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.
I used this product to seal and insulate my rim joists as I am finishing the basement. The builder used R13 batt insulation when we built the house 3 years ago. I use a dehumidifier to control moisture in the basement which is below grade. The setting I use is 55%. The dehumidifier kicks on periodically and requires emptying every few days. Since using the foam all around the house on the rim joists and sill plate, the dehumidifier has stayed at 50% for over two weeks since spraying and rarely turns on anymore. I also put the original R13 batt insulation back up after the foam cured. http://www.youtube.com/watch?v=ggLAUsiuI_o&app=desktop

I've seen this only once, and it was with closed cell foam, but I've heard of it happening with open cell foam, too. I don't know the details, but I've heard it could result from a bad batch of chemicals, improper mixing, or too high a temperature. Whatever the cause, it's not a good thing. The photo below shows how the spray foam pulled away from the studs. A little bit of uninsulated area like that adds up to a lot of heat loss/gain when the whole house has that problem, as it did here.
I have never used foam insulation before and this was easy for me to use right out of the box. I had a 4'x8"x8" cavity in my basement that houses a waterline. When the previous homeowner installed this they put no insulation in at all and being that it's an exterior wall in the basement and I live in the Midwest that thing was pushing so much cold air in it was incredibly uncomfortable. Out of the box and job completed in about 5 minutes. Stopped all drafts and created a nice 2" barrier on the wall in which I will install some extra bat insulation over it. 4 stars because the spray isn't very good passed 6-8" from the surface. Make sure you can reach the surface you want to coat. Great for small jobs! http://www.youtube.com/watch?v=ggLAUsiuI_o&feature=youtu.be
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?

Spray Foam Garage


Sta-Kool 800 15-year White Elastomeric Roof Coating is Sta-Kool 800 15-year White Elastomeric Roof Coating is a high quality very flexible white acrylic latex roof coating. Coverage is 50-75 sq. ft. per gallon per coat. Two coatings are recommended. This performance product resists cracking and peeling while offering tremendous durability. This long lasting formula forms and excellent highly ...  More + Product Details Close

Spray Foam Roof Insulation

×