The video below is from a house near Charleston, South Carolina that I visited recently, and you'll see that the homeowner in this case didn't get his money's worth. I knew immediately when I walked into the attic that something was wrong because it was hot up there. In a properly insulated spray foam attic, the temperature won't be much higher than the house temperature. 

25 years of field study and thousands of satisfied customers have made Liquid EPDM Rubber the roof repair solution for many applications. Liquid EPDM Rubber is so versatile that it can easily be applied to metal, rubber, fiberglass, concrete, wood, fabric, foam and many other surfaces. Liquid EPDM Rubber Coating has proven to outlast acrylic, urethane and elastomerics by 4 times. There may be lower-cost products on the market but none that have the long-term durability, waterproofing ability and tolerance to extreme temperatures like Liquid EPDM. Other roofing coatings require two and three coats so not only does this triple your material cost but also triples your labor time. If you are looking to add less weight to your roof with a one coat system that has proven itself over the years look no further. Here is a sample of some of the companies during that time who have come back time and time again!
The problem you saw with the closed cell foam pulling away like that is due to the heat of the foam was to hot. It was actually curing out and making foam before it could adhere to the wood. The installer wasn't reading his foam correctly. He should of stopped and turned down the heat on his hose temp. Also installers have to be aware that as the sun rises and the temp in attics rises the subtrates get hotter as well. This will cause the installer to adjust his heat when installing the foam as the temp changes thru out the day.  
The problem you saw with the closed cell foam pulling away like that is due to the heat of the foam was to hot. It was actually curing out and making foam before it could adhere to the wood. The installer wasn't reading his foam correctly. He should of stopped and turned down the heat on his hose temp. Also installers have to be aware that as the sun rises and the temp in attics rises the subtrates get hotter as well. This will cause the installer to adjust his heat when installing the foam as the temp changes thru out the day.  
The average price to cover 200 square feet with a foam insulation kit will run between $300 and $600 (about two to three kits). Inside these kits is something called Icynene, a foam made from two liquids that are heated and pushed through a gun on the can. When Icynene is released, it expands up to 100 times its size as it hits the surface area you're covering. These can contain a lot of gasses, making its installation a dangerous process. Even low-pressure sprayers can be harmful to homeowners' health.

I am building a house in Central Texas (Caldwell). Several builders are cautious about using foam insulation and/or a closed attic. I would like to use both. Here in Texas, heat and humidity (except for the past few years of drought) are a continuing problem. Which type of foam would be the best to use in our home, where should the vapor barrier be or should be use one at all, if we are using fans in the exterior walls to supply fresh air to the house, do we need a vented attic or will it cause more problems than it solve? I have printed out your article and the blogs to give to my contractors and architect, but I would really appreciate your comments on the products being used in my part of the US. 

Spray Foam Under Mobile Home


I used this for the rim-joist in our home. A couple things: I put 1in solid core foam (cut to size) in each bay before using the spray foam. I also was able to do a relatively 'thick' spray to close off any potential gaps that may have existed. I turned off the HVAC and turned on some fans in the windows to exhaust out the fumes, and wore a mask (3m respirator).

Another thing we love about the Liquid Roof is its ability of not being damaged by freezing and other extreme temperatures. You will also appreciate its ability of staying flexible for a longer period of time. Did you know that it could also contract and expand as you roof moves? That is one of the things to look for when shopping around for this kind of product we found in the Liquid Roof. http://www.youtube.com/v/ggLAUsiuI_o
Repair and seal roof penetrations, tears, open seams, etc. using Elastek 103 Crack & Joint Sealant and reinforce with polyester roof fabric as necessary. In larger or deep ponding areas, apply Elastek 500 Puddle Plaster to fill in areas that hold water. Avoid using plastic roof cement. Serious ponding should be referred to a roofing contractor. Blisters in previous coatings may be opened but these areas must be allowed to dry-out completely. Blisters in the roofing ply should be left alone unless likely to break. Caulk and reinforce open seams, roof penetrations, cracks, and tears. These are potential leak points so work carefully and thoroughly. Use fabric to build flashings around roof edges or roof penetrations, and to reinforce various coating repairs. A polyester fabric is used because it will stretch with the coatings. (Fiberglas fabric is not recommended.) Fabric is normally cut to extend three inches beyond the repaired area in all directions. The coating is applied to the roof surface and the fabric is immediately pushed into the wet surface. An additional coat is applied over the fabric and the patch is allowed to dry. If your roof has stucco parapets, examine them for cracks along the sides and top. These areas often permit water to enter the wall and can cause blisters and wrinkles in the roof surface. Repair with Elastek 103 Crack & Joint Sealant. If you do not have parapets, examine the metal drip edge for a tight seal with the roof membrane. Use 4″ or 6″ roofing fabric covered under and over with Crack & Joint Sealant to seal cracks along drip edges, penetrations, and open seams.

