• Insulation materials often differ in terms of their thermal resistance/R-value, cost, environmental impact, and application.
• Consumers now have access to a wide variety of different insulation materials.
There are a wide variety of insulation materials available, ranging from the main fiber materials like rock, slag wool, fiber glass, and cellulose and from natural fibers to sleek foils and rigid foam boards. The more bulky materials have the ability to resist both conductive and convective heat flow, to a lesser extent, in building cavities. By contrast, conductive heat flow is resisted by rigid foam boards by trapping air and gas. In addition, reflective foils and insulation work by reflecting radiant heat outwards from living areas, which make them quite useful in cool climates. There are also other materials available that are less common such as vermiculite and perlite and cementitious and phenolic foams.
Fiberglass consists of very tiny glass fibers and is a commonly used insulation material. Most commonly, it is used for two types of insulation: batts and rolls (blanket) and loose-fill but it’s also found as duct insulation and rigid board.
Fiberglass batt insulation products are now manufactured in a range of densities from low and medium to high-density, which have R-values slightly higher than standard batts. Denser fiberglass products are typically used for insulating spaces that have limited cavities—cathedral ceilings, for instance.
To put this into perspective, high-density batts for a stud-framed wall of 2 by 4 inches would have an R-value of 15 as compared to R-11 for a low-density batt. For the same space, a batt of medium-density offers a value of R-13. A high-density batt for a frame wall of 2 by 6 inches offers R-21 and R-30 for 8.5-inch spaces. R-38 batts for a 12-inch space can also be purchased.
There is an unconventional insulation product that fuses together two different forms of glass. The two glass types form curls at random when they are cooled during manufacturing. This material can be less aggravating and, by extension, more safe to work with. In addition, the batts do not require chemical binders to hold them together and handling is assisted by a perforated plastic sleeve.
Loose-fill fiberglass insulation is created using molten glass which is blown or spun into fibers. Manufacturers often use recycled glass totaling 20% to 30% for its production. However, it can only be applied when using a blowing machine either in open-blow or closed-cavity spaces. You may want to learn more about where to insulate.
A variation on loose-fill is a system known as the Blow-In-Blanket System® (BIBS). This insulation is installed dry and has been proven to insulate walls much better than other types of fiberglass insulation, including batts. The later hybrid system, BIBS HP, combines this with sprayed polyurethane foam.