Do yourself closed spray foam in a can….is it legit?
Ryan_SLC
| Posted in General Questions on
Hi,
I am having a spray foam contractor quote me today on my cathederal ceiling. Thanks to cookies and tracking, Amazon alerted me to canned closed cell spray foam as a diy.
Is this a legit way to get my required R38 for building inspection, to do it myself from a can?
Let’s forgive all possible application failers like falling off the ceiling, etc. If it is in a can, mixes fine, I apply it fine…did I just save a grundle and will it pass inspection?
Thank you!
Ryan
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Replies
To pass inspection it needs to have an R-value on the can.
I have a review of the FoamBeak and some Amazon spray foam here:
https://www.greenbuildingadvisor.com/question/review-of-the-foambeak-nozzle
awesome. Thank you!
Thank you!
So it needs to list an R-Value, but if I read it right, the stuff you used didn't have it listed?
Correct.
I haven't used that particular product, but I have used the Kraken Bond stuff which appears to be very similar to what you linked to. I used the stuff as an experiment, in part to answer some questions posted in these very forums. Here is what I found:
The spray foam is like Great Stuff, but in a much larger can, and it seems to expand more. It's tricky to apply, but after working with it, you can get a reasonably decent application if you take care to do a nice job. You HAVE TO use their foam gun though, since their tips don't fit on the regular Great Stuff gun.
My experience was that this stuff sets up similar to regular Great Stuff, so not as hard or dense as "real" two part closed cell spray foam. The stuff in the can is a one-part foam, and is NOT the same as the stuff you'd get from a FrothPak kit or from a commercial installer. I found the stuff in the can to work pretty well for sealing up larger areas than regular Great Stuff can handle, but I wouldn't use it for a large area like an entire wall or a ceiling. There isn't really a big cost savings for the stuff in the can compared to a FrothPak kit, and the FrothPak kit gets you "real" two-part spray foam. I've found (based on experience at work), that the FrothPak kits are pretty expensive for what you get compared to having a contractor come in and spray foam something, so I only consider the FrothPaks a good option for smallish jobs like a rimjoist or small section of ceiling. For any medium size and up jobs, a contractor will probably cost about the same, or less, and will likely do a better job due to their experience.
I wouldn't recommend using the stuff in a can for a large area. I think you'll be frustrated trying to do that, and I wouldn't expect you to get nearly as good of an insulating job as you'd want (i.e. batts would probably perform as well, or even better, than the stuff in the can). If I only had a stud bay or two to insulate, then I'd consider this stuff. If you're doing an entire room or more (a big enough job to be needing to get things inspected), then I'd get some commercial quotes and maybe consider a FrothPak kit for smaller jobs.
I'd use the stuff in the can only for larger areas needing air sealing only, and not rely on it as the primary thermal insulation. I used my stuff to seal the ends of batts in a series of rafter bays to form an air barrier over the end of the batts between the underside of the vent baffle, the two rafters, and the drywall below. The canned stuff worked pretty well for this, although I didn't have much luck getting a nice, even layer. I could probably have done better with more practice (and in an easier to access area than the attic I was working in).
The stuff is a good product, but in my opinion it's not a good option for insulating large areas, due both to cost and to ease of use.
Bill
Wish there was a thumbs up button on the forum. Thank you!
8'WX12'L addition with cathedral ceiling. So pretty small with LOTS of rafter framing (inspector said they over built by a lot).
I guess we wait to hear the quote, but if eye watering...just a no go or proceed with our blessing and can't wait to hear how it didn't work well? :D
So probably around 180 square feet of roof? If you get one of the the 600 board-foot FrothPak kits that should do a thickness of 3.3 inches. That's about R-20, put regular 2x6 batts after that and you have a R-39 assembly that is safe from condensation. Spraying out the FrothPak will take 20 minutes, you'll probably spend longer getting your PPE on and putting down something to protect the floor.
The FrothPak will be about $1000, the same amount of spray cans probably $750. I'd say it's worth it to spend the extra money for the better quality foam and the ease of application.
You should also call around and see what a spray foam contractor charges. I haven't had it done in a while but it always seemed to be about the same cost as the DIY kit for anything but the smallest jobs.
I didn't find the canned foam to provide rated amounts of coverage, it didn't seem to go as far as claimed. The FrothPak kits, at least in my experience, give you much closer to rated coverage IF you warm up the two tanks prior to spraying (spraying with cold tanks seems to be the biggest cause of problems people have with these kits).
I've used lots of the FrothPak kits and never had a problem, as long as you start spraying into a bag a bit to get both tanks flowing, and don't try to eek out the last little bit at the end, either, in case one tank runs out first.
The big issue I usually see is that commercial contractors are often around the same price as the FrothPak kits, sometimes cheaper (especially for larger jobs). Where I see the FrothPak kits come out ahead is on difficult jobs with little foam required, such as rim joists in a crawlspace. DIY saves on labor on the complex jobs, commercial contractors save on materials on the larger jobs. ~180 square feet is a small job, but it's probably also very easy (being a ceiling), so it's still work getting some commercial quotes.
One big advantage to the commercial contractors is they won't come up short on material. If you run out with one of the FrothPak kits with just a foot of space left needing insulation, you're stuck using the canned stuff.
Bill
Every time I cost out DIY vs professional, it's a wash, or more. The folks I use locally have a proper spray foam truck with preheated chemicals, temp monitoring etc. Zero issues, and not a single issue so far with uncured foam, VOC, cracking etc. They know their stuff.
I would strongly recommend not doing DIY as your spend will be similar, but there is a decent chance you'll have issues, and have to remove and have it done by a pro anyway. In that case, a professional will look a fair bit less expensive :-)
Would you be better off having the framers put some 2x? Below the rafters to extend their depth and then use r38 batts? I am not sure if your roof is vented or not which may also make a difference.
So they did 2x6 and then did fur down with 2x4. So I am setting at a solid 8" bays.
GC's roofer did not vent. I am sure to have him do the quoted insulation does not involve fixing that to code, so it was done wrong, or will require more upcharge on fixing the roof.
So quote for the 190sf just ceiling was $3K for 6 inch at R-40.
That seem normal?
If so, that's 1/8 of the build. That's rather disappointing.
6" is closer to R36 in reality. You're up around $3 per board foot with that quote though, which seems a bit high to me BUT you have a very small job, and it's the very small jobs that get the highest price per square foot. Small jobs have a bigger component of the overall cost tied up in setup, cleanup, and getting the truck and crew to your site. If you had more square footage to cover, you'd probably get a better price per square foot.
I'd get a few more quotes. I'd also ask the contractors if you can get a better price by being flexible with scheduling your project. For small jobs, I'll sometimes ask my contractor for a better price, and let the contractor come do the job on 24 hours notice (sometimes same day), and just say "do it sometime in x month". That lets the contractor squeeze you in around other jobs, without having to commit to doing your job at a specific time. This makes things more difficult logistically on your end, but easier on the contractor's end, and if you can work with that, you can probably get a little better price.
Bill
I think you are exactly right.
Just did a phone quote for 7 inches at 1,700.
Now I'm entering just 500 over what the GC was going to do wrong with batts.
That's 1.27 a board foot, cheaper than you could do it yourself. Make sure it's closed cell foam. Also make sure they actually do the agreed-on thickness, those guys are notorious for shorting the foam. But otherwise I say go for it.
Thank you very much! He actually suggested going near full cavity and not doing batts, so should be easy to see...but that's a great point to watch for.
Thank you!
Right, if it's equal or cheaper, no sense in doing it with lots of possibility to do wrong and then have inspector and myself disappointed with me. :)
It's fairly common to do closed cell for vapor control, then fill the remainder of the cavity with open cell for a "full fill" of spray foam. That's often a better option than trying to stuff batts into irregularly filled (due to spray foam) cavities.
Bill