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?

When it comes to insulating the house, fiberglass tends to be the common form of insulation. However, after comparing fiberglass and spray foam insulation, it’s shocking how fiberglass tends to be the lesser of the two. Although it has deemed reliable over the years, there are way more benefits to insulating your home with spray foam. One of those benefits includes regulating the temperature of your house.


You’ll quickly recover your investment in a new spray foam insulation system. Your productivity will soar at the same time you’re spending less on material costs and overall operating costs. And by giving your customers the benefits of polyurethane spray foam over traditional, inefficient fiberglass, they can expect higher resale values from their properties and significantly lower utility costs. Using spray foam to minimize air leaks in walls and roofs, a typical homeowner could save up to 15% on heating and cooling costs, according to the U.S. Department of Energy.
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. 
We love the Heng’s rubber roof coating because it is versatile enough to work on the RV roof and protects it from the elements longer than other products do. Plus, it is useful enough to be used in sealing seams and tears. Versatility does matter when shopping around for an RV roof coating. It ensures more uses, meaning more value for the money. That said we don’t need to buy a separate product to perform the tasks. https://www.youtube.com/watch?v=ggLAUsiuI_o&feature=youtube_gdata
Spray foam is available in two different types: open-cell spray foam which is usually $0.44 to $0.65 per board foot and closed-cell spray foam which is about $1 to $1.50 per board foot. The average cost to have spray foam professionally installed is about $2,314. This number can vary depending on whether the home being insulated is newly constructed. However, finished homes are not a good candidate for spray foam insulation but great for weatherization or an energy audit.  
Roof coatings can add 25 years to the service life of a roof and reduce the amount of discarded roofing materials that end up in landfills. The infrared image on the right shows 175 °F (79 °C) on the uncoated (black) section of the modified bitumen roof. The coated (white) section is 79 °F (26 °C). Field studies have shown that cool roof coatings can lower rooftop temperatures and reduce air conditioning bills.

Allison--would be very interested in your take on the GHG issues of foams, which have received lots of smart commentary recently. To highlight a few: architect Jesse Thompson's comments on Tom's Good vs Bad post on Energy Circle, the very thorough piece by Alex Wilson on Green Building Advisor and Michael Anschel's cautionary diatribe on Remodeling.  https://www.youtube.com/watch?v=ggLAUsiuI_o&feature=share
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.
Spray foam insulation, like other insulation, saves on energy costs and lowers utility bills. Studies by the US Department of Energy show that 40% of a home's energy is lost as the result of air infiltration through walls, windows and doorways. Buildings treated with spray foam insulation insulate as much as 50% better than traditional insulation products.
Warning: EnergyGuard™ Elastomeric Roof Coatings can freeze below 32° F. This is because the product is water based. In case of freezing temperatures, stop the application process. After application, you must allow the product time to dry before exposing the elastomeric roof coating to foot traffic or water. You should also cover the containers and dispose them responsibly after application. In case you or someone else i.e. a child ingests the coating seek immediate medical attention. Don't induce vomiting.

Spray foam can also contribute to more comfortable interior spaces and less costly monthly energy bills. The U.S. Environmental Protection Agency estimates homeowners can save an average of 15 percent on heating and cooling costs by air sealing their homes and adding insulation in attics, floors over crawl spaces, and accessible basement rim joints. 
Spray foam insulation helps lower utility costs because it blocks heat and cold from the outdoors. Recent studies by the U.S. Department of Energy state that around 40 percent of all energy is lost through poor insulation. Spray foam insulation is able to insulate homes at least 50 percent more than traditional insulation products. Spray foam insulation can also provide protection against moisture, which otherwise leads to the unwanted development of mold and mildew. And it can also be used for noise reduction as well. In fact, spray foam is good for homes and buildings in which outdoor noise can be a distraction.
In general, cantilevered steel beams are a nightmare. If part of the steel beam is in contact with exterior temperatures, then it's best if the interior portion of the steel beam is covered on all sides with insulation. This is generally impossible (because the interior portion of the cantilevered beam generally supports a load, meaning that you can't wrap the steel beam in insulation on all sides). http://youtu.be/ggLAUsiuI_o
Spray foam insulation works by sealing the building envelope to stop conditioned air from escaping and prevent unwanted outside air from entering your home. It allows efficient use of your HVAC system and helps regulate the temperature fluctuations and humidity in your home. It's a lightweight, durable, and versatile insulation solution boasting the industry’s strongest performance in energy efficiency and energy cost savings.
Builders often turn to high-density SPF when high insulation values and strength are needed. As its name implies, this foam has a denser structure than either of the other SPF types. Therefore, it does not expand as much as lower density foams and requires more material to cover and insulate any given space. This spray foam is often an excellent choice for roofing or other exterior insulation because of its seamless, monolithic nature. High-density SPF can also help reduce energy costs significantly over a roof’s lifetime due to its thermal resistance properties. It also offers increased protection against air and water infiltration and strengthens the structure to which it is applied. The bond that SPF forms to the roof can increase a building’s resistance to wind uplift, which can help reduce damage experienced during periods of high wind.
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.
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.

