Spray Foam Insulation Terminology and Keywords

In the quest for insulation, any homeowner will come across foreign terms. Without knowing the industry basics and standards, how does one determine what is the good and the bad, the efficient and the inefficient, as well as figure out exactly what is best for your home or business? As industry professionals, we want to help you speak the language of insulation and help you save energy and money.

To start, Insulation is added to your home’s walls, floor and roof to keep the temperature in your house consistent. Essentially, hot air likes to flow toward cold air until the air is neutralized. This obviously happens in both the summer, when warm air tries to move inside, and in winter, when cold air tries to move out. Insulation added to a house prevents heat from moving to cooler areas which causes the interior of your house to feel uncomfortable. While being the most cost-efficient way to reduce your heating and cooling bills, insulation can also reduce future maintenance costs.

There are many types of insulation, but the most common types are traditional batts and spray foam insulation. What is spray foam? Spray polyurethane foam is a heat-activated polymer that is exactly how it sounds; a foam that is sprayed and stays in place to insulate your home. We may be a little biased, but we’re a big fan of spray foam insulation. We’ve even written a blog on how Spray Foam is Better Than Traditional Insulation (read it there!).

When it comes to spray foam, there are open-cell and closed-cell. Open-cell spray foam has a density of about 0.5 lb. per cubic foot and an R-value of 3.5 or 3.6 per inch (which we will explain later). This type of foam is relatively vapor-permeable and is made of bio-based raw materials. Open-cell foams use water primarily as the blowing agent. Closed-spray foam is a lot denser than open-cell foam, weighing in at about 2 lb. per cubic foot and an R-value of 6 to 6.5 per inch. Closed-cell foam is also a vapor retarder and uses a chemical blowing agent. Unlike open-cell foam, closed cell foam can be used on both interior and exterior surfaces – this makes it more versatile. Both open-cell and closed-cell foams have their benefits and weaknesses.

So what do things like R-value, weight and material mean for insulation? Well R-value describes how much heat can permeate a material. The higher the R-value, the less the material allows heat flow. In the US, it’s legally required that the R-value of a material is provided at the point of sale; however, R-values have different meanings in different countries, and it’s important to understand when browsing around. R-value can also change due to a varying thickness. When products are used together, the R-value will include the thickness and values of the other products including the inner and outer layers surrounding the insulation. But just because a type of insulation has the highest R-value, does not mean that’s the best insulation. Different parts of a structure (or house) require different R-values (and pressures and densities).

And after all of that information, it’s only one piece of the puzzle. The next part is the installation of the insulation; the insulation, R-value (and more) all depend on factors such as your climate, the way your house was built, your budget, what part of the house you are insulating, and more. We know a lot goes into deciding the best insulation for your needs. We are here at MPI Foam to help you with any of your Raleigh Spray Foam Insulation questions, comments, and concerns.


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