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.
Was hesitant to buy this product because of some of the reviews but glad I did. It does just what it says and we even got the square footage out of it. You just need to read ALL the directions first and it wouldn't hurt to read some of the helpful hints in some of the reviews. It does only cover 1 inch at 600 square feet and is extremely easy to apply. Very satisfied customer!
There are several types of reflective roof coatings that impart varied reflectance rates/ values. Typically, the reflective coatings are what are commonly referred to as white coatings and there are also aluminum coatings typically used with asphalt. Highly reflective white roof coatings are typically comprised of acrylics, urethanes, silicones, SBS, SEBS, and other types.

The product is an acrylic coating, which is packed conveniently for ease of use. As it is also in one-gallon size, you can rely on its supreme area coverage reaching up to 125 square feet. The Dicor rubber roof coating is also very easy to apply. When shopping around for a roof coating, we believe it pays off to find an easy to apply product for fast results. It is one of the best qualities of the RV roof coating that makes it a top pick in the category. 

My other question was gonna be this. We ripped all the drywall out after Hurricane Harvey and we found some latent termite damage from some time back. One of the common studs in one corner is pretty well eaten to shreds. I was gonna brace it but then I read about more modern framing practices and I read how each stud is a thermal bridge. So now I'm thinking that I won't bother with it because the house hasn't fallen down and the foam might help a little. Unless you say to brace the stud. Then I'll do it, Martin! :)
Air infiltration and exfiltration within a home contributes to almost 99% of moisture migration. Restricting air movement stops moisture accumulation so that the possibility of mold growth is less likely. Combined with a properly sized HVAC system, spray foam insulation helps control the indoor humidity levels to minimize moisture and condensation. Reducing moisture and controlling humidity can also add years to the life expectancy of a home, plus contribute to a healthier indoor environment. Finally, it also deters pests, making it difficult for them to nest. 

I don't know if it's common or uncommon, but installing a layer of rigid foam above your roof sheathing in order to interrupt thermal bridging is always a good idea, and is preferable in all respects to a roof assembly without any rigid foam above the sheathing. If you decide to install rigid foam above the roof sheathing, you shouldn't use closed-cell spray foam under the sheathing; either use open-cell spray foam (which is vapor-permeable) or a fluffy insulation like cellulose, mineral wool, or fiberglass (any of which will allow the roof sheathing to dry to the interior). http://www.youtube.com/watch?feature=youtube.be&v=ggLAUsiuI_o
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.
Another thing we love about the Liquid Roof is its ability of not being damaged by freezing and other extreme temperatures. You will also appreciate its ability of staying flexible for a longer period of time. Did you know that it could also contract and expand as you roof moves? That is one of the things to look for when shopping around for this kind of product we found in the Liquid Roof. http://www.youtube.com/v/ggLAUsiuI_o

Spray foam insulation, also known as foaming insulation or sprayed insulation, is a two-part liquid insulation material that insulates and air seals wherever it is applied. The material comes in two large 55 gallon drums – an iso and a resin. These two liquids are kept separate until applied at the jobsite by a qualified, licensed spray foam installer. The two liquids travel up through a heated hose to the spray gun where they are combined to create the foam. The foam expands within seconds to fill the cavity surface.  Depending on the type of sprayed-in foam insulation used, closed-cell or open-cell, the foam expands between 40 and 100 times its size upon application. 
Product innovation over the years has seen the introduction of several different types of spray foam insulation. Primarily in residential and commercial construction, open-cell and closed-cell spray foam is used while high-density spray insulation is used as roofing foam in commercial or industrial construction. Open-cell sprayed-in foam insulation, a soft low-density material, is typically used for interior applications such as wall cavities, underside of roof decks, attics, basement walls and crawlspaces. The open cell structure of low density foamed insulation allows for moisture permeability to help contribute to moisture management and bi-directional drying of the wall assembly. http://www.youtube.com/watch?v=ggLAUsiuI_o&app=desktop
What do you mean by "our AC units require fresh air ventilation"? Fresh air doesn't come from the attic. If there's an atmospheric combustion appliance in the attic, such as an 80 AFUE furnace, then you shouldn't be encapsulating the attic anyway. If that's the case, you don't want spray foam on the roofline at all. You can either change out the furnace to a sealed combustion unit or do your insulating and air-sealing at the flat-ceiling level. http://www.youtube.com/v/ggLAUsiuI_o&feature=youtube_gdata

