DesignerPages Media
Categories: Surfaces


Icynene is an open-cell polyurethane spray foam insulation. Installed on-site, it can be used to insulate basement walls, above-grade walls, attics, floor cavities, and interior partitions for sound attenuation. Icynene can significantly improve the energy efficiency of a home as well as improve the home’s moisture management, leading to greater durability.

Icynene, open-cell polyurethane spray foam insulation. Wall cavity application.

There are several factors that contribute to Icynene’s energy efficiency. As Icynene is sprayed, it expands to 100 times its volume almost instantly. As it does so, it completely fills and seals the entire wall, floor, and roof cavities, which creates a complete air barrier. The creation of an air barrier via insulation is particularly useful, as both interior and exterior air barriers are difficult to construct and maintain. This 'fool-proof' air barrier greatly reduces the amount of unwanted air infiltration, which typically makes up a significant percentage of a home’s heating and cooling requirement.

When Icynene is used to insulate an attic, it is typically sprayed between the roof rafters, as opposed to between the ceiling joists. Installing the insulation at the roof line keeps the attic within the conditioned space. This is very important if HVAC equipment and ductwork is contained in the attic. A vented (i.e. unconditioned) attic is at outdoor temperature in the winter and can rise above 120°F in the summer. As such, even if the ductwork and equipment are insulated, there will be significant energy loss from these components in an unconditioned attic. Using Icynene to enclose the attic within the conditioned space eliminates these energy losses, which greatly improves the efficiency of the system and leads to smaller heating and cooling loads.


Cathedral attic application.

The vast majority of moisture that migrates through a wall travels on air currents. Since Icynene significantly reduces the airflow through a wall, it also reduces that moisture that can enter the wall. As such the chance of moisture accumulation, mold growth, and ultimately structure rot is substantially reduced.

The one main drawback to Icynene is cost. On average, the installed cost is about 2-3 times more than fiberglass batt. We’ve found that the payback is typically 6-10 years, based on energy modeling that we’ve done. This payback, along with the improved durability and performance, is often acceptable to our custom design clients while the extra cost is sometimes a deterrent to production builders.
Posted March 25th, 2008 by Stephanie Horowtiz


  • Rich Brown says:

    This article shows an excellent understanding of Icynene. A couple of corrections/additions: Icynene is Isocyanate based instead of Polyurethane… the difference being that polyurethane is solvent based, polyicynene is water based. The only reason this matters is off-gassing. Solvent-based polyurethane foams give off volatile organic compounds for months or even years. Icynene is fit for habitation after 24 hours.

    An additional benefit to the unvented attic assembly is that the ridge vents, soffit vents and gable vents are eliminated… eliminating the risk of wind driven rain infiltrating the structure via those openings.

    Living in the Southeast, I am used to 165 degree attic temps in the summer, and used to seeing the life of attic HVAC units cut in half compared to basement or crawl units. The long-term savings of getting your attic temperature under control begins to mount at that point.

    Finally, on your estimate of payback time, one angle to look at is the monthly cost of additional mortgage you’d pay for Icynene vs. energy savings. Icynene calls it “The 30-day Payback.”

  • Joel Crowson says:

    Can this closed, non-vented attic system be used if you have an attic a/c unit with gas heat? Seems like gas fumes, carbon monoxide, would be trapped and filter into the living area of the house.

  • icynene says:

    […] insulation. Installed on-site, it can be used to insulate basement walls, above-grade walls, … makes it green? - Indianapolis StarInsulation: icynene foam (below) seals the home tight, […]

  • Gregg Turner says:

    I have a 90 year old house and am considering using Icynene to insulate both the wall cavities and attic. The walls are plaster and I am replacing the exterior siding with hardi-plank. This will allow access to the wall cavities through the exterior sheathing when the old siding is removed. Is the Icynene a good fix and do you have any additional tips? The attic currently has blown insulation in the floor joist. The attic is extremely hot in the summer and cold in the winter. An HVAC unit and ductwork is in this space. Do you recommend Icynene? Do I need to remove the existing blown insulation? Do I shut off existing attic ventilation? Thanks

  • Rich Brown says:

    I’m sorry that I haven’t checked these pages recently, and hope that my comments are not completly useless for their lateness.

    Joel: The International Code Commission’s requirements for the “Conditioned Attic Assembly” (Section 804.6) require that combustion air be provided to any HVAC or Hot water units. Of course, if fresh air is piped directly in to the combustion chamber, then the normal exhaust on every unit gets rid of the CO or CO2.

    The second comment/question above is a little ambiguous, but effectively, what makes Icynne green is the long-term savings of resources expended to keep a house warm or cool. What makes it green is the long term savings on trying to keep the humidity correct, and what makes it green is the lack of atmospherically damaging refridgerants that closed cell foams release over the life of the product.

    Finally, Gregg’s questions: Icynene is a great choice for retrofitting older homes. Do the existing walls have any insulation or are they empty. If they are insulated, you might want to try insulating under the floors and in the attic first. By stopping the vertical movement of air, you may get the permormance you need out of the existing walls. If there is no insulation in the walls, there is a “slow rise” version of Icynene which can fill those wall cavities and insinuate into every crevice. One caviate… Icynene cannot be used with old “knob and tube” type wiring.

    Rich Brown
    Team Leader
    Foam Worx Insulators

  • Caldwell says:

    Disappointed with my recent installation of icynene. All literature and sales pitch from the company is that it is totally inocuous in terms of fumes and off-gassing after 24 hours. I had it installed in the attic, and one of my son’s bedrooms has the door that leads up there, which is also used as my home office. He hasn’t been able to sleep in his room for three weeks due to the fumes. Luckily, heating season is coming to an end here in the northeast, and we have been able to open the windows most days. The installer denies that anyone has ever complained. At this point, I am wondering if, once I reinstall wallboard in the attic, if we are going to be smelling it forever, and if so, ,if I am going to have to rip it out in a year. There needs to be more testing on these new products - and not on the consumer who finally brings a lawsuit.

  • Rich Brown says:


    I am sorry to hear about your disappointment with the smell of the installed Icynene. Although the environmental engineer’s reports from the University of Sascatewan and others certify a building for safe habitation 24 hours after spraying, it doesn’t mean that it is completely odor-free. It has a strong latex paint-like smell, that does need a good airing out to diminish. If that attic has been closed up since spraying, it will take extra airing out to get the smell out of the wood in the attic and such.

    I’ll be shocked if you need to remove it to get the smell out… like I said, just get some air moving up there. The open cell structure of the Icynene may be trapping some of that smell as well, and since it is an insulation, it will take a couple of days to replace the trapped air in the millions of open cells.

    Although I am a contractor and certified sprayer, I am one of the approximately 5% of the population that is allergic to the active foam. If I’m in a building that is being sprayed and my mask slips, I get seasonal allergy symptoms for a couple of days. However, I go into buildings that have been sprayed one to two days ago every day without ill effect.

  • jmichau says:

    I have an older home and just had the whole roof rebuilt, we used 2x8 for the roof raffters. It seems that we will be using the space (approx 1000sq) for a master suite in the future. There is a 11/12 pitch. I would like to use your product in a few years prior to applying the walboard. The decking used was techshild, as you know it has foil on the underside. I realize that it would no longer be doing its job, but do you see any issues with installing the foam on to it. I would guess that this would give me a totally seald roof system. I would love to here from an installer in my area.
    Central Arkansas

  • A McDonald says:

    I too am having the same problem as Caldwell with the smell in my house. I have a new house under construction and was convinced to use Icynene because of it’s lack of smell and off gas. My sinuses ruptured on an aircraft back in the 60’s and I have had problems continually since.Because of this problem, I had Icynene sprayed through out the house six days ago and have not been able to work in it since. The fumes are so strong that they make my chest hurt within ten minutes of going inside. I think I have made a grave mistake by using this product. I think the fumes are even going to be stronger when warm weather comes. I really don’t know what to do.

  • Rich Brown says:

    Wow, I need to check this site more often. Caldwell and A McDonald. I wanted to check in and make sure that things have cleared up on your houses. I’m hoping that you took my advice and put some fans in place to move a volume of air past the spray foam. I also want to be sure that you did in fact get the Icynene brand, not one of the 20 other brands of open cell foam which can sometimes be sprayed by unscrupulous contractors who call it Icynene. When this type of contractor is caught, they claim ignorance by saying, “Icynene’s just the generic name for all open cell foam… like Kleenex.” I would encourage you to go to and click on the world map in the bottom left corner. Keep clicking on the U.S. until you get the contractor finder, type in your zip code, change the miles to 150 and see if your contractor pops up. If not, it’s very likely that you did not get Icynene.

    There is a reason why the Icynene brand is the one chosen by the American Lung Association for their Health House projects.

    Jmichau, I hope that you got your questions answered, and your insulation installed. For other readers, Icynene has been tested and it is documented that it is acceptable to spray directly to LP Techshield. You are right, the Techsheild no longer does anything except continue to function as OSB.

  • junimooni says:

    Mr. Rich Brown,

    I am the sister of A McDonald. No, his problems with Icycene have not cleared up. It looks like he has developed a permanent sensitivity because of this installation which was supposed to be “fume free” after 24 hours. Yes, he used the brand Icynene and it was installed by a licensed contractor from their site. However, my brother cannot get either the installer or the company to recognize the problem. He has basically a partially built new home that he has sunk his life savings into and he cannot even go into it!
    Someone in the industry and in our Government agencies responsible for environmental safety and consumer safety should start holding these companies liable for their products.

  • junimooni says:

    yes, my brother has put fans in and aired out the house daily…my brother goes in and opens it up. it is looking like he his permanent lung damage because of the Icynene installation.

  • junimooni says:

    My other brother has to go in and open the house. I am so enraged by these doubtful negative comments that I can’t even type correctly.

  • Brian N says:

    Yesterday we had one of the official Icynene contractors found in the official website install Icynene insulation in our older home. There was no “24-hour” advisory provided by the company or the installer. When I asked the installer after the job was finished how long it took for the smell to die down, he said “a few minutes”.
    We had the windows open with fans going all night last night and when I arrived home from work today the noxious odor was overwhelming. It is nauseating and is causing headaches well past the 24-hour period with no signs of letting up. Our attic where the insulation was installed has only two very small hatches for access, one in each upstairs bedroom. This weekend I will find a fan small enough to fit into them and try to vent it out the best I can.
    My worry, especially after reading the problems others have had with long-term odors, is that this is a problem that won’t go away any time soon, if ever. I can barely stand to be in the house for any length of time without fighting headaches and feeling sick to my stomach, much less sleep in the bedroom right under the attic where it’s installed.
    What a HUGE mistake we made having Icynene installed!

    • Rick says:

      I had Icynene open cell foam installed in my attic, closed cell Icynene installed in area’s in my basement crawl spaces and JM Corbond III closed cell foam installed in my bedroom and basement walls. What a huge mistake!  My contractor was recommended by both manufacturer’s as an “approved contractor”. Neither company will tell you what chemical’s you have been exposed to when it’s applied wrong. They hide behind their rules and say screw you homeowner, if it’s not applied correctly. Read Icynene’s MSDS and compare it to other manufacturer’s. Icynene hides the true chemical’s but does disclose MDI which is hazardous to your lung’s. Contractor’s in most cases do not tell the homeowner’s what to prepare themselves for.  In my case,  both products were not mixed properly by the contractor which may be the real issue here and possibly yours. However, Icynene’s sales representative stated there was nothing wrong with the product applied in my home. Another lie told to me. 4 month’s after the products removal, area’s of my home still smell like the chemical’s. Icynene says they are amine. Safe. Use extreme caution with all foam products and the contractors who apply them. They do contain chemical’s known to cause irreversible lung damage when you are exposed to the uncured resins. I see class action lawsuits coming in the near future for all manufacturer’s in this “Green Business” field due to incompetent certified applicators and disclosure problems within the industry. Some manufacturer’s are just as guilty as the contractor’s for withholding what the true risks are to homeowners and installer’s. Do not rely on their finished products MSDS when it is “known” the products are “not applied correctly”, as in my case. I only learned the truth because I refused to lay down and go away. I dug deep to find some of the truth. 14 month’s after application and 4 month’s after partial removal, I am still fighting them all. Understand this if anything, “Contractor insurance” does “Not” cover workmanship error. The same applies to your homeowners policy. When there is a product failure the manufacturer does not help you! These products are classified as “contamination”, “gas” and “workmanship error” when a failure or odor occur’s. I know first hand! You are on your own!This chemical insulation business is so profitable that a few lives apparently are worth the risk to them all.  

  • taylor says:

    Just to add perspective. I also had a horrible experience with icynene. Had it installed in my basement ceiling mostly for sound-proofing. Was told it would smell for 3 hours but will air out quickly. A day later we moved out of the house. After 8 days I had the installer remove all of it. Took them a week and even after most (can’t feasibly remove all of it) was removed, it still smelled for a week. The smell is finally gone now that I have the fiberglass R30 batts (which I think are actually better sound proofing) and the drywall up.
    Horrible experience. I don’t know if our situation was an anomaly or not, but I would never use that product (or any spray foam insulation) again!

  • John moy says:

    Who has experience blowing Icynene or similar into closed wall cavities? I’m considering whether the best way to insulate a 100-year old shingle victorian with excellent walls is by filling the wall cavities with a foam.
    Any thoughts?

    • Info says:

       Hi John for this you would need to use the pour formula. This work great and as it rises slower it finds its way in to all the gaps. Have a look on for a installer local to you. Were based in the UK and have recently done a few houses with this. Excellent product.

