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.

Spray Foam Under House


As mentioned above, These coatings can work with almost any roof type. Another advantage is they are long-lasting. The coatings are resistant to fungi and mildew among other common materials that damage roofs with time. Another advantage of the coatings is that they are seamless, providing a neat uniform coating. Elastomeric coatings offer individual benefits to certain roof types. For instance, polyurethane foam roofing benefits greatly from the coatings by getting great ozone and UV light protection. The heat reflexive properties also offer great benefits such as lowering cooling costs. This advantage is enjoyed regardless of the rooftype. The heat reflexive properties also offer anti-aging properties when coatings reflect harsh sun rays which age roofs with time. Elastomeric roof coatings are also simple to use, VOC compliant and nontoxic.


Excellent kit for insulating a house. Slow rising foam takes longer to insulate an area as you must do it in layers 1" thick. Any thicker can overheat the chemicals and prevent a proper cure and off-gassing. Recommend purchasing a second suit and nozzles so you can use it multiple days to achieve the thickness desired for the highest R value. Seals up and insulates much better than traditional fiberglass. The sound suppression is noticeably different. Used it to insulate the ceiling above our bedroom. The sound is remarkably more quiet than the fiberglass insulation we had before. The only down side is the weight of the containers. Using a smaller kit would be easier to handle and move around when spraying a ceiling in an attic. A word of caution, use plywood that spans at least 2 joist per container when spraying in an attic to hold the weight.

How Much Is Spray Foam Roofing


Sealection 500 is a spray-applied adhesive, which once applied, expands in place using water-blown technology, without CFCs, HCFCs, or ozone-depleting chemicals. Unlike traditional fiberglass insulation, Sealection 500 will maintain its performance; time and temperature have no effect on the spray foam insulation's R-value of 3.81 at 1 inch. Sealection 500 never deteriorates or decomposes. The product retains its shape and half-pound density over time, and never settles or compacts.

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). https://youtube.com/watch?v=ggLAUsiuI_o&app=desktop
Sealection 500 is a spray-applied adhesive, which once applied, expands in place using water-blown technology, without CFCs, HCFCs, or ozone-depleting chemicals. Unlike traditional fiberglass insulation, Sealection 500 will maintain its performance; time and temperature have no effect on the spray foam insulation's R-value of 3.81 at 1 inch. Sealection 500 never deteriorates or decomposes. The product retains its shape and half-pound density over time, and never settles or compacts.
Starting a new build (1 1/2 basement walkout), all 2x6 exterior walls w/ brick veneer in CZ3. Above grade, would like to do spray foam in 2x6 walls, 1/2" or 1" of rigid foam board on the exterior, and a 1" air gap. Will this require a house wrap or can I do w/o the rigid foam and go with a housewrap? Also, any recommendations about insulation strategies for the finished basement. Thanks!

Roof Coating

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