Arguably, the most important characteristic of any insulation is its ability to significantly reduce, or altogether stop, heat transfer. This is known as thermal resistance. The opposite of this is thermal conductivity. These two qualities are key in determining the r-value of a material. In this week’s article, we are going to discuss how resistance and conductivity are calculated, and how professional installers use these numbers to design an effective insulation strategy in industrial or commercial applications.
Thermal Conductivity
In the same way as electrical conductivity, this thermal property describes the amount of heat a material will let transfer through it in a given amount of time. More specifically, a unit temperature gradient that is perpendicular to the unit of a homogenous material in question. The most important factor in this type of equation, other than the material itself, is the thickness of said material. The thicker the material, the lower the conductivity. The final number derived from this equation is known as the k-factor.
Thermal Resistance
This property is calculated by using the k-factor, thermal conductivity, and the thickness of the material. The resulting number is known as the r-value. For many, this value is the first indicator of an insulation material’s effectiveness. Because r-value varies by thickness, however, it is important to ensure you have enough material to meet the requirements of a specific area. For example, let’s say you have a loose-fill fibreglass insulation with an r-value of 2.0 and the recommended r-value for a specific area is between 6.0 and 7.0. You will need to install at least 3 inches of the fibreglass insulation for it to meet the minimum requirements.
Using the Right Insulation for the Job
Different areas in a facility will need different r-values. Certified professionals will have a working knowledge of which areas need more thermal resistance than others. In our northern climate, our industrial and commercial buildings typically need to prepare for more extreme temperatures than the more moderate South. Furthermore, it’s worth it to know that the r-value stated on the packaging has been calculated in ideal conditions. This means that ageing, temperature, and moisture will all affect the actual performance of said insulation.
Thermal resistance and conductivity are two important factors in determining the effectiveness of an insulation, but they are by no means the only considerations. Think of r-value as a jumping-off point for insulation experts to build from. For those who run their own business or own facilities in Alberta, find out how thermal resistance through mechanical insulation can benefit you by requesting a quote with our experts today!
