When most people think of insulation, they think of keeping something hot or cold. For example, a thermos is insulated so that when you pour a hot drink into it, it stays hot. This is useful when people are going to a place where they will want a hot drink, but will have no way of making it, like a trip to the snow. Then there is the good old esky that keeps drinks cold on a scorching day, because it’s insulated. This article explores the fundamental concepts of insulation and implications for Australian homes.
A spot of physics – insulation vs conduction
Materials have properties that either make it very easy for heat to pass through or very difficult to pass through, or somewhere in between. Good insulation can be understood as a substance that is difficult for heat to pass through. Good conductors, on the other hand, are substances that are easy for heat to pass through. These traits are mutually exclusive, meaning that an excellent conductor of heat is a poor insulant, and an excellent insulant is a poor conductor. Both have their merits, and materials are selected depending on the application.
Common applications for conductors and insulation
The kitchen is a perfect example of physics in action. The handles of kettles and utensils are made of bad conductors of heat such as wood, plastic, ebonite, etc. They help in holding them comfortably. The actual saucepan needs to be made out of a good conductor, so that the heat from the stove top can pass through the pan quickly to cook the food. Oven mitts, conversely, have high insulating properties so the heat from saucepans and oven trays isn’t able to pass through and burn the chef’s hands. Heat pot stands are often used to protect bench tops from being damaged by hot saucepans and frying pans. That’s on the small scale.
So, in terms of housing Australia, what does insulation mean?
If we know how to keep our cup of coffee hot for hours, and we know how to keep our drinks chilled on a hot day, what’s to stop us from using that knowledge on a large scale? That’s where domestic and commercial insulation comes into play in a big way. Our next article will explore how an effective building insulation solution can create a comfortable home without excessive use of heating and cooling systems.