Understanding how insulation works

Insulation is seldom a focus of our attention, yet it effects our daily lives. Heating and air-conditioning cost are continually going up, and without proper insulation, we are literally throwing money away.

Unscrupulous contractors often take advantage of home owners wanting to improve their insulation. To avoid being "taken", you need to be educated on what works and what does not help.

To start with, let's look at the type of insulations available. The classic pink rolls, as shown in the photo above, are still one of the main ways homes are built. Many people presume that packing in more insulation will make the wall more efficient. This is not true.

Insulation works by creating resistance to heat flow. There are three avenues for heat to move. Conduction is heat traveling within a material. Convection is heat moving as a gas circulating upwards as cold moves downwards. Radiant heat moves in a straight line transferring to other solid objects.

With this in mind, we are doing what we can to inhibit those three directions of flow. And with that thinking process, we can clearly see that one form of insulation is not the answer.

               Location becomes as important a factor as how much and type of insulation.

Doors, windows, foundations, all need to be taken into consideration. But as you can see, walls and ceilings are the highest percentage. Walls are the most difficult to insulate due to the simple fact there is not as much room to insulate as in the attic.

One way to get your mind to understand this concept is to consider building a structure with walls but no roof, or with a roof and no walls. Factors that would suddenly come into play is heat loss upwards, or wind moving the heat away from you on all sides.

Contractors will tell you that your home needs more insulation, and charge to blow an additional foot into your ceiling, but with this knowledge, you know that although that will help some; it will not solve the insulation needs in your home.