To see if ShippingPass is right for you, try a 30-day free trial. Also, with ShippingPass, there is no need to worry about commitment. If you decide you want to discontinue the service, you can cancel your subscription at any time. No matter what your shipping needs, Walmart's got you covered. Sign up for ShippingPass so you can shop more, save money and live better.


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.
While coatings may potentially stop minor leaks, the roof should be properly repaired and dried prior to coating application. Coatings may be able to seal pinhole leaks, which are leaks not visible to the naked eye. If the roof is leaking, the roof leak will need to be identified and repaired prior to any recoating; do not expect the coating to find and seal the leaks.
You are eligible for a full refund if no ShippingPass-eligible orders have been placed. You cannot receive a refund if you have placed a ShippingPass-eligible order. In this case, the Customer Care team will remove your account from auto-renewal to ensure you are not charged for an additional year and you can continue to use the subscription until the end of your subscription term.

I started using Gaco years ago primarily to solve ponding water Problem. It has work well, solved my problems with other roofing options and repairs as well as many other Flat roof issues.  My only problems were experienced when I did not clean the surface well enough for good adhesion.  Follow the Instructions.  Great product and highly recommended. .

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. http://m.youtube.com/watch?feature=player_embedded&v=ggLAUsiuI_o
A well-insulated and sealed building envelope can significantly contribute to optimal energy efficiency. As with any project, to fully utilize the benefits of spray foam, attention to detail and proper installation is crucial. It’s important to take appropriate time or seek aid through outside expertise to understand how all types of insulation products can work together within the construction of a home or building and the surrounding environment. When installed correctly, spray foam has the potential to be one of the most effective choices for insulation solutions. http://m.youtu.be/ggLAUsiuI_o
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.

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.
OK, Peter, I finally went back and read Alex Wilson's article on what he perceives as a serious problem. I haven't seen the full report, but based on the summary he wrote on the Green Building Advisor website, I question the science. It seems to me that he's chosen the wrong metric and he's basing his conclusion on too many assumptions because he doesn't have enough data. You can see my comments at the end of his article. http://www.youtube.com/watch?v=ggLAUsiuI_o

Due to its relatively large cell structure, low-density foam stays somewhat soft and flexible after curing. This increases the likelihood of its continuing to provide high insulation value even as the building settles and shifts over time. Low-density SPF provides heat insulation and seals airflow through cracks, joints and seams by filling the cavities. In addition, this foam can help absorb sound thanks to its soft texture and open-cell structure.
Spray polyurethan foam does effectly prevent all six of these heat transfer methods from occurring. These should be the mechanisms by which you judge insulation, in addition to their R-Value. If you're uncertain about installing spray foam insulation, Energy Star has a map that recommends levels of insulation by R-value and cost-effectiveness in the United States.
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 https://youtu.be/ggLAUsiuI_o
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.
We live in middle TN and had our house foamed last year. We noticed recently that some of the foam was shrinking and seperating from the floor joists. We contacted the installer and he informed us that the manufacturer had a problem with a batch of foam during the time frame we had our house sprayed. The contractor wasn't sure if we had the recalled batch installed in our house or not. He said he would check the batch numbers and let us know. He seems like a nice guy promising to do whatever it takes to fix any problems. Do we trust him, however, to be truthful about the batch number? Do we have any options for finding out the information ourselves? I inspected the entire crawl space of the house and noticed approximately (5) areas that were seperating and a couple areas where the foam didn't adhere to the block. Do I assume by it being so infrequent that it is nothing to be concerned about? My concern is the walls that are not capable of being visually inspected because of sheetrock.

How Much More Expensive Is Spray Foam


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]

How Much Is A Board Foot Of Spray Foam

×