  • swain says:

    I don’t know what my problem is. I had Icynene sprayed in a new construction home. Said power bills would be extremely lower than with any other insulation. However, my bills seem to be much higher. Plus in summer time, it will stay cool. Today the outside temps were near 100 degrees. The inside temp rose 8 degrees higher than what it was supposed to be. I installed a two stage 16 seer heat pump. Do you have any suggestions? Could the icynene not be thick enough? Any thoughts?

    • Kevin says:

      I have been spraying Icynene for 4 years great product and the air sealing is great but r value in your application compared to fibreglass out performs fibreglass and cellulousse. I install all three and sometimes people just dont put enough of it in. Where people put in r 20 fibreglass they try to do r 10 Icynene that would give you the same performance and the same cost. Doing an r 20 icynene vrs an r 20 of traditional products will definately work better. The installer has a lot to do with it as a great installer can make fibreglass work much better than a poor installer. If it is two people who are doing a great job the foam Icynene or other is the way to go!!!

  • Ed the engineer says:

    Hi all,
    I had icynene installed by a contractor from the official website. I too was not informed that it would still off-gas for awhile. I went up with a vacumn cleaner that night to do the fine cleanup. After an hour, a had a headache. Later the next day, my wife called to say the photoelectric smoke detector that we had removed during installation and put downstairs in our bedroom, had gone off after being reinstalled that morning. So it did’nt like something in the air I guess. My son went up and opened up the skylights, because we had closed them that night because of possible rain. Shortly after opening them(1 hr) the alarm stopped. I went up 36 hrs after spraying stopped to do more cleanup and I started to get a headache again. Couldn’t open the windows because of possible rain again. Opened them this morning. After reading more on offgassing, I’m a little disappointed that the doc. states no VOCs and see figure 1 which has a table showing detectable chemicals up until 30 days. Seems like a total contradiction. Luckily its supposed to heat up to the 80’s today so maybe my attic will get baked and the smell will come out sooner. I will delay the blueboarding till its out.

  • Ed the engineer says:

    UPDATE: Its been about 2 weeks and the smell is almost gone. This seems to be inline with the OCETA document on Icynene. I have yet to put back the smoke detector, but will probably try after the 3 week time to see if it detects anything. See the link to this table.
    If all goes according to the table, we should have no odor between 3-4 weeks. I’ll report back. Other than that it seems to perform as advertised. We had a hot day in the mid 80’s where the attic would have been in the mid 90’s to low 100, but it stayed at 85, the initial temp before I closed the windows.

  • Klothman says:

    Everyone, try spraying aluminum paint on the cured isynene; it is used successfully to spray onto burned wood to stop the fire smell in burned houses.

  • Thanks for sharing this nice suggestion of insulating the walls. Dry basement walls can cause electric short-circuit . So its better to insulate the basement walls to save from this problem.

  • Ant1780 says:

    I had Icynene installed 3 years ago and I love everything but the smell. I own a small cape and had the Icynene installed right to the roof decking. I have three doors that provide access to the crawl space behind the knee walls.

    The Good:
    Heating bills dropped 30% and I’ve saved the utility bills to prove it. I have two floors on one zone and as long as I keep the furnace fan set to “on” and not “auto” I can keep both floors within 2-3 degrees of each other. This has. Been a Godsent because I have neighbors with the same style house whose kids can’t sleep in the second floor rooms during a heat wave.

    The Bad:
    The idea of the smell going away after 24 hours or even a week is a line of crap. Three years later and the smell is still there! It’s not there all the time but the hotter it is outside, the worse the smell is inside.

  • Richard Beyer says:

    I too had a very bad experience with Icycene. 2-1/2 years later the product still smells, even after the open cell product was removed. I would love to hear from every homeowner who has had trouble with their Icynene products, open and closed cell. I had both installed in my home. A major regret. Richard Beyer 860-460-5434

Promo Video


Latest from Otto

h2o architectes Complete A Parisian Apartment Full Of Sloping Lines

French firm h2o architectes have revamped an old s...

Hospitality Construction Services Design Pepita Restaurant in Ballston

Constructed by Rob Mescolotto and his Washington D...

GrizForm Design Architects Reveal New Farmhouse-Inspired Restaurant In Virginia

Award-winning firm GrizForm Design Architects were...

IIDA 2016 Library Interior Design Awards

The IIDA and the American Library Association (ALA...

Inside ImpactFlow’s New Office in Portland’s Evolving Eastside

Portland-based interior design firm Weedman Design...


Do you have a product you would like to share with us? Submit to 3rings.