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Community and Q&A

FrothPak/Touch n’Foam Closed Cell Spray Foam

lornec10 | Posted in Energy Efficiency and Durability on


We have rim joists to insulate and I’m hoping to do it myself. 

FrothPak has a frothpak insulation and a frothpak sealant. They both list rim joists as an option. Does it matter which one I use? I think the sealant is only for penetrations and junctions but the insulation can do double duty. 

Also, any suggestions on FrothPak vs. Touch n’Foam? 

Also, any comments on the ambient air temperature required and how much wiggle room there is? 

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  1. blacksturgeon | | #1

    I know that the 2 component FrothPak is finicky. The tanks themselves must be warm during application. If they are not, relative rates of discharge from the “A” tank and the “B” tank can change and give a poor mix. I’ve seen lots of kits with one empty tank, while the other tank still has substantial material in it. Not much wiggle room with these. You have to follow their application guidelines very closely for satisfactory results.

    1. lornec10 | | #6

      Thanks, John. Any knowledge of the "sealant" vs insulation for Rim Joists?

      1. blacksturgeon | | #8

        I’m not familiar with their “sealant” product.

  2. jonny_h | | #2

    I'm not sure what the frothpak sealant is, but I bought an insulation kit a while back -- then scared myself off of it before I ever used it (near Ohio and want a good deal on a frothpak kit? :P )

    Read the instructions & MSDS carefully. It's pretty tricky stuff to get right, I wouldn't assume much wiggle room on recommended application conditions. Make sure you have a real-deal respirator with the appropriate filters (ie, half-face or full-face, not a dust mask), good gloves, ideally a full-body suit, and good ventilation. One of the components is basically a jug of MDI, which as wikipedia says is " the least hazardous of the commonly available isocyanates, but is not benign." One nasty little thing about diisocyanates is that they're sensitizing agents -- sometimes exposure (even skin exposure) to them can drastically increase your sensitivity to future exposure and/or basically cause asthma. Oh, and the blowing agent is R-134a, which has a global warming potential of about 1400.

    As I remember from the application instructions, you also basically need to be ready to gogogo as soon as you start. If you stop spraying for more than a few seconds, you need to change tips on the gun because it'll set up in the tip. You need to make sure the mixture is just right, or it won't cure properly (Frothpaks are theoretically set up to just spray the proper mixture automatically -- but this is probably dependent on the application temperature being correct!)

    It's definitely possible to do it yourself, safely. I already had all the PPE required, and have a trustworthy friend who also had all the required PPE and respect for safety. But, in the end I decided why mess with something that invokes so much risk when there are other ways to accomplish what I needed to do. I'm not trying to tell you not to use it, though -- just don't look at a 2-part spray foam kit the same way as a can of great stuff (which by the way is also diisocyantes-in-a-can and should be used with good ventilation, it's just not quite on the same scale and doesn't use high-GWP blowing agents).

    EDIT: Apparently they've recently changed the formulation of Froth-pak insulation to a low-GWP / HFC-free blowing agent. Glad Dow made this change! Look for the new version if you decide to use this. The rest of my concerns about safety still stand, though.

    1. lornec10 | | #5

      Thanks for the reinforcement of a full body tyvek suit! No skin exposed! I don't like messing with things I can't pronounce.

  3. Expert Member
    BILL WICHERS | | #3

    Get the two tanks warm at least a few hours before you start work. At work, I put them on top of a transformer overnight. I've put them in a bathroom with a space heater and the door closed before too. Ideally you want them warm to the touch, but not hot, which usually means in the 80-85F range or so. It's important to hold them at that temperature for a few hours so that the material inside gets completely warmed up. The tanks will cool off as they're used. It is VERY IMPORTANT the tanks don't get too cold during use or you start having issues with not getting all the material out, or problems with the mix in extreme cases.

    You'll want to have extra tips for the spray gun on hand for the application. You get VERY LITTLE time not spraying between sprays before the tip clogs up. You have to work quickly. I recommend getting everything you want to spray ready to go before you start, plan what you're going to do before you start, then when you do start, GO GO GO until you're completely finished. No stops, no breaks, nothing but spraying until you're done, moving from one spot to the next as quickly as safely possible. Allow for dragging the tanks around too as they're not lightweight when you start.

