Blown-in cellulose insulation and polyurethane foam insulation flow around obstructions well, making it easy to fill walls with insulation without tearing down the walls. Both cellulose and polyurethane foam insulation are very effective thermal insulators and provide similar insulation values to traditional rolled fiberglass.
Cellulose insulation is comprised of loose, shredded newspaper that has been combined with certain chemicals. The function of the chemicals is to make the insulation fire retardant. Foam insulation is made out of polyurethane foam that expands quickly after application. Polyurethane foam insulation is made out of completely synthetic materials while cellulose insulation can contain upward of 75 percent recycled materials.
Cellulose Insulation typically offers R-values in the 3.0 to 3.5 per inch range. Polyurethane foam insulation offers R-values in the 3.5 to 4.5 per inch range but can reach as high as 8 per inch, depending on the brand. Polyurethane foam insulation can lose R-value over the years as the material slightly degrades.
Polyurethane foam insulation is dangerous to handle. Gloves should be worn while installing or handling this type of insulation. Eye exposure can lead to temporary blindness. Consumers should also wear protective goggles and respirators while installing or handling polyurethane foam insulation.