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What Is Insulation? Why Is It Needed?

man installing fiber glass insulation

Insulation is a vital material in any home that works to keep you warm in the winter and cool in the summer. It consists of many materials and has many uses. Keep reading as we look into the different types and discuss their advantages and disadvantages to help you be better informed.

divider 4 How Does Insulation Work?

Insulation creates a barrier between you and the outside environment because it resists heat flow. Heat tries to leave your home in the winter. If it escapes, you must turn on the heater more often, which will raise your power bill. In the summer, the opposite happens, and heat creeps into your home from the outside. Incoming heat will raise the internal temperature, causing you to turn on the air conditioner. You can tell how well your insulation blocks heat flow by looking at the R-value printed on the packaging. The higher the R-value, the better the insulating power. You can increase the value by adding more insulation.

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What Are the 5 Different Types of Insulation?

There are several types of insulation, each with an R-value, so you will need to check your packaging to see what you have, but here are a few of the most popular types.

1. Blown Fiberglass

Blown insulation in attic
Image By: Lara Makela, Shutterstock
  • R-value of 2.2–2.9 per inch

Blown fiberglass is a type of blown-in insulation or loose-fill insulation. It’s a great choice for attics and ceilings and works well to fill walls and other small, hard-to-reach areas.

2. Fiberglass Batt

a person installing stone wool insulation for soundproofing
Image Credit: Erik Mclean, Pexels
  • R-value of 2.9–3.8 per inch

Fiberglass batt insulation is the kind that most people recognize. It often looks like a thick piece of pink foam with paper on one side. It works great in the attic and other areas of the home. Since it is easy to get and put into position, you may be able to install it yourself if you wear protective equipment and are only installing a few pieces.

3. Blown Cellulose

blown cellulose insulation filling in hand
Image Credit: gokcentunc, Shutterstock
  • R-value of 3.1–3.8 per inch

Blown cellulose is similar to blown fiberglass except for the ingredients in its construction. It often uses wood or paper fibers instead of fiberglass, and you can often purchase brands that use recycled material, which enables the insulation to be more environmentally friendly.

4. Loose Rock Wool

Mineral Wool
Image By: RachelW1, Pixabay
  • R-value of 2.2–3.3 per inch

Loose rock wool is a loose-fill insulation that manufacturers create by spinning molten rock into a fibrous material that works well for insulation. It’s resistant to moisture and mold and works well in cold weather. It doesn’t break down as easily as fiberglass, so it’s a good outdoor insulator.

5. Sprayed Foam

man applying spray foam insulation on the walls
Image Credit: Igor Meshkov, Shutterstock
  • R-value of 3.6–8.2 per inch

Spray foam is one of the strongest but messiest types of insulation. It helps fill air gaps, reduces drafts, and is easy to spray into hard-to-reach places. It doesn’t lose its shape and won’t settle over time, so it will last for many years, but the foam often gets everywhere and looks unsightly, so many people avoid it in areas with a large amount of traffic.

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How Much Insulation Do I Need?

Typically, people in a warm environment will want the insulation in their attic to have an R-value of 30, while homes in a cold climate usually want a value closer to R-60. So, with blown fiberglass with an R-value of 2.5 in a cold environment, the insulation would need to be about 24 inches thick. If you’re using a spray foam with an R-value of 8, you would only need about 7.5 inches of insulation.

roll insulation
Image Credit: AKuptsova, Pixabay

Where Is It Used?

People use insulation in many areas of the house, including the attic, around pipes and ducts, walls, and floors. You can also find insulating materials in your vehicles, coolers, thermoses, and many other objects.

Advantages of Insulation

The main advantage of insulation is that it prevents heat from escaping your home in the winter, reducing energy costs and making it easier to prevent pipes from freezing and other problems that can occur in cold weather. It also helps during the summer because it prevents hot air from getting into your home, which will cause you to use your air conditioner more often. In addition, some insulation can help reduce drafts and improve indoor air quality by reducing dust levels. Most insulation is fire-resistant and can also help prevent insects, mold, and moisture.

Installing basement insulation_Juice Verve_Shutterstock
Image Credit: Juice Verve, Shutterstock

Disadvantages of Insulation

Unfortunately, many types of insulation can be quite expensive, especially if your home initially has little or no insulation. In many cases, you will want to hire a professional to install it, which will also increase costs, and some types, like spray foam, will require you to leave the house for 12 hours or more.

divider 1 Frequently Asked Questions (FAQs)

Do I need to insulate the exterior walls of a foundation on a new home?

Homes in a warm environment usually won’t require insulation around the exterior walls. However, houses in a cold climate can increase the R-value of the foundation with 2-inch foam boards added to the exterior walls before the builders fill the area with dirt.

What type of insulation should I use on exterior walls?

One of the most popular insulations for exterior walls is fiberglass batt. It’s easy to cut and fit into small areas and usually has a high R-rating. Another popular choice is cellulose, which you can blow or pour in.

removing attic insulation rock wool
Image Credit: LianeM, Shutterstock

How important is attic insulation?

Heat rises, making the attic one of the most important places in your home to install insulation. Insulating the attic floor will create a barrier, preventing your expensive heat from escaping. Attic insulation can also prevent condensation and mold growth.

Can I install the insulation myself?

You can install fiberglass batt in your home, but many people hire a professional to do it instead because the fiberglass is itchy if you don’t have experience working with it. Blow-in and loose-fill insulation require special tools, so you cannot install them yourself.

How much does installing insulation cost?

Several factors affect how much your home insulation will cost, including building size, type of material, climate, and contractor costs. However, the average price is $1,400–$2,300.

divider 4 Conclusion

Insulation can be any of several materials that work to prevent the escape of heat from the home in winter, which can help keep us more comfortable. It also helps prevent heat from entering the home during the hot summer months, so the air conditioner doesn’t need to work as hard. Since you won’t need your heater or air conditioner as often, you can experience considerable cost savings and do less damage to the environment. While it can be costly and usually requires hiring a professional, installing insulation is often worth it in the long term.

Featured Image Credit: Christina Richards, Shutterstock


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