Convert Thermal Conductivity

Thermal conductivity is a material property that describes how well a material conducts heat. It's measured as the rate of heat transfer through a unit thickness of material per unit area per unit temperature difference. Materials with high thermal conductivity (like metals) transfer heat quickly, while low conductivity materials (like insulation) resist heat transfer.

W/(m⋅K) stands for watts per meter-kelvin. It represents the amount of heat (in watts) that flows through one meter of material thickness across one square meter of area when there's a temperature difference of one kelvin (or degree Celsius) between the two sides.

Lower thermal conductivity values indicate better insulation. Good building insulation typically has values below 0.1 W/(m⋅K). For example: fiberglass insulation ~0.04 W/(m⋅K), foam insulation ~0.03 W/(m⋅K), while concrete is ~1.7 W/(m⋅K) and aluminum is ~200 W/(m⋅K).

Historical measurement systems persist in different industries and regions. The US construction industry often uses BTU⋅ft/(hr⋅ft²⋅°F), while most of the world uses the SI unit W/(m⋅K). Both measure the same physical property but with different scaling factors.

Thermal conductivity measures how well a material conducts heat (higher values = better conduction), while thermal resistance measures how well it resists heat flow (higher values = better insulation). They're inversely related: materials with high thermal conductivity have low thermal resistance.

Thermal conductivity varies with temperature for most materials. Metals generally decrease in conductivity as temperature increases, while gases and many insulating materials increase. This is why thermal conductivity values are often specified at standard temperatures (usually 20°C or 68°F).