Blown-In Insulation: R Value Explained
When choosing a type of insulation, learning about the specific advantages and disadvantages of blown in insulation is a good idea. In particular, it is important to learn about R-value, which is a method of measuring the strength of any type of insulation. Knowing the R-value of an insulation material will let you know about its effectiveness, as well as helping you to decide how much of it you need. What follows should give you a good understanding of R-value, as well as how it relates to the various types of loose fill insulation.
What is R-Value?
R-Value is a number that describes the effectiveness of a particular insulation material. Describing insulation materials in terms of their R-Value allows a quick, simple comparison of how well they will prevent heat from entering and leaving your home.
Strictly defined, the R-Value of any particular insulation material is the amount of heat that can be transferred through a specific amount of space taken up by that material. The particular units, and therefore the R-Value numbers themselves, vary depending on location. In the United States, R-Value is usually measured in Fahrenheit and feet. In contrast, most other locations use meters and kelvins. It is important to know which type of measurements are being used when comparing the R-Values of two materials, or the comparisons may become meaningless due to the different unit types used in measurement. Of course, measurements from the same source will normally use the same type of units.
Types of Blown-In Insulation
If you are looking for a material to use as loose fill insulation, you have many options to choose from. Cellulose is one type of blown-in insulation. Generally speaking, cellulose insulation is made from recycled paper and a few non-toxic chemicals to make it resistant to fire.
Another option available to you is rock wool or mineral wool insulation, which is also commonly made from recycled materials, though not always. Mineral wool can come from a variety of sources, some of which can break apart and cause health problems if inhaled. Be sure to research the particular material you choose if you pick this type of insulation.
You can also choose to use fiberglass as a blown-in insulation material. Fiberglass is an efficient insulation option, and on top of that it contains recycled glass.
Blown-In vs. Batts
In general, solid insulation tends to have a higher R-value than loose fill insulation of the same type, though sometimes the solid and loose fill versions of the same material will be comparable. However, solid insulation can be more difficult to install, so blown in insulation remains a viable option, particularly when less insulation is required, or when insulation must be added to existing walls.
Loose fill cellulose has an R-value of 3, which is more than many types, but far from the best. Fiberglass, when installed loosely, has an R-value of 2.5. When installed as solid panels, its R-value can vary from 2.5 to 3.6, depending on the particular style. Mineral wool that is blown in also has an R-value of 2.5, whereas mineral wool batts have an R-value of 3.