[podcast]http://www.green-talk.com/podcasts/aircrete.mp3[/podcast]
Note: post has been updated as of 2/15/2010 due to conversation with Keene Christopher, CEO of AirKrete.
The other day as I was sitting around of table of women at a Super Bowl Party, one of the women commented on how cold this particular winter has been Quickly the conversation turned to how cold their own houses were and the cost of their utility bills. Some were wearing bulky clothing and keeping their homes quite chilly to keep their bills in check. So, I wondered, have you seen your own energy bill soar in the last couple of years?
As many of my loyal Green Talk readers know, I have written extensively about how to button up those air leaks in your house especially in your attic. But sometimes, simply caulking is not enough when you don’t have adequate insulation in your attic, crawlspace or walls.
I am fascinated about different types of insulation, and have been particularly interested about AirKrete, for sometime. This product has been around for over 25 years.
During a recent green exhibition, I interviewed New Jersey AirKrete installer, Fabio Alberti of Alberti Insulation, about the attributes of the product. I urge you to listen to the above short podcast. It is really quite informative.
What is AirKrete? According to Alberti, it is a cementitious foam insulation comprised of Portland cement high quality magnesium oxide (MgO) cement, ceramic talc, water, and a foaming agent. The Company states that the product is fire proof and mold resistant, and free of formaldehyde, CFCs, asbestos, and all other carcinogenic fibers. It does not off-gas.
In addition, it has an R factor of 3.9 per inch and completely fills all the nooks and crannies within a wall cavity. It does not expand within the cavity like foam, so there is no worry that it will blow out the wall. (See the Material Data Safety Sheet here as well as independent tests and approvals authenticating the Company’s claims.)
According to Alberti, the main difference between ordinary foam and Airkrete is that AirKrete is 100% fireproof rather than containing a flame retardant ingredient. In the event of a fire, AirKrete foam will not burn or create smoke.
As to cost, Kristopher stated a board foot (12″ by 12″ by 1″) on average costs the same as 1/2 lb polyurethane foam. New Jersey based Alberti states that a typical AirKrete installation would cost 20% more than the installation of foam, but would be 40-50% more effective than foam (depending on the installation) since it does not shrink from its original installed state. He claims foam, on the other hand, shrinks.
How is the product installed? Watch the above video. The product fills the walls like other foam applications and cures within a few days. It is ideal for new construction and can be added to existing homes. The beauty of the product, according to Alberti, is left over product could easily be disposed of in your garden.
During my conversation with Alberti, I was impressed that AirKrete could be installed through an exterior wall so less damage would be done to the interior walls of your home. He explained it is the only insulation that can be installed from the exterior as well as through brick veneer.
So, is it really fire proof? The above video shows a penny being burned on top of AirKrete. The foam does not burn. The Penny…well, it did not do as well.
The Company does not maintain a list of installers on their website. If you are interested in AirKrete, simply contact the Company through their email address and they will furnish you with the name of a local installer.
A couple of caveats about the product. While I was writing this article, I thought all types of cement are the same. Creating Portland cement is a heavily embodied energy process. According to the Material Resource Institute at Penn State,
“Concrete is, by volume, the most common manmade material in the world, with 2 ½ billion tons poured each year. In the process of making Portland cement, a main component of concrete, one ton of CO2 is released into the atmosphere for each ton of cement produced, accounting for 7 percent of manmade global emissions.” [Source]
However, what makes AirKrete different is that it is made out of Magnesium Oxide not Portland Cement. According to George Swanson, in his article, ” Magnesium Oxide, Magnesium Chloride, and Phosphate-based Cements,”
“Depending upon where they are mined, magnesium oxide and magnesium oxide/magnesium chloride cements require only 20%-40% of the energy required to produce Portland cement.”
Swanson’s article is a must read, comprehensive look at the use of Portland Cement versus magnesium oxide and magnesium chloride cement. Most notably, he explained the health benefits of using magnesium oxide and magnesium chloride cement to Portland Cement.
