Spray foam insulation, when properly installed is both an air barrier and when closed cell foam is used at the proper depth a vapor barrier!  Before hiring any contractor you should establish the brand of foam being used and verify that with the named manufacture.  Please ask for ESR reports and MSDS sheets on any foam being installed in your home. A couple areas where you might consider spray foam insulation include:
Henry 587 Dura-Brite White Elastomeric Roof Coating is Henry 587 Dura-Brite White Elastomeric Roof Coating is a premium high solids formula offering better weather protection solar reflectivity and longevity than economy grade reflective roof coatings. Cured coating forms a permeable membrane which prevents liquid infiltration but allows moisture vapor to vent or breathe out of underlying substrate. Recommended ...  More + Product Details Close

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.

How Much Better Is Spray Foam Insulation


Although spray polyurethane foam has many advantages over other types of insulation, spray foam installation isn’t foolproof. Some builders have reported problems with sloppy foam insulation. For example, some installers have been known to begin spraying before the chemical components are up to temperature, which can affect component mixing and foam performance. When components are poorly mixed, or mixed in the wrong ratio or at the wrong temperature, cured foam has been known to shrink away from rafters or studs, leaving cracks. Some installers rush through their spraying, resulting in voids.
I have used the Froth-Pak 200 to air-seal rim joists--the area above the foundation wall in a basement. The first time I used it I did not shake the canisters well enough and the foam did not cure properly. Don't just shake the box for a few seconds. I take the tanks out of the box so I can shake/invert each tank for a minute or two. You will be able to hear the chemical sloshing around in the tanks. Also, don't ignore the recommended temperature for application--around 75 degrees F.
Some states, municipalities and utilities have programs. Check with your coatings manufacturer for further information. As a membership benefit, RCMA provides maintains a database of current information on rebates and tax credits for installing reflective roofs. RCMA’s customized search tool can be used to find the most up-to-date listings of reflective roofing financial incentives available.
Wallice Foam did a fantastic job on our new home and my little she shed. While in the process of backing in our extremely difficult driveway with their unit our mailbox was accidentally knocked over, and they were there within three hours that same day and brought a crew to repair and set back up our mailbox, we greatly appreciate there honesty and their willingness to repair our mailbox and so promptly. We would highly recommend this company for any foam insulation needs you may have. The *****’s

Silicone coatings are typically produced by adding a catalyst and solvents to a silicone base. Because the silicone is a natural material, these coatings are bio-degradable. They can be applied to a roofing system using many different techniques, including spraying or rolling. Silicone coatings are available in many colors, including reflective white and translucent.
I just received this and it worked well for me. It works well for small gaps (around windows, between studs), but probably not the right tool for larger gaps (>1" or 2"). If used in larger gaps, it works OK if it is layered in. Spray a little and wait for it to set, then layer another on top, etc... This is pretty much noted by the seller. It is pretty much exactly as described and priced right, so 5 stars. If you need to do larger gaps, buy 2 part. http://youtube.com/v/ggLAUsiuI_o
However, coating asphalt shingles and built-up composition roofs requires more caution. The National Roofing Contractors Association’s (NRCA) director of technical services has stated "The roofing industry is aware of a number of issues that could have negative consequences for field application of coatings over asphalt shingle roof systems. Anyone considering this type of application should be aware of the concerns so they can weigh them against the benefits claimed in coating product promotional materials."[2]
I am an Architect in Toronto. I am designing a new roof addition to a row house building. Because of existing conditions and the shape of the new roof. It may be easiest to use closed cell spray foam within the areas of the joists. My question is when spray foam is used in this situation do I need to worry about how the joist members may be thermal bridges? It is not common to provide a little bit of rigid insulation to protect the joist members? The additional layer of outboard insulation will require an extra layer of plywood above the insulation which will add to cost. 

How Much Spray Foam Garage

×