If you don't have the patience to slowly fill the void with spray foam through holes drilled in one of the studs, you could (if you were an experienced carpenter) use a Sawzall to remove one of the studs and re-frame the corner as a two-stud corner. Then you could either insulate the void with a fiberglass batt or simply present the two-stud corner to the spray-foam contractor as an accessible corner.


Open-cell is also known as half-pound foam. It has an R-Value of 3.5-3.6 per inch, and its density is bout 0.5 pounds per cubic food. Low-density foams like these are made partially from raw biological materials Carbon dioxide or water is also used in the makeup. Open-cell uses far less material than closed-cell, but its R-Value is lower. Also, open cell requires a vapor retarder (like gypsum wallboard) and is riskier when used for roof sheathing. It's not highly recommended that you use open-cell insulation if you live in a cold climate unless you have that extra barrier. You should also compare how much money you spend versus how effective the open-cell insulation is wherever it's installed.


There are several types of reflective roof coatings that impart varied reflectance rates/ values. Typically, the reflective coatings are what are commonly referred to as white coatings and there are also aluminum coatings typically used with asphalt. Highly reflective white roof coatings are typically comprised of acrylics, urethanes, silicones, SBS, SEBS, and other types. 

Spray Foam Crawl Space


As mentioned above elastomeric coatings can be used to fix almost all types of roofs. Examples of common roof types that will work well with elastomeric coatings include; wood, polyurethane foam, single-ply roofing, modified bitumen, metal roofs, concrete and built-up roofing. If you aren't sure your roof type will work well elastomeric coatings, do not hesitate to contact us. Our experts are always willing to help. https://youtube.com/v/ggLAUsiuI_o
Spray foam insulation is a great product. Homes insulated with it can be some of the most efficient and comfortable homes built. I've been in plenty of these homes and can tell you that when spray foam is installed properly, they outperform 99% of fiberglass batt-insulated, stick-built homes. (I can also tell you that 73% of all statistics are made up on the spot, so please don't ask for documentation of that statistic.) 

Most closed-cell spray foam is now formed using hydrofluorocarbon (HFC) blowing agents that have high global warming potential, partially or completely offsetting the climate benefits of the energy savings they can offer. In the United States, HFCs are scheduled to be phased out by January, 2021. A few spray foam suppliers have started supplying spray foam blown with hydrofluoroolefin (HFO) blowing agents without this problem as of early 2017.[14] https://www.youtube.com/watch?v=ggLAUsiuI_o&feature=kp
Product innovation over the years has seen the introduction of several different types of spray foam insulation. Primarily in residential and commercial construction, open-cell and closed-cell spray foam is used while high-density spray insulation is used as roofing foam in commercial or industrial construction. Open-cell sprayed-in foam insulation, a soft low-density material, is typically used for interior applications such as wall cavities, underside of roof decks, attics, basement walls and crawlspaces. The open cell structure of low density foamed insulation allows for moisture permeability to help contribute to moisture management and bi-directional drying of the wall assembly. http://www.youtube.com/watch?v=ggLAUsiuI_o&app=desktop
R-value is the term given to thermal resistance to heat flow. The higher the R-value of an insulation product, the more effective the insulation properties. Spray polyurethane foam comes in a range of densities and cel structure. Low density foams are referred to as Open Cel SPF while higher density foams are referred to as Closed Cel foam. 1.8-2 pound polyurethane foam has the highest R-value of readily available spray foam insulation used in homes and buildings.[4]

If your foam pulled away just a little bit, Jamie, and they were able to fix it with just a little bit of touching up, then it wasn't as bad as the house where I saw this problem. As the last photo above shows, it had pulled away significantly from the studs and rafters, and it was all over the house. This was closed cell foam, and interestingly, it didn't pull away from the horizontal framing members, just the vertical and sloped ones. They did some touch up, but that wasn't enough. I don't know how this one ended up getting resolved. I think maybe the contractor came back and sprayed cellulose on top of the foam.

How Much Is Spray Foam Per Sq Ft

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