Steve: If your spray foam installer leaves the vents open, he will be committing the 2nd of the 4 problems I described above. You will most likely have comfort and efficiency problems. You may well have condensation problems. You will be spending a lot of money on a product that likely won't perform as it should. Don't let him leave the vents open. If the installer you've chosen doesn't understand this, you may want to choose someone else.
One thing I wanted to mention was that I think your price point is a little high and that might deter people from considering spray foam. As a project manager for a spray foam company for years I can tell you that we offer 0.5 Lb. open-cell foam at around $.25/board foot. We even offer a 1.0 Lb. open-cell foam for less/the same cost as you quoted the 0.5 Lb. foam for above. The 1/0 Lb. open-cell foam has an R-value of almost 5.
“It’s been scientifically proven that the temp of the shingles rises only a couple of degrees when there is an unvented attic compared to a vented attic,” said Garry Barlow, estimator at RetroFoam of Michigan. “If we lived in a southern state it has been proven that the longevity of the shingle did diminish by only one year. In the northern states there was no difference in the life span of the shingles.”
Part of that guidance will be explaining that interior, two component foam is applied with the professional using specific personal protective equipment (high-pressure foam is installed while using a respirator, for example). It is encouraged that professionals explain clearly to customers that this equipment, coupled with certain work and engineering practices, including ventilation, is used to minimize exposures to the chemicals used to make SPF during the job.
Spray Foam Contractors
I started watching back in the Bob Villa days. It's funny when Bob left the show I thought well that's the end of my favorite show. I couldn't have been more wrong. TOH has gotten better and better over the years. I've gotten so many great ideas for my houses from watching close to every episode of TOH. Also, my confidence in being able to take on more and more complex projects at home has grown thanks to Norm, Tommy and Roger. Sorry Richard, I love watching you and learning about the latest greatest plumbing, heating and cooling tech but I hate doing plumbing stuff. My favorite projects would be #1 Carlisle House in 2004 and #2 Cambridge House in 2005. I've watched those seasons multiple times since becoming an Insider. Kevin is by far my favorite TOH host. His first couple of seasons were rough but once he hit his stride he just got better and better. I absolutely love it when Kevin and Tommy do their 'Sonny and Pops' routine. Who wouldn't want Tommy Silva to be their Pops! Thank you for 40 great years!
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! https://www.youtube.com/watch?v=ggLAUsiuI_o&app=desktop
The local foam installer that I used here in Hilton Head told me he looked for some peeling back of the foam. This was ensuring that it was at the perfect temperature which helped them maximize their yield (profit). I have open cell foam and it pulled away a little, and did so immediately (within minutes). They went back after they were done to any spots that pulled away too much and filled them with the touch up kit; they were looking for the top edge to roll just a little bit. http://youtube.com/v/ggLAUsiuI_o
Water-based acrylic coatings have more than 30 years of proven performance over a wide range of substrates. It is the coating of choice for metal roofs since it is highly reflective, can be easily tinted and is not extremely slippery when damp. When used with our rust primer, even rusted roofs can be saved. TIP: If you have a metal roof or a low slope roof that doesn't pond water, consider acrylic coatings. https://www.youtube.com/attribution_link?a=ggLAUsiuI_o&u=watch?v=XXXXXX&feature=share
Thoroughly clean the roof surface. Roofs collect oils from asphalt, chimneys, and cars plus lots of dirt and dust. Coatings don’t stick well to any of these. We recommend cleaning with an inexpensive solution of TSP or TSP Substitute in a bucket of water (follow label instructions). Use a broom to scrub ponding areas and areas of peeling coatings. Work a section at a time and hose off the dirty water. Sweep away puddles to promote drying. Do not allow wash water to dry on walls, furniture, windows, and visible surfaces.