Understanding the fundamentals of insulation

Understanding the fundamentals of insulation begins with a good understanding of the fundamentals of heat transfer. There are three main types of heat flow, and when striving for energy efficiency, it’s all about controlling that heat flow. Every building structure, regardless of its size, is essentially an "envelope". And that "envelope" is constructed with building materials that will impact heat transfer, both positively and negatively. In short, everything is dependent on everything else.

CONDUCTION HEAT

Also referred to as thermal conduction, conduction heat is transferred from one solid to another. For instance, when a towel is placed on top of a hot water radiator, heat flows from the radiator (hotter) to the towel (cooler). This type of heat flow can be reduced with an insulation layer that will resist the heat transfer because of its “low thermal conductivity”. The resistance factor of the insulation is measured as R-Value, where the higher the value, the more the insulating value.

CONVECTION HEAT

In simple, general terms, convection heat is the flow of heat when heated air moves away from the heat source. The convection cycle occurs because warm air has the tendency to rise, and is replaced below it with cooler air. This cycle can be triggered when temperatures change, when humidity fluctuates, or when there is air movement. With regard to the building “envelope”, air infiltration (air leakage) is heated air or cooled air that enters and/or exits the “envelope”.

RADIATION HEAT

Radiation heat (thermal radiation) is the transfer of heat from light waves. Heat is generated when radiation is converted into heat and released into the air, or comes in contact with a nearby material. By example, a conventional light bulb radiates heat, and when touched, can be extremely hot.   When it comes to insulating, “radiation-impeding” materials like aluminum foil can greatly reduce radiating heat. “Radiant barriers” reduce radiation light waves, and consequently heat.

Choosing insulation that is most appropriate

The most common criterion for choosing insulation is R-Value. And while this is important in terms of measuring insulating value, there is much more to consider. Resistance to moisture, fire, mold, and insects should also be considered, and most importantly is the ability to inhibit air leakage. Finally, the cost of insulation materials is also important, as this will have a direct effect on larger, more extensive projects. Clearly, choosing the most appropriate insulation should include all of the above.

The primary purpose of insulating is conserving energy, and that should translate into energy cost savings. By far, the best results are achieved with spray foam insulation - a premium quality product that provides better outcomes than any other product on the market. A spray foam installation can accomplish numerous objectives in one shot: it makes a space completely airtight; it serves as an air and moisture barrier at the same time; and it insulates with higher R-Values than other products.

All things considered, insulating is a major project. Product cost, as well as installation cost, will have a direct bearing on the budget, so it’s vital to install the best, most cost-effective product or product combination.