5 Types of Insulation

Insulation in the walls of a home.
  • 4-8 hours
  • Beginner
  • 1-2,500

Insulation is a necessity in every home and it comes with many benefits like keeping you warm in the winter and cool in the summer. Plus, it can deaden noise and offer fire resistance. It can also cause problems like promoting mold grown or enticing pests. Trying to decide what kind of insulation materials to use is a balance of environmental factors, personal preference, budget, and efficiency (R-value). Here are some pros and cons of 5 types of insulation to help you in the decision-making process.

1. Fiberglass

Fiberglass has been used for decades as an effective insulation tool. It is made from fine particles of glass. It can be found in blanket form, called batts, or rolls. It is also available in loose form. The rolls are convenient for standard applications while the loose-fill is handy for awkward spaces. Always install this product with the paper backing facing into the room.

Pros: Fiberglass is easy to install since it often comes in rolls that are pre-measured to fit between joists, studs, and rafters. It also comes in standard thicknesses, each with their own R-value rating. Just make sure to cut around pipes, wires, and outlets with a snug fit. Even small gaps can lead to big air leaks. Fiberglass is a product that was green before it was en vogue since it contains up to 60 percent recycled materials, although that can also be as low as 20 percent. It is the least expensive type of insulation.

Cons: Fiberglass is long-known to be a skin and lung irritant. It easily compresses, which can change the effectiveness of the insulation.

2. Mineral Wool

Mineral wool is made from hotly melted glass, stone, basalt, or industrial waste known as slag and turned into rolls similar to fiberglass.

Pros: It doesn’t irritate the skin and lungs. It also offers a high level of fire resistance. Mineral wool springs back from compression during installation. It is up to 90 percent recycled post-consumer materials. It is also good for noise suppression.

Cons: Mineral wool is more expensive than fiberglass.

3. Cellulose

Cellulose insulation is one of the oldest forms of insulation. This category includes all organic materials such as paper, hay, cardboard, cotton, straw, sawdