jump to example.com

Two part foam spray-in insulation is becoming the standard in new home construction. It installs quickly, it boasts a high R-value per inch, and it prevents energy-stealing air leaks. Until fairly recently only pros could do this job, but lately companies like Dow Chemical have released products like the Froth-Pak 12 — it’s the same foam the pros use, but scaled down for smaller Jobs like fixing those pesky air leaks.

Froth-Pak’s two part chemical reaction creates a fast-expanding, quick-curing polyurethane foam that you can spray anywhere. Unlike Dow’s other foam product “Great Stuff,” you can spray Froth-Pak through a variety of nozzles. A wide fan nozzle broadcasts the material to cover more area per pass, while a “pour” nozzle helps to fill in larger gaps.


The Froth-Pak 12 kit runs about $35 and covers 12 board feet (.03m³). Dow also makes larger kits for the more ambitious among you.

Froth-Pak [Dow]
Froth-Pak Kit Street Prices [Google Products]


25 Responses to Froth-Pak 12 Foam Thrower

  1. Nice this could come in handy for insulating my 19th century Victorian.

  2. David P says:

    Hmm, they give the coverage in board-feet…is that the final expanded volume?

    That seems like a sneaky way of saying “1 cubic foot” to make it sound bigger. Is this really cheaper than Great Stuff when you do the math?

  3. David P says:

    Not that they’re saying it’s cheaper, of course. But what’s the real advantage for small-scale jobs? Seems to me that the major plus of icynene and PU foam insulation is that it can be applied on a massive scale with relative ease.

    I’m going to go buy one of these things just for fun, though.

  4. Personally I won’t touch this stuff or great stuff as most contain a brominated flame retardant which is extremely toxic and a health hazard.

  5. Zathrus says:

    That’s the expanded volume, as per the FAQ on Dow’s website. So, yes, 1 cu ft.

    I can’t find info on the actual R-Value of this stuff once applied — all I can find is “high R-value” but not the actual number for given thicknesses.

  6. Fred says:

    A quick look at Dow’s 2 MSDS sheets does not show the bromine flame retardant – but plenty of isocyanate, polyols and chhlorofluoromethane (as propellants) plus lots of other cautions as one would expect.

  7. Zathrus says:

    Stephen, what on earth are you talking about? As Fred says, the MSDS shows no bromine-related chemicals in Great Stuff. Don’t spray it in your eyes. Don’t ingest it. Duh.

    And, frankly, even if it did contain brominated flame retardants, then you have far bigger issues if you’re trying to avoid them. Like the computer you’re using. Like the chair you’re sitting on. Your TV. Just about any cables. And a few dozen other commonly used items.

  8. What’s the volume of a can of great stuff? Man, this would have been GREAT if I’d discovered it two days ago when I was soundproofing around the edges of a new ceiling.

  9. McAngryPants says:

    OMFG!! I want/need the Froth-Pak 180 soooo bad.

  10. Mean old Mr Johnson’s mailbox will never know what hit it.

    (Nor will his car’s exhaust pipe.)

  11. George says:

    I had Icynene sprayed (professionally) into our upstairs addition a few years ago, and it’s been really great. This would be great for smaller jobs as I remodel older sections of the house. This seems to spray and conform to surfaces much better than standard “Great Stuff” type foam.

  12. Eric says:

    Tiger Foam is a little cheaper, also fire rated, which the Dow stuff is not. I considered insulating my mostly noninsulated rowhouse ceiling with poly foam, but it’s just not cost competitive with traditional insulation. Although maybe an inch of poly foam covered by a foot or so of cellulose might not be a bad idea.

  13. SuperJdynamite says:

    I looked into using spray foam insulation in a house I’m renovating but after consulting with some architects decided against it.

    With aggressively applied foam sealant it’s possible to over-seal your house. The perm rating of sprayed foam is so low that it’s effectively a vapor barrier (akin to polyethylene barriers — not a bulk moisture barrier like Tyvek). This is fine if you live in a year-round heating climate (i.e. warm side is inside), but if you live in a cooling climate or a mixed climate (e.g. cold dry winters and hot humid summers) having a vapor barrier inside isn’t always a good idea. In cooling climates an internal vapor barrier can lead to water vapor migrating inwards and forming condensation once it hits the vapor barrier.

    I’m not saying spray foam is bad, I’m just saying you need to consider climate, insulation and ventilation when picking an insulation strategy.

  14. Eric Dykstra says:


    According to a spec sheet i have here Dow claims a R-Value of 6.99 per inch.

    http://tinyurl.com/2v5s6b click the ” DOW: Froth-Pak 180/12″ link and it’ll download a pdf.

    David P,

    I think the main benefit of small scale use of Foam-Pak is really well illustrated in the post’s main picture. One quick pass with a medium fan nozzle and the junction between that ducting and the ceiling is sealed. “Great Stuff” applied topically can be sort of lumpy and that can allow for air leaks. Personalty I think it’s best if it’s used like an expanding caulking.

  15. Hank says:

    SuperJdynamite, I have a question.

    I live in Houston, and that is close to being a tropical jungle when it comes to humidity. Considering your thoughtful and helpful comments on spray foam, would rotating attic vents prevent the “over seal” issue on an attic ceiling, and walls? Would the foams perm value still set up a vapor barrier?

    Any help would be appreciated. Thanks. Hank

  16. Brau says:

    I can see myself buying a few of these kits, for sure. I bought an old home built before the advent of vapour barrier meaning it leaks air like a sieve. I have been looking for a DIY solution to sealing the walls from the inside as the exterior is in perfect shape. The cost of professional spraying, plus the need to have them do it all at once is very prohibitive and inconvenient as I only plan to renovate one room at a time by myself.

    Being informed about products like this is why I LOVE this site!!!

  17. Eric Dykstra says:

    Thanks Brua!

    Post some pics to the flickr group when you get started!

  18. SuperJDynamite –

    Yes, completely enveloping your home in a vapor barrier is asking for trouble, particularly since most of us experience those changes in weather called seasons. That said, using a product like this correctly is the key. You don’t want to spray over soffit vents for example, and you want to take care to leave space for air circulation where it’s needed and/or required by code. Ensuring that proper air circulation is maintained will prevent any of the condensation issues you describe.

  19. SuperJdynamite says:

    @Hank: “Would the foams perm value still set up a vapor barrier?”

    Controlling condensation in the attic isn’t difficult because, as Rick says, you have some extra air space above the insulation which you can vent to the outside.

    As for what to do with the walls I’d hate to give you bad advice, so I’ll give you some further reading and you can decide what’s best for your situation:

    Here’s a page from the DOE on the placement of vapor barriers.
    Another page from Building Science Consulting.
    Short Q&A about moisture behind a basement vapor barrier.

    A good googling will turn up tons of information.

    One thing to note is that the consumer foam sprays are usually Polyurethane based while the “professional” sprays are typically Polyicynene (or similar). These materials have very different vapor transmission properties.

  20. Bill says:

    I recently looked into this stuff to insulate the exterior of a fieldstone foundation. Let’s just say that the cost was prohibitive.

  21. sappler says:

    Does anyone know if this stuff can be sprayed verically or between floor joists? I am looking to insulate some pipes that constantly freeze, even with pipe insulation and fiberglass, and I thought this migh work better to completely conceal them. Any thoughts?

  22. Intrepid says:

    Two things to be mentioned:

    A comment on vapor barriers (not a recommendation, just something maybe someone should look into more)–

    Aren’t vapor barriers usually a big consideration with “fuzzy” insuation? If you have fiberglass, cellulose, etc. and are adding foam sealants, you have to consider the properties of the insulation you have in order to maintain their safety, efficiency, and effectiveness; all of those types have to have air flow to remove moisture, since air and the moisture it carries moves freely through these types of insulation–which is why Tyvek is a good choice. But if you are starting from scratch (and don’t have a mix of insulation types), maybe the requirements change, since you don’t have to remove moisture from the older types of insulation.

    On Froth-Pak’s fire rating–

    (The below wasn’t clear to me for months despite having read the page several times, it’s sort of obscured in footnotes but seems clear once you notice it.)

    Per http://building.dow.com/styrofoam/na/res-us/products/frothpak/index.htm

    The page suggests there are at least 2 categories of froth-paks (now). The Froth-Pak 12 (originally mentioned in this blog) appears to be more a sealant, and not fire rated.

    The FS stuff (maybe meaning fire safe) seems to fire rated. It has an aged R rating of 4.6, which is lower than the 6 someone mentioned in the comments, which may be for the non-FS variety. Unfortunately, the FS stuff doesn’t seem to be available in small packs (stupid Dow).


    What I’ve been looking for is a clear mention on a Dow page whether froth-pak is open or closed cell foam (polyurethane foams can be one or the other depending on the formula). As anyone who has looked into Great Stuff knows, Dow’s FAQ mentions it’s closed-cell, but then turns around and suggests its due to the skin that forms, which is perplexing given they recommend the product be trimmed if overfilled, thus often cutting away the skin, sometimes on either side. A lot of boat builder sites think the closed cell nature of Great Stuff is complete crap from direct but unintended uses of the foam.

    Anyways, back to Froth-Pak, Dow’s website doesn’t seem exactly forthcoming with practical info a lot of times. A lot of unaffiliated sites seem to have Froth-Pak as open cell, while a few mention it is closed cell. As others have mentioned, there was a Froth-Pak FAQ before, but I cannot seem to locate it and maybe Dow removed it.

  23. Tom says:

    SuperJ…your Architect is a moron. One sided logic. If the foam creates a true vapor barrier* (which it doesn’t), then what difference do the seasons make? If it stops moisture from going ‘out’ in the winter, it will also stop moisture from coming ‘in’ in the summer. To say it’s good one way and bad the other makes no sense. The foam is sprayed, and sealed, against the exterior sheathing, what is it going to condense on?

    *3″ of high density foam has a perm of <1, a true vapor barrier (6 mil poly) <.01

    Perm ratings aren’t the real issue of foam vs. other types of insulation. If you are using fiberglass, ANY moisture (humidity) will go right through it (along with the warm air that’s carrying it) and condense on the ‘cold’ side. You need a great moisture barrier to stop that. With foam, the high efficiency and lack of air gaps and leakage around the stud edges slows heat (and moisture) to a crawl. Any water molecules that can penetrate the foam, will pass right through the exterior sheathing, (or interior drywall ( the “Architect’s” point of contention)). Keep in mind the perm of foam is less than wood, and the R value of foam is greater, so heat and moisture are moving through the studs faster than the foam.

    Keep in mind this applies to standard density foam 1.5# or greater. Icynene type (open cell) foam, should have a true vapor barrier on the interior of cold climate houses.

    Froth Paks are generically closed cell foam, though there is an open cell ‘special foam’ product.

    No foam has a fire rating. It’s plastic. Just like your plumbing pipes, chair cushions, carpet padding. If it’s in your attic or walls, by the time a fire gets to it, that fire will have had to penetrate the drywall. If you are still around at that point, you’re already dead.

    Open cell foam ~ R-7 /per inch thick
    Closed cell foam ~ R-4 /per inch
    Both are air tight
    A styrofoam coffee cup has an ‘R-value’ of .5 A 1″ furnace filter ‘should’ have an R-value of 3 !

    29 years of spraying foam and I have cellulose in my attic. It’s still cheaper than foam on an R vs. R value

  24. Ryan says:

    Tom – I believe you meant Closed Cell is ~R-7/per inch thick and Open Cell is ~R-4 per inch thick

  25. jacob says:

    To start with I am a certified Spray Foam Application living in Toronto Ontairo. I have worked for the Union for years and also got certified by Icynene Company.

    R value depends on the weight of the foam, .5lb, 1lb, 2lb, 3lb.

    Open cell(half pound) if you apply it and leave it with the natural ‘crust’ on the outer edge it counts as vapour barrier (at least in Ontario Canada) however for the cost of vapour barrier I would apply it. It also is great to control humidity. Its more flexible than other weights(good if you have an old house that shifts) and provides sound dampening, however it has lower R value.

    Closed cell(two pound) also helps in humid areas and technically adds Structural Stability, 3lb even more so but its generally only used for flat roofing. In all cases spray foam insulation must be covered as it will degrade if exposed to the sun and is not fire proof, it will burn but only as flame is applied, it self extinguish if its the only fuel source. In most cases simple fire proof paint is more than enough to cover it and meet all building codes.

    as for health concern, spray foam insulation is a combination of isocyanate and a resin, the resin is different for each manufacture. However the off gas generated when you combine the tow (spray) is toxic. Charcoal particle filters in extremely well ventilated area is fine for this product however, at least for profession equipment, you should have a full face fresh air mask drawing form at least 50′ away. Many professionals don’t use this equipment and it does effect there health and lungs.

Leave a Reply to Fred Cancel reply

Your email address will not be published.