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?

After researching this, Im curious about a method called poor mans sprayfoam where foamboard is cut to size between studs and sprayfoamed around the perimeter. Aside from the labour doing the job yourself, the cost seems comparable, is one better than the other? What about the quality of the canned sprayfoam around the perimeter? When i see sprayfoam done, it is never a full depth of the studs, so you would get 2.5-3 inches in a 3.5" (2x4) wall. Any thoughts? 


Ames® elastomeric waterproof roof coatings are premium coatings that seal out moisture, renew old surfaces and even save energy. We have products specifically formulated for all types of roofs including; Wood, Tar, Metal, Rolled Roofing, EPDM Rubber, Foam and many other surfaces. From flat roof coating to plywood roof coating, Ames’ liquid rubber roof paint coatings form a waterproof seal to preserve and protect your roof. Our white roof coatings reflect sunlight, substantially reducing roof temperatures and helping you save on cooling costs. Ames® products are environmentally friendly, water-based, non-toxic, VOC-free and can be cleaned with water. If you’re looking for how to seal a flat roof, pitched rolled roof, or just about any other kind, our elastomeric waterproof roof coatings can help you get the job done.
There are two main types of spray foam to consider: open-cell and closed-cell. Open-cell spray foam has a lower R-value per inch and because of this, typically a lower price tag. The soft, low-density material is used for interior applications. Its high permeability allows for moisture to pass through, which contributes to bi-directional drying of the assembly, but it may not be ideal for all applications or climates.  http://www.youtube.com/watch?v=ggLAUsiuI_o
It also has a great waterproofing ability that can shield the roof’s membrane from water and moisture damage. You can also count on the liquid roof coating for its outstanding performance for a wide range of applications and uses. This product can be used at tears and seams as well as in sealing air conditioners and venting systems and anywhere else where rubberized coating is needed.
If you’re looking for an effective and efficient Elastomeric Roof Coating, you might want to consider the Kool Seal roof coating. This product comes in a 115 fl oz container and is white in color. It is easy to apply and use that it can stick well even in the harshest weather conditions. This product offers maximum clinging to the RV roof despite the temperature. You can also rely on its effectiveness no matter the type of weather.
R-value, the thermal resistance measure of insulation, varies between all insulation products whether they are fiberglass, cellulose, open-cell spray foam insulation or closed-cell sprayed-in foam insulation. Generally speaking the rule of thumb is the higher the R-value, the greater the insulating power.  Focusing on spray foam insulation materials, there is a difference between the two main types. According to industry publication, Fine Home Building, the R-value for open-cell spray foam is between R-3.5 – R-3.6 per inch. However, there are open-cell spray foam insulation products actually offer R-3.7 per inch such as Icynene Classic and Icynene Classic Max. The open cell structure of low density foam insulation means the R-value is lower than its closed-cell counterpart. Nevertheless, open-cell spray foam does offer superior and consistent thermal insulation and air sealing properties.

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.


RE: my June 12 post...We went ahead and had the attic sprayed with a Soy-based product. Stayed in a hotel for 3 nites. Still smelled a little bad but that's gone away over time. I'm very glad we didn't use the other foam as even that much outgassing of a petrochemical could have sent my wife to the hospital. Unfortunately, the spray crew didn't speak English(at least not to me) and were kinda lazy, so they ended up spraying over some can fixtures from the kitchen below that were not insulation-contact rated. So I hired an electrician to come out, pull down the cans, pull out what he thought was an appropriate amount of foam to create a big enough air space and then re-install the cans. I billed the firm for the electrician plus an extra night we had to stay in the hotel and they paid, no questions asked. Guess they knew they had screwed up.  
Empire Spray Foam is conveniently located in North Texas and proudly serves the Tarrant, Dallas, Denton, Wise, Parker, Hood, Johnson, Ellis, Kaufman, Rockwall, and Collin Counties with high quality spray foam and coatings designed to meet the needs of homeowners and businesses. Whether you are looking for energy savings, structural reinforcement, or weatherproofing, we have the solution. Call today to discuss your spray polyurethane foam options 817-516-2014. http://www.youtube.com/watch?feature=youtu.be&v=ggLAUsiuI_o
I believe customer education is a key to understanding what goes on inside your walls; where a mere 6 inches can separate your comfortable living space and the bitter cold of winter. Some structures are slowly being destroyed by way of insufficient or improperly installed insulation products that do not take into account simple building science. This is where we can help; I believe we can make a difference in the lives of people that live and work in this northern climate.

c) Make sure that the over expanded access is properly removed from the walls. We had a junior cutter taking too much off by bending his saw into the cavity. Look closely at the inside wall corners, and ceiling/wall corners to make sure that the foam is properly removed flush with the studs. If it has not been cut back flush it may lead to uneven drywall finishes .

Where To Find Spray Foam Insulation


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:
Roof coatings made with acrylics, urethanes or asphalt soften under the stress of ponding water or snowpack. Eventually, these roof coatings will bubble and peel away from the substrate, leaving your roof vulnerable to leaks, rot, and decay. However, GacoRoof’s 100% silicone formulation is designed to stand up to whatever the elements dish out. Silicone will withstand areas of ponding water without softening, bubbling or peeling from the substrate. Acrylic, urethane and asphalt roof coatings decompose and wear away from the stress of harsh sunlight, UV rays, and freeze-thaw cycles.
Heatlok®, is a high-performance, versatile spray foam insulation designed for residential construction. Its unique formula incorporates recycled plastic bottles and renewable oils to create high-performance, closed-cell spray foam insulation. This polyurethane insulation combines multiple control layers into a single application, saving homeowners both time and money in construction costs. With our innovative technology, Heatlok is developed with 14 % renewable and recycled content, and is the ideal choice for residential construction.

Spray Foam Garage Door


The drawback to spray foam insulation is it's been known to cause certain health issues such irritation of the eye and the gastrointestinal and respiratory tracts. Direct contact can cause inflammation to the skin, and some individuals have been known to break out in a rash on the arms, chest and neck area. Spray foam insulation has also been linked to a few cases of hypersensitivity pneumonitis. This condition can cause:
Note:  A board foot is defined as a 12" x 12" square at 1" thick. Actual output can be affected by a number of factors including temperature and humidity. The theoretical yield has become an industry standard for identifying certain sizes of two component kits. Theoretical yield calculations are performed in perfect laboratory conditions, without taking into account the loss of blowing agent or the variations in application methods and types.

Where Can I Buy Spray Foam Insulation

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