Energy Savings from Insulation
Your home is insulated from the outdoor environment. However, the amount of insulation can vary extremely. Older homes may lack much insulation while newer homes can be well insulated. Insulation is a key factor in how much you spend for electricity and natural gas.
What You Can Do to Save Energy
Check for the amount and condition of insulation where possible, like above the ceiling. |
Insure protection against moisture. |
Add insulation where possible. |
Impact of Your Energy Saving Actions
46% of your heating and 24% of your cooling energy is through materials that are insulated. With almost half of your annual utility bill going to heating and cooling, then improved insulation will have an impact. If your insulation is poor, then your percentages will be much higher than the averages. Insulation improvements are moderate costs with good payback.
How Energy is Lost
Heat can flow through solid materials. This is called conduction. Heat conducts through your windows, doors, walls, ceiling, floor etc. As long as their is a temperature difference, then conductive heat transfer will occur. It is impossible to stop, but it can be tremendously slowed. Heat conducts poorly through gasses; the molecules are much farther apart than a solid. If a gas, like air, can be placed in the path then heat flow can be reduced. Problem is that air can too easily move increasing another form of heat transfer called convection. So the objective is to have a material full of air that cannot move around. That is what insulation is, an air trap. The better the insulation is at preventing air from moving, the better it insulates. Some insulations like polystyrene have small closed cells which hold air in place. This type of insulation is a very good thermal insulator. A blow-in cellulose often found above the ceiling, cannot completely trap air. Air can move some through the insulation. It takes much more to equal the insulation capability of polystyrene.
Insulation Characteristics
Insulation is listed by it R-value or sometimes called R factor. The R-value or resistance value is an indication of how difficult it is for heat to conduct through the material. The higher the R value, then the better insulation. Sometimes the R value may be given for each inch of thickness.
Energy Solutions Explained
You should have the appropriate amount of insulation; and that insulation must be installed properly. Insulation should have complete coverage of the area. Insulation should be at its intended thickness, not compressed into a space. Proper support for the insulation when necessary like under the floor in crawl spaces. If you have loose fill above your ceiling, then make sure it is spread evenly across the attic.
Insulation works because of air within its fibers. If the insulation gets wet, then water replaces the air and the insulation capability dramatically reduces (not to mention the potential for mold).
Consider adding more insulation above the ceiling or below the floor over crawl spaces. Department of Energy recommends R-49 above the ceiling. For loose fill insulation it would need to be about 20 inches deep.
