Knowing an insulation’s R-value is a key part of designing an effective mechanical insulation system. It is one of the factors insulation installers use to help determine if a material is right for a job. But what exactly does this number mean and how does it impact thermal transfer? This week we are going to take an in-depth look at R-values and why they are so important.
Thermal Resistance
When it comes to industrial and commercial applications in the Great White North, insulation needs to contend with our extreme temperatures. That means keeping the heat inside in the winter and the heat outside in the summer. R-value is the measure of thermal resistance. In plain terms, how effective is the material at preventing conductive heat transfer. The larger the number, the more the thermal resistance. This value is calculated by measuring the heat flow across a surface where each side is at a different temperature.
Conductivity
As we mentioned before, R-value refers to how a material handles conductive heat transfer. This type of thermal travel is what occurs when substances are in direct contact with each other. For example, a frying pan is directly heated by the stove’s hot burner. When hot air warms up the outside of a building, that heat will naturally travel inwards and subsequently warm up each substance it comes into contact with. Properly installed insulation will slow down or stop this process before the heat can transfer to the next surface. The same goes for when the inside of a building needs to be kept warm and the outside is cool. Insulation high in R-value works to keep that heat inside.
Beyond R-Value
As you may expect, R-value is a useful number when determining the efficiency of insulation. With that in mind, there are a number of factors that will affect the actual R-value once installed. Improper installation and thermal bridging are just two of these that will drastically reduce a material’s thermal resistance. Beyond this, heat travels through convection and radiation as well as conduction. These are not measured by R-value. Because of this, R-value should not be the only deciding factor when choosing insulation materials.
R-value is a great tool for insulation experts and industry leaders to determine the thermal resistance of a material. With that in mind, it should be considered alongside other metrics during the design phase of a mechanical insulation system. If you’re looking for superior insulation installation in the Calgary area, contact the experts at Westcal Insulation today!
