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How to Insulate a Home

You can be comfortable, save money and reduce energy use with insulation.

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Step 1: Watch an Overview Video

Step 2: Choose a Type of Insulation

When choosing insulation, consider R-values, which measure how well insulation holds back heat. R-values depend on material type, thickness and density. The higher the R-value, the better the insulating power. The R-value of various insulating materials is based on test methods set by the American Society of Testing and Materials (ASTM).

Next, decide on the type of insulation. Fiberglass insulation comes in rolls and batts and in various lengths. There are four basic types of insulation. Rolls or blankets are flexible products made from fiberglass and rock wool. Loose-fill insulation, made of fiberglass, rock wool or cellulose comes in shreds, granules or nodules. Rigid foam insulation is more expensive than fiber insulation. However, it works well where there are space constrictions or with higher R-values needed. And foam-in-place insulation is blown into walls and limits leaks from air.

Step 3: Consider Environmentally-Friendly Insulation

You can go green with recycled cotton or cellulose insulation that’s blown into attics or walls. It’s mostly recycled newspaper and is fire and insect resistant. In either case, always wear protective gear. Ventilation helps moisture control and reduces cooling bills. You can put attic vents along the entire ceiling cavity for better airflow.

Step 4: Keep Insulation Away from Heat Sources

Keep a 3" safe zone between insulation and heat sources like heating and cooling lines, recessed lights or chimneys. If building new, help reduce utility bills by insulating exterior walls to the best energy efficient level. Homes even 10 years old may be below today’s recommendations, so add insulation where it’s needed in crawl spaces or on basement walls. When adding to an existing insulation, make sure you use un-faced fiber glass or mineral wool insulation.