0.07 W Mk in R Value Insulation Calculator

This calculator helps you convert a thermal conductivity value of 0.07 W/m²K to R-value, which is a key measure of insulation performance. Learn how to interpret R-value, understand its importance in building insulation, and use this tool to make informed decisions about your home's energy efficiency.

What is R-value?

R-value (also known as thermal resistance) measures how well a material resists heat flow. It's expressed in units of m²·K/W (square meters-kelvin per watt) or ft²·°F·h/Btu (square feet-degree Fahrenheit-hour per British thermal unit) in the US.

The higher the R-value, the better the insulation. For example, fiberglass insulation typically has an R-value of around 3.8 to 4.0 per inch, while foam board insulation can reach 6.0 or higher.

Key Point: R-value is different from U-value (thermal transmittance), which measures how easily heat passes through a material. Lower U-values indicate better insulation.

Converting 0.07 W/m²K to R-value

The thermal conductivity value of 0.07 W/m²K can be converted to R-value using the following formula:

R-value = Thickness / Thermal Conductivity

Where:

R-value is in m²·K/W
Thickness is in meters
Thermal Conductivity is in W/m·K

For example, if you have a 10 cm (0.1 meters) thick material with a thermal conductivity of 0.07 W/m·K:

R-value = 0.1 m / 0.07 W/m·K = 1.43 m²·K/W

This means the material provides 1.43 m²·K/W of thermal resistance per meter of thickness.

How to use this calculator

Enter the thickness of your insulation material in meters or inches
Select the appropriate unit system (metric or imperial)
Click "Calculate" to see the R-value result
Review the detailed explanation of the calculation

The calculator will show you the R-value for your specific material thickness, helping you compare different insulation options.

Common insulation materials

Here's a comparison of typical R-values for common insulation materials:

Material	R-value per inch	Typical Thickness
Fiberglass	3.8-4.0	1-2 inches
Cellulose	3.5-3.8	3-6 inches
Mineral Wool	3.0-3.5	2-4 inches
Polyiso Foam	6.0-7.0	1-2 inches
XPS Foam	5.0-5.5	1-2 inches

Note: These values are approximate and can vary based on installation conditions and manufacturer specifications.

FAQ

What is the difference between R-value and U-value?

R-value measures how well a material resists heat flow, while U-value measures how easily heat passes through. Lower U-values indicate better insulation. The relationship is U = 1/R.

How do I choose the right insulation thickness?

The required thickness depends on your climate, building code requirements, and desired energy efficiency level. Consult with a professional or use our insulation thickness calculator for guidance.

Is higher R-value always better?

Higher R-value is generally better for insulation, but you should also consider cost, installation difficulty, and other factors. Thicker insulation may not always be the most practical solution.