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 Coating 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?
Open cell spray foams are less common and have a lower resistance to heat flow than closed cell spray does. Open cell spray foaminsulation expands when it is applied, which allows it to be installed in hard to reach areas, such as small wall and ceiling cavities. Open-cell spray foam is typically cheaper than closed cell foam is, but it is more permeable and vulnerable to fire hazards. Spray Coating Services As this example illustrates, it's important to seal the envelope completely. One of spray foam's biggest selling points is its air-sealing ability, but it can't seal places where it's not sprayed. One of the nice things about using spray foam in new construction is that you can do a Blower Door test before the drywall goes in. Even better, you can test for leaks with a fog machine. Spray Coating