Definitions for **"R value"**

A measure of insulation, or more specifically, a measure of a material's resistance to the passage of heat; the higher the R value, the better it insulates (e.g., the walls of a typical new home are usually insulated with 4" of batt insulation with an R value of R-13, and a ceiling insulation of R-30)

This measures a materials resistance to the ability of heat to flow through it. A high number here is superior. To read more on R Value.

A measure of the overall resistance to heat transmission due only to the difference in air temperature on either side of the material.

a value given to insulation. The higher the 'R' value, the slower the rate of heat loss.

a number indicating how much resistance insulation presents to heat flowing through it

Property of an insulation material used to characterize the effectiveness of the insulation in reducing heat transfer by conduction. The higher the "R" value, the better the insulation’s ability to reduce this heat transfer.

A measurement of the ability of insulation to slow the transfer of heat or cold. The higher the R value, the greater the insulation power.

"R" stands for resistance to winter heat loss and summer heat gain and is more accurate than inches in designating insulation performance. Even though one type or brand of insulation is thicker or thinner than another, it will provide identical resistance to heat loss if the R-value is the same. R-values can also be added. If you now have R-11 attic insulation and you want R-30, you can add an insulation material rated at R-19.

Insulation is rated in terms of thermal resistance, called R-value, which indicates the resistance to heat flow. The higher the R-value, the greater the insulating effectiveness. The R-value of thermal insulation depends on the type of material, its thickness, and density. In calculating the R-value of a multi-layered installation, the R-values of the individual layers are added.

A measurement of resistance to heat loss in building materials. R-Value is the reciprocal of U value (1 divided by U-Value = R-Value) Resistance to thermal transfer or heat flow. Higher R-Value numbers indicate greater insulating value. R-Value is frequently used in the insulation industry and is the reciprocal of U-Value, which is more commonly used in the window industry.

A measure of insulationâ€™s resistance to heat flow. The higher the R value, the more effective the insulation.

Standard insulation value. One "R"value equals one inch of wood. Normal straw is R 45 to 50.

a measure of the heat conductivity of material. The higher the R value, the better the material serves as insulation from heat transfer.

Resistance Value. The measurement of the capacity of a material to resist heat loss. The higher the number, the lower the heat loss.

A measure of insulation. A measure of a material's resistance to the passage of heat. The higher the R value, the more insulating "power" it has. For example, typical new home's walls are usually insulated with 4" of batt insulation with an R value of R-13, and a ceiling insulation of R-30.

Resistance to heat transfer of material.

A measure of resistance to heat gain or loss (insulative ability). "R" Values rather than thicknesses can be compared for different materials, since 6" (152mm) of fiberglass (R-19 [R-34]) might compare with 12" (305mm) of wood or 18' (15.5m) of stone. "R" value of some common substances of 1" (25mm) thickness: Concrete 0.1 (0.018) Stucco and Brick 1.2 (0.21) Plywood 0.1 (0.18) Fiberglass batts (0.54) Concrete 0.1 (0.018) Polystyrene 6.25 (1.10) Polyurethane foam 7.7 (1.36)

A method of measuring the insulation capabilities of materials.

A measure of insulation. For example, typical new home's walls are usually insulated with 6" of bat insulation with an R value of R-19, and a ceiling insulation of R-28.

The measurement referring to the resistance to heat flow in insulation. The higher the "R" value, the more effective the insulation.

Standard insulation value which measures the esistance in a material to the passage of heat. An R-value is the inverse of a U-value which measures the conductance in a material of heat.

A measure of insulation value. The higher the R value, the more insulating effect it has.