Inevitably, with greener products, you have to pick your poison. Foam insulation, on the other hand, contains polyurethane, a petroleum based product, which environmentalists have argued depletes a dwindling natural resource.
One caveat about the product. Alex Wilson, founder and executive editor of BuildingGreen, LLC in Brattleboro, Vermont, who I admire very much, wrote in his September, 2009 article entitled “Foam-In-Place Insulation,” that there were few trained installers and it may be more expensive to hire one that was far away from your area. In my situation, Alberti covers New Jersey, and he is reasonably close to me. Like Alex stated, installing AirKrete may not be so easy for you in your area. Christopher confirmed this issue but stated more and more installers are coming aboard.
In addition, Wilson states,
“Other than availability, the biggest problem with Air Krete is that the cured foam is fairly fragile; if exposed to frequent vibration, such as along a busy highway, the foam can begin to disintegrate, reducing its performance. The manufacturer is working to solve this problem.”
Christopher denied this statement and had no idea where Wilson heard this problem. Keep Alex’s point in mind if your home is exposed to frequent vibrations. Contact the Company to see if they have resolved this situation.
Readers, has anyone used AirKrete ?
Have you found this winter to be worse than prior years? Or are we just getting older and starting to feel the cold?
Similar Posts:
- 10 Green Insulations to Reduce Energy, Increase Comfort
- Icynene® Insulation–The Ultimate Barrier to High Energy Bills
- Recycled Denim Insulation by Bonded Logic: Green, Warm, and Itch-Free
- BASF’s COMFORT FOAM® Reduces Energy bills and Increases Comfort
- Wool Insulation by Oregon Shepard: Natural, Energy Efficient, NonToxic
Tom Spoler says
Air Krete is not made with Portland Cement but with a Magnesium Oxide (MgO) based Cement. It does not require the same amount of CO2. Go to http://www.greenhomebuilding.c.....ENERAL.pdf
Green Talk says
Tom, you are absolutely correct. I spoke with Keene Christopher of AirKrete Friday about what was in the product. You beat me to the punch in correcting my article. I had called him trying to find out AirKrete’s position about cement’s high embodied energy. We had a wonderful conversation and he clarified what I was told in my podcast. Thanks for weighing in.
Tom, how do you know so much about AirKrete? Anna
UPVC Windows says
This appears to be a very useful product! Is this similar to the Selley’s spray on insulating filler? AirKrete! I will keep this in mind when in my hardware store. There are so many foam products on the market yet little is spoken of its Eco qualities. I will reserve my professional decision on its real value until I have researched more thoroughly. Looks good though!
Chris says
Anna – question for you. I recently had air-krete installed in my new home which is under construction. Construction on the outside included OSB sheathing, rigid foam insulation, and a housewrap. I am confident drying from the inside to the outside is minimal if non-existant.
On the inside wall airkrete was sprayed in. A housewrap was put over the drywall side of the studs to keep the air-krete from falling out during installation. In accordance with standard AIr-Krete installation, the inside house wrap was slit 4-inches horizontally approximately ever 12-inches vertically. This was to help the air-krete dry.
According to Air-Krete the drying time should be 2 days. A week went by before my drywall started installing sheetrock on the walls. He did not notice any moisture. However, and approximately two weeks after the Air-Krete was installed, we found a stud needed to be installed on a wall to support a shower door. The housewrap was slit at that location, and the Air-Krete removed.
The Air-Krete was moist, like moist sand. It did not “drip,” but stuck together due to the moisture content. My drywall contractor was very concerned the moisture will damage the drywall, especially future installation of mud and tape. I contacted AIr-Krete headquarters and they have suggested installing a dehumidifier and heaters and stopping the drywall installation for at least a few days to let the Air-Krete dry.
I guess my question is, does this seem normal? Could I purchase a moisture meter with a probe and stick it through the installed drywall into the Air-Krete to see if it is dry, so I can verify the mud and tape can be installed since the Air-Krete is dry? And where do I get such a probe? I have seen meters for checking the moisture content of wood and drywall online, but they have short prongs. I know this may sound silly, but would a soil probe which measures moisture work?
