Understanding Batt Insulation

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What is Batt Insulation?

April 17, 2012

The most common form of home insulation is “Batt and Roll” or “Blanket” insulation. It is typically stored in rolls, is generally made of fiberglass and is the least expensive way to insulate a home.

Easy to Install

Batt and roll insulation is manufactured in various sizes for easy transport, and to make the installation easy for everybody from contractors to do-it-yourselfers.

Air Seal Before Insulating

Insulation helps save energy by preventing heat transfer either into or out of your home (depending on the climate). But insulation is not effective at stopping air from infiltrating through gaps and cracks in the home’s exterior shell, or envelope. Therefore, for the insulation to be effective, you must seal air leaks before adding insulation.

Higher R-Values Insulate Better

Like all insulation, batt and roll is rated on an R-Value scale, which measures the thermal resistance – the effectiveness to prevent heat transfer – of the material. The R-Value increases with the density and thickness of the insulation. A higher R-Value means better insulating properties – and a higher the cost.

The following chart shows how the thickness, R-Value and cost of the insulation rise together (note: cost is approximate and may vary by location):

Thickness (inches) R-Value Cost (cents/sq. ft.)
3 ½ Inches 11 12 – 16
3 5/8 Inches 13 15 – 20
3 ½ Inches (High Density) 15 34 – 40
6 to 6 ¼ Inches 19 27 – 34
5 ¼ Inches (High Density) 21 33 – 39
8 to 8 ½ Inches 25 37 – 45
8 (High Density) 30 45 – 49
9 ½ Standard 30 39 – 43
12 38 55 – 60

Better Insulation Reduces Heating and Cooling Costs

While different R-Values are recommended for different climate regions, you can always benefit from installing a higher rated insulation. Although the initial cost will be greater, your home will be better insulated and require less energy for heating and cooling. A more energy efficient home may command a higher resale value and help you sell faster. Find the recommended insulation for your climate using the Department of Energy’s Zip Code Insulation Calculator.

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