I don't even want to ask this question but... several years ago we hired a local contractor to spray high density foam on the roof deck and walls of our unfinished 2nd floor. We realized that the job was done poorly and cut an access into the attic space to assess things. We realize now that they spray foamed directly to the chimney (no flashing). The chimney is currently used for a woodstove and DHW venting. The DHW will go away but wood stove will remain. My question is, how bad (unsafe) is this? I have found information on foam exposure to fire but have not been able to find anything about temperature ratings in general (i.e. what happens on prolonged exposure to high temperatures). http://www.youtube.com/e/ggLAUsiuI_o?app=desktop

We are turning our roof into an unvented roof assembly by raising the roof and blowing in SPF. We are planning to leave the existing vapor barrier down but remove the fiberglass batting and then adding 6" of SPF in all the cavities, to completely seal and insulate the house. Should we have any concerns about doing it "upside down" and not spraying the foam directly to the underside/sheathing of the roof?

How Much Is Spray Foam Insulation For Attic

Check with the coating manufacturer who may be able to suggest applicators who have used their products and have familiarity with the application. Another option would be to interview contractors and ask specific questions about their proven ability to install roof coatings. Contractors affiliated with the National Roofing Contractors Association (NRCA) or local roofing contractor trade associations typically are more knowledgeable. Consult those groups’ websites for contractors.
The insulation at eaves level will leave your loft area comfortable for use and free from condensation. By installing the insulation at rafter level, it keeps the loft void warmer and prevents condensation build-up, which can otherwise occur when increasing insulation at ceiling level. The warmer, drier, cleaner roof space eliminates the risk of pipes and tanks freezing. http://m.youtube.com/embed/ggLAUsiuI_o
This is in great contrast to my friend's experience. Her attic spaces were sprayed and the foam is actually pretty, and I was in her attic 6-7 days after it was sprayed and could hardly smell anything when I stuck my face up to the foam. And she did not have to clean up one speck of dust during or after the spraying. I got the name/number of the guy from her who managed her attic project, but between the time he did my house and the time he did her house, he was let go from the company who did her attic and hired by another company. He assured me everything would be the same, etc., etc., and I had no reason to believe anything had changed, but the sprayers who did my house later admitted they had never sprayed an attic before and I also found out that the foam used in my attic was from a different manufacturer. Neither my friend nor I had any idea this guy was with different company then, until the week after they filled my attic with off ratio foam, and my home with toxic vapors.  
We have a 22 year old home located in southeastern georgia where the humidity is very high. In the past 2 weeks our floors have started buckling all over. We have a vented crawl space and the old insulation is drooping from moisture and the wood is wet. We are debating between the "encapulation" method or the spray foam method to repair this issue. Which would you recommend? https://www.youtube.com/watch?feature=youtube.be&v=ggLAUsiuI_o
I had a hole in the drywall in our bathroom that was about 2 in x 5 in that I used Great Stuff to fix. I am impressed with the characteristics of the filler. It filled the hole completely in a few seconds of application. I will warn anyone using it though to make sure you don't fill the hole entirely flush to the wall because this stuff continues expanding after you apply it. I didn't think about that but no big deal really because you can sand it which is exactly what I did, and then applied spacial and paint and it is almost as good as new. For the price this was a heck of a deal because I only used a tiny amount and now am left with nearly a full can. I guess I will have to find somewhere else to use it now. Great product, ... full review
I have to insulate my walls at the end of this week. That does not give me time to procure slow-rise foam, so my stud cavities will be filled with foam before I'm ready to fill the corner voids. I will not be able to drill straight through the corner studs. Instead, I will have to remove material where the studs meet. What sort of tool do you envisioning me holding while I create space to pump foam into my 1972 corner voids? 

Spray Foam Existing Wall

One of the high-tech insulation products being utilized these days is a foam-spray product called "Icynene," which is a foam that starts as two liquid components (a and b, if you will) that are heated up and sent through two hoses and meet at a tip of a gun where the magic begins. This is a thin film that expands to 100 times its volume in eight seconds, when it's permanently set up.

I recently did a remodel project for my basement using spray foam insulation. The original builder has used fiberglass, but I wanted the best insulation i could find. We chose closed cell foam because it blocks moisture from getting into the house. It took one day to install and was fumey for about 3 hours. It was pretty cool watching it being done. It comes out as a liquid and then expands rapidly into a foam. It's quick! Then they took a types of saw to shave it flat with the wall studs so we could then go ahead and drywall.

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