Understanding Rigid Insulation R Value
Rigid insulation r value is a material that is designed to be energy efficient by keeping cold and heat from penetrating walls. This has been found to be a great boon especially in areas where there are extremely hot or cold periods during the year. There are several different types of this type of board insulation.
Because of misrepresentation regarding this type of material, the US Department of Energy (DOE) has established a method of gauging its effectiveness. This method is called the R-value, which is the ability of its construction to resist heat. This value rating also connected to various buildings depending on local climate so may vary from one location to another.
The R-value is also given to types of materials that are not of solid construction such as fiberglass (3.2 per inch), which comes loose or in rolls, batts and blankets, Cellulose (3.2 per inch) which is a sprayed on material and Mineral Wool (3.1 per inch) which is blown into walls and ceilings. Rigid sheets are classed at 4.0 to 6.5 per inch.
The materials, that are used for the solid type of this weather resistant material, are polystyrene, compressed mineral wool, polyisocyanurate, polystyrene, and firm fiberglass. They repel water and can be obtained in various sizes and thicknesses. As a result, one will find a wide variety of their use in the construction industry.
Applications of this material, such as below grade foundations, under basement slabs, vinyl siding backing, basement walls, backup for walls and ceiling are quite common. It is used for many other purposes as well as in all types of construction. Builders have found that, by using the sheet type of this weather resistant material, they can use 2×4 rather than 2×6 studs which results in quite a savings when constructing a new building. In addition, this allows temperature resistance of the wall framing. In other words it stops heat or cold from the outside from producing temperature spots in the wall which is often evident where insulation does not cover the studs.
There are three types of this solid weather resistant material. They are Molded expanded polystyrene, made from liquid polymers, Extruded expanded polystyrene which is denser and Polyurethane foam board which is thin and is often used in small spaces. Although it provides excellent thermal resistance to roofs, foundations and walls, there are also a disadvantages to the foam board. Insects, such as carpenter ants and termites love it for nests and tunneling. However, rigid insulation r value provides great benefits in protecting all types of buildings from extreme heat or cold and is very energy efficient.
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