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Spray-On Closed-Cell Insulation

This NCFI polyurethane spray-on insulation sets up as a rigid product. It will be sprayed in to about 3 1/2 inches in depth and will provide an insulation value of R21. It is sprayed directly onto the back of the sheathing and sticks to it, swelling to 25 times its liquid volume. The foam itself is filled with microscopic bubbles. Since air molecules transport heat energy rapidly from the warm wall to the cold wall, the goal is to stop them or impede their movement with a web of cells inside the insulation. This insulation is also enhanced with Enovate, a Honeywell chemical that is added to the spray to create a new, slower, larger molecule that moves inefficiently to pick up and transfer heat. Heat transfer is therefore retarded in two ways, making for an extremely high insulation value. The foam comes as a two-part product, delivered as a liquid from two drums that mix the components through a sprayer. The liquid is sprayed at a very high pressure, about 2,000 pounds per square inch, to mix the chemical with the hardener and deliver it to the building cavity. More information