Understanding the Importance of Insulation

If you're like the vast majority of homeowners you're concerned about the costs of heating (and cooling) your home. There's a good reason for your concern, the US Department of Energy estimates that just under half (44%) of the energy used in the average American home goes toward either heating or cooling the home. However, there is some good news, the DOE estimates a homeowner may be able to reduce their heating bill by 10% to 50% simply by increasing the amount of insulation installed in their homes.

Air naturally tends to move from warm areas towards colder areas and insulation restricts this natural movement. So, during the cold season, insulation prevents cold from coming into the house through the ceilings or walls, (it works the same way during the hot summer, keeping the cool air inside the house and blocking it from moving towards the warmer area outside.

Insulation should be installed in any barrier (wall or ceiling) the stands between cold air and warmer air or unheated spaces and hated spaces. So, in a typical home the most important areas to have well insulated are the ceiling, the walls and the basement. Crawl spaces and garages are also areas where insulation can be added to reduce heat loss.

Insulation is measured by its R-value, - it's resistance to heat flow. The higher the number, the more blocking capacity or insulating it provides. Different materials have different heat blocking capabilities, therefore different R-values. As well, the thickness of the insulation, where it's installed and how well it's installed will determine the total R-value of the insulation in your home. Since R- values are cumulative (they add together) the total R-value is the sum of the R-values of the insulation in any particular area of your home.

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