    I recommend some protective equipment. A respirator (a real one with filters, not just a mask) is a good idea, but be sure to use the correct filters for the materials you'll be working with. A full tyvek suit is also a good idea, and you need eye protection.


    1. lornec10 | | #4

      Thanks, Bill! It makes sense to give the tanks plenty of time to warm. I will give them plenty of time in a warm space. You make it sound like I should also be prepared to keep the tanks as warm during application. Maybe I find a heated blanket or something. I am going to borrow space heaters and keep the basement to applicator suggestion. New England is cold now, hence the urgent need for better insulation which I overlooked all summer.

      I will GO GO GO. Good tip on dragging the tanks and their weight.

      I have all PPE. The stuff doesn't sound pleasant.

      Do you have suggestions on the froth pak sealant vs the insulation? I have a question out to the manufacturer but the local store has only sealant.


      1. Expert Member
        BILL WICHERS | | #10

        A blanket on the tanks is counterproductive. The tanks get cold during use from expelling the material inside. It’s similar to how a can of canned air gets cold when you use it, or how a propane tank gets cold while running your grill. The tanks essentially suck heat from the air around them, and a blanket will reduce that.

        The insulation vs sealant might be a naming change. I’d check with the manufacturer about that.

        The material isn’t super hazardous, but it’s extra super sticky and you don’t want it to get on anything it should, such as your skin. Imagine a high powered squirt gun filled with super glue. That’s essentially what you need to defend yourself from.

        BTW, it is worth checking with a spray foam contractor. You might find that the contractor isn’t much more expensive than the kits, especially if you can get flexible scheduling your project so that the contractor can squeeze you in between larger jobs.

        One last thing: you get the best results when the surface you’re spraying against is above 50F. If the surface is too cold, you can have problems.


    2. Expert Member
      NICK KEENAN | | #11

      To add onto Bill's excellent advice:

      A 300 BF kit weighs about 120 lbs. Unless you can do the whole job without moving the tanks you need to figure out how to move them. I used a 4-wheel cart, like a kids red wagon but bigger. This was also the perfect height for standing on to get into the corners of the rim joists.

      I found it helped a lot to hold a rehearsal before spraying -- walk through the whole job with the nozzle in your hand. This helps you plan a route where you can spray continuously. One of the things I learned in rehearsal was my wagon needed to be backed into the corners .

      One of the worst things that can happen is if one of the tanks falls over. You'll just get propellant, and your mixture will be off and it's hard to get it right again. Tie the tanks to the wagon.

  4. Patrick_OSullivan | | #7

    > We have rim joists to insulate and I’m hoping to do it myself.


    I've thought about doing it myself before as well, but fortunately talked myself out of it multiple times.

    Those kits really aren't that cheap. When you factor in the learning curve, prep/site protection, PPE, and your time, you'll find it makes sense to hire experienced spray foam installers with a proper spraying rig on a truck.

    1. Expert Member
      NICK KEENAN | | #9

      Yeah, my experience is that the cost per board foot is less with the guy on the truck. The DIY kits only make sense when you have too small of an area to make it worth the guy's while.

  5. mgensler | | #12

    I've been using the frothpak insulation kits. The come in a little bit larger version (650) and are closed cell foam. Not sure why they sell two different versions. Frothpak has great nozzles that mix really well. I'd recommend them over the other kits even if they cost a bit more. If the components don't mix properly, you will potentially have a mess on your hands and a waste of material.

    I'd also highly recommend heating the tanks in hot water especially if they have the hoses attached. When using a space heater, one of the hoses melted and started leaking on me.

  6. bob7 | | #13

    Personally, I've used a heating pad in a cooler to keep the tanks warm. You can put the tanks in hours before you want to start, set the pad to medium or low (it depends on the heating pad, of course). Then just move the cooler around....

  7. plumb_bob | | #14

    All good advice. I just decided to not use a DYI froth pack!

  8. oldbungalow | | #15

    Why not cut 2" foam board to press fit then go back with canned foam to seal? More work but safer and less consideration for temps and stuff.

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