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Are there any rebates?

Many states are offering financial incentives to increase the insulation in your home. Check your locale to see what you might qualify for.

How do I know if I have a problem?

Evaluate all areas of your home that are insulated and verify that they meet the minimum standards for each area. Some people like to add additional insulation in areas where there is plenty of room, especially up in the attic.

What you might want to do is evaluate areas of your home that might not be insulated, but certainly could be. Look for:

-> Ceilings with unheated spaces
-> Basement walls
-> All areas above vented crawl spaces
-> Cathedral ceilings
-> Kneewalls (the short walls in a finished attic)
-> Between interior walls such as bathrooms
-> Floors over unheated garages or porches
-> Anywhere you want additional sound control

How much do I need?

The U.S. Department of Energy (DOE) and the International Energy Conservation Code have established minimum recommended levels of insulation based on each climate zone. This will vary based on where you live.

To add insulation, do I have to remove what's already there?

Absolutely not! In fact, many home owners roll out additional layers of insulation on top of the insulation that is already down, especially up in the attic. Even better, if you originally had insulation at an R-value of 19 and you added another layer of the same value, your resulting insulation R-value would be 38. When adding additional layers, be sure to use unfaced batts and lay them cross-wise across the existing layer.

What are my choices?

Homeowners have many choices when it comes to insulation. There is cellulose, cotton, foam, mineral wool, and fiberglass. Most people are familiar with either cellulose or with fiberglass.

When choosing insulation for your home you want to make sure that you meet at least the minimum requirements for your climate zone. You also want to invest in an insulation that will provide long-lasting thermal protection. You really don't want to have to go in and replace the insulation of your home every few years. This means that you want an insulation that will not deteriorate or settle over time.

Fiberglass and rock and slag-wool do not settle much more than about 3% over their lifetime. Cellulose insulation will settle at least by 20% and sometimes as much as 50% if it were to ever get wet. This is why the Insulation Contractors Association of America recommend using 25% more cellulose insulation to counteract these losses in your R-value.

What are the environmental ramifications of each?

More and more builders are responding to the request that they become more environmentally conscious and are using more and more materials that have a lower environmental impact. Fiberglass insulation is made up recycled products, and recycle more material by weight than any other type of insulation used in the building industry. You are encouraged to look at the full lifecycle of fiberglass insulation versus cellulose insulation. While cellulose insulation is mostly made from recycled newspaper, it actually removes the newspaper from that recycling loop, causing more trees to be used to create new cardboard and newspaper for to replace the materials that have been used as insulation. It takes nearly three times as much cellulose to provide the same R-value as fiberglass. Both types of insulation use about the same amount of virgin material, but because fiberglass is made from sand it is classified as “rapidly renewable resource” as opposed to cellulose.

What does R-value mean?

R-value represents the insulation's resistance to heat flow. The higher the value, the greater its insulating capability.

What is air infiltration?

Air infiltration is due to air leaks in your house. Up to 40% of a home's energy loss can occur due to air infiltration, with about 14% being due to the side wall cavities. This can be minimized by sealing all electrical outlets with specially made gaskets.

Air infiltration is a problem in areas of the home that isn't insulated. The areas around fireplaces, windows and doors, ductwork, and perimeter joints. This should be controlled by proper sealing techniques with either caulk or other sealant. Typically, insulation has very little to do with air infiltration. If a wall is built and sealed properly, there will be very little air infiltration regardless of the type of insulation that is used.

What is the purpose of insulating?

Insulation works to prevent the flow of “conditioned” air from leaving the area you want comfortable. In the winter, insulation keeps your home warm. In the summer, it keeps the cool air inside. Insulation resists the flow of heat. Heat, as a form of energy, likes to move from where it is hot to where it is cooler. By preventing the flow of heat from moving out of your house in the winter, and into your house in the summer, you'll save a lot of money on your energy bills.

One additional reason for using insulation is for sound control. Many home owners are now adding a lot more insulation in bathroom walls for greater sound control. You may wish to consider additional insulation in the walls, ceiling, and floor of a home theater to keep the sound inside that room.

Which one is more efficient?

When installed properly and not exposed to moisture, both cellulose and fiberglass will provide an adequate R-value of insulation.

Which one is safer?

Cellulose is made from wood fiber in the form of ground up or shredded newspaper. and is extremely combustible. Most cellulose insulation has to be heavily treated with fire retardant chemicals. Even with the fire retardants, it is not fireproof. Studies have also indicated that fire retardant chemicals lose their effectiveness over time. The California Bureau of Home Furnishings and Thermal Insulation showed that cellulose can fail the standard test only six months after installation.

Fiberglass is naturally noncombustible because it is made of sand and recycled glass.

Which one isn't affected by water?

When fiberglass gets wet, it does not compact, and once it dries out, it retains its original R-value rating. When cellulose gets wet, it compacts dramatically, and once it dries out, it has lost over 50% of its R-value rating and must be supplemented with additional insulation. It will never again regain its original R-value rating.

There is a wet-spray method of applying cellulose that is designed to counteract this problem, but it can delay building schedules dramatically. If walls are covered up before the wet-spray cellulose is completely dry, the homeowner will be dealing with other problems due to moisture such as deterioration of building materials and future problems with mold and mildew.