Any help or guidance on what I should do next will be appreciated?
Anna@Green Talk says
Chris, I sent your email to the CEO of AirKrete. I spoke with Keene Christopher, CEO of AirKrete. He advised me that 2 day cure period is incorrect. Cure time is affected by humidity, temperature, and cavity conditions. In the best of conditions, it would take about one week to cure. However, he indicated that you could put the drywall up after an insulation inspection since it will continue to cure.
In your circumstance, it seems like you are over-insulating the house, so your cure time will take longer. Christopher is going to respond to both you and me so that I can post it on the website. If you still have questions, after he responds, please continue to copy me in your emails so I can post it on the website for others. I am not an expert on AirKrete so I enjoy reading the questions and responses. It is a learning experience for both my readers and myself. Anna
Anna@Green Talk says
Chris, I received a return email today from the CEO of Airkrete. He wants to know your date of install and location. Can you provide this information in this thread? Anna
Dennis says
I assume that this could be used to fill the gap between an i/c rated recessed light fixture and the drywall? Could it also be used around the recessed bathroom heat lamp fixture?
Jim says
Ha I love that demo video! Yeah this is pretty cool stuff. The only issue is that it’s definitely more permanent than the spray-in type or hang-up fiberglass insulation, but it’s so much safer, it just might be worth it.
Robert Wolfe says
Whatever was the outcome of the moisture possibly damaging the wood studs and drywall. I’m considering having this installed in my existing home and wonder if this can rot the wood studs while it is curing?
Also is this recommended for an attic floor where normal fiberglass insulation is used. If so I assume you would remove the existing insulation and then spray this in place?
Anna@Green Talk says
Robert, I contacted AirKrete and asked him to respond to the commenter. I never heard back from either. Before you install, I would call AirKrete. The president is really nice and he will talk to you. Anna
Rita says
Hi there, just learned about Airkrete, wondering if you could recomend any contractors in the Toronto area, i’ve had an estimate from Brand already but would like to get more before i make a decision. I watched the video where they used airkrete between joises using a nylon mesh to hold the foam in place, very impressed. I would also like to know if it can be done in colder tempetures. There’s an 1″ gap between the drywall & cement blocks where the application is needed.
I appriciate any help.
Anna@Green Talk says
Hi Rita, you have to call Airkrete to find out who their distributors are. I would ask to speak to Christopher Keene, the CEO. He is incredibly accessible.
As for the one inch gap, is this an older home? You won’t get a lot of R value with a one inch gap. I would recommend you look at closed cell but most closed cell is for open cavity.
As for cold environments, my understanding is it is fine. Mr. Keene’s office is based in Syracuse. NY. Let us know what you find out. Anna
Rita says
Thank you Anna.
David says
I brought Airkrete in from 2 states away to install in a customers house after the plastic(tripolymere) rep completely pissed off the owner of a million dollar historic house. My customers heating bill went from 1900/mo to 800/mo. A little moisture will not do anything to the studs, it takes years of moisture to rot wood.
Anna@GreenTalk says
David, that is amazing. Did they spray it in through the walls or did you go down to the studs?
Ed says
One thing to be aware of: Part of the AirKrete product, (I guess the foaming agent), has a short shelf life. If an insulating job is done with expired product the foam will collapse and will end up as a layer of fire brick at the bottom of your empty wall cavities!
Maybe this would only happen with an inexperienced installer? I do not know.
Anna@Green Talk says
Ed, what is the shelf life? That’s seems scary. How do you know this? Anna
Richard says
I looked into AirKrete extensively while considering insulating my walls, attic and cold-floor with AirKrete, but I live in Houston where our houses are always swaying and moving with the soil and I simply could not find enough evidence showing that AirKrete would not end up crumbling to the bottom of the wall cavity after years of soil movement and hurricane wind sway. I would love to have some proof that AirKrete would last in such an environment . Hopefully one day there will be some good long-term data based on actual home installations in the Houston or Galveston area that show that AirKrete holds up to the vibrations and movement.
