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57 Ways To Protect Your Home Environment (and Yourself)
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53. Insulate And Seal Your Home

batt insulation

The insulation that you apply to walls, ceilings, and foundations saves fuel, saves money, and makes your home more comfortable. All insulating material is rated according to “R-values,” which indicate a material’s ability to prevent heat from flowing into or out of the house. The higher the R-value, the more effective the insulation.

Batt insulation is sold in rolls or blankets of various thicknesses, and most of it is made of fiberglass. Batt insulation is moisture-resistant, but not very resistant to vapor, so apply a polyethylene vapor barrier on the warm side of batt insulation. It has R-values that range from 3.1 to 4.3 for every inch of thickness.

loose-fill insulation

Loose-fill insulation can be made of fiberglass, rock wool, or cellulose treated with a fire-retardent. It has an R-value that ranges from 2.2 to 3.7 per inch, and is often blown into attics and walls. Loose-fill insulation is resistant to fire, but moisture can reduce its effectiveness.
ridgid foam boards

Rigid foam boards are made of different types of plastics and have R-values that range from 3.8 to 8 per inch. It is a good choice for insulating finished basement walls and the outside of a foundation. Some plastics are highly flammable and produce toxic smoke when burned, so building codes require a barrier, such as drywall, to protect the boards from heat and flame.
plugging holes and cracks with weatherstripping

In addition to insulation, plugging holes and cracks with weatherstripping and caulking are good ways to keep drafts out and lock heated or cooled air inside your house. Even a small crack can let in a large amount of air. For instance, a 36-inch by 80-inch door with a 1/32-inch crack (thinner than a dime) around the edges lets out as much heat as a 7-1/4-square-inch opening.
u value

With insulation, you want to look for high R-values; but with windows, you’re looking for low U-values. U-values rate the energy efficiency of windows. The lower the U-value, the less a window will conduct inside heat to the outside.
single glazing

The poorest insulator in your house is single-pane glass. U-values may vary due to glass thickness, frame type, and coating, but single-pane glass typically has a U-value of about .94. Adding layers of glass can help reduce heat loss, because as more panes are added, the U-value decreases.
double glazing

Double-glazing, or two layers of glass, cuts heat loss almost in half. The U-value ranges from .39 to .48.
triple glazing

Triple glazing cuts heat loss by two-thirds when compared to single panes (although it may also decrease light entering the house by 10 percent). U-values drop down to a range of .27 to .38.
installing insulation

Keep in mind that by tightening up a house with insulation, weatherstripping, and caulking, you may reduce the number of “air changes per hour” in a home, thereby increasing the level of indoor pollutants. Test for carbon monoxide and other pollutants (such as radon) before and after the weatherization work.
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