I was finding the product did shrink a few percent. Part of the proceedure was to fill a 5 gallon test bucket, scrap it level, and weigh it. I would keep the buckets and let them dry. It was dissappointing to see the foam inside noticeably shrink after several weeks. The line from the manufactures would likely be there was something wrong with the installer or the equipment. I had brand new equipment. I am a stickler for detail, so I don't by that.
The product of course is crumbly, and I could live with that, given other good non-toxic traits, but combining the crumblyness with the shrinkage to me meant compromized air seal. In my opinion, creating a good air seal is a primary reason one pays the extra money for foam.
I stopped installing it. I couldn't see selling the equipment since I did not believe in it, so I dismantled it. Recently I insulated a new second floor on my home - used Icynene. That is not a commercial plug. I am no longer in any insulation business.
Hi Alan,
I'm in the market for used AirKrete equipment. Do you still have it? I'd buy it from you, even being fully aware of the downsides.
I see it's an old posting, so for what it is worth for the original question poster: I have it installed and dealt with the installation process. BIG problems. For open attic installs it is absolutely useless. As it expands after install. So behind netting in wall cavities it will do fine. It is locked in, to expand into the full enclosed cavity. Even though it is only the netting holding the material in on a wall install. I do not see any shrinking there, really. On a ceiling install it can expand and dry out probably afterward may give some shrinkage. HOWEVER, end result on an attic install is: huge cracks. In another location, also attic install I could measure the shrinkage, as plywood was installed on the trusses for a usable attic space: the shrinkage was substantial. It cannot be installed in one big attic layer apparently. I doubt that 2 layering would prevent all cracks. One big caveat on the problems mentioned above was that the local installer was in conflict with AirKrete, the company, over not using the prescribed mix. Me as the home owner got caught in the middle. NOBODY is now responsible as they both kept pointing fingers at each other. I GREATLY prefer now to work with Rockwool and do it all myself. Forget AirKrete is my recommendation. Or any spray in cellulose or foam. Even having Rockwook installed by a contractor?? I am too picky.
All the best,
Jan
13 years later, letting you know we did this, filling and drilling plaster and lather and brick on the outside.
Went from 146KJ to 110KJ, and we were only able to do 80% of the walls. Major difference felt in cold draft and air coming into the house.