Graham Dewar says
Hi Anna,
For all your Canadian readers we are the Canadian national distributor for AirKrete Inc. Our website is as posted above.
Thank you,
Graham Dewar
airKrete Canada Inc.
Anna@Green Talk says
Graham,
Quick question for you. Someone told me that the MagOxide can eat plumbing pipes. Have you ever heard about this? Anna
Ana in Toronto says
Anna, there are apparently several discrepancies that I found on the website in Canada. I just had Brand Insulation come and give me a quote. I’m expecting someone from Foam Comfort to come by shortly to give me a second quote. At this point, I’m not sure that I will proceed with either.
http://www.airkretecanada.com/installer-find.html
Installation FAQ:
THREE SETS OF HOLES are drilled into the interior walls, of every room in the house, BETWEEN EACH SET OF STUDS.
Depending on your home’s layout and construction, holes may also be drilled from the outside. THE HOLES CANNOT BE DRILLED THROUGH STUCCO, ONLY THE MORTAR BETWEEN BRICKS.
OUTSIDE HOLES ARE DRILLED SPACED 3 BRICKS WIDE & 5 BRICKS HIGH. If the spacing between Bricks is narrow, then the drill WILL CHIP your bricks.
AirKrete insulation is mixed in drums outside the home.
The insulation is then pumped through hoses into the house and “foamed” into each drilled hole using low-pressure air.
When completed, interior holes are patched with drywall compound and exterior walls are patched with mortar. YOU WILL HAVE TO HAVE YOUR INTERIOR ROOMS REPAINTED. IF USING LIMESTONE MORTAR OUTSIDE, MUST BE SEVERAL DEGREES ABOVE FREEZING IN ORDER FOR MORTAR TO SET and begin curing.
In new construction, airKrete is installed at the same time as the vapour barrier (a requirement under national and provincial building codes). A special mesh is used over the studs to hold the foamed-in insulation in place. Once airKrete dries (usually in 24 hours), drywall can be installed normally over the studs. During installation, airKrete has the consistency of shaving cream when “foamed into” the walls of houses and buildings at low pressure. Within 24 hours, it dries completely and will not expand, contract or settle over time. CONTRARY TO THE WEEK THAT YOU WERE TOLD…
Is Air Krete corrosive to metals?
No. After airKrete curea 24 hours after installation, it is dry and completely inert.
Does airKrete break down, sag or shrink over time?
No. After it is installed and cured it is completely inert. CRUMBLING DUE TO MOVEMENT?
Anna@Green Talk says
Ana, I wasn’t sure where you saw the discrepancies so I can show the CEO to answer your questions. Is it where you have the information in caps? Can you list them for me. Did you call the company in NY? i would be curious what the CEO says. Anna
Mark says
Anna,
One discrepancy came from your own column:
“Anna@Green Talk October 18, 2010 at 10:41 am
Chris, I sent your email to the CEO of AirKrete. I spoke with Keene Christopher, CEO of AirKrete. He advised me that 2 day cure period is incorrect. Cure time is affected by humidity, temperature, and cavity conditions. In the best of conditions, it would take about one week to cure. ”
Keene Christopher, CEO of AirKrete says ONE WEEK in the best of conditions, but the AirKrete Canada installer says:
“Within 24 hours, it dries completely and will not expand, contract or settle over time. CONTRARY TO THE WEEK THAT YOU WERE TOLD…”
This directly contradicts the CEO himself!
Anna@Green Talk says
Mark, I would go with the CEO of Airkrete. What is the is status now with the project? Anna
Solar Thermodynamics says
This product is excellent i wonder how long until it is signed off for use within the UK. Really good for a personal project though if you can do the mix by hand and without and large rig.
Jonathan says
any news on a UK supplier of this or and BBA testing occurring. I have an excellent project i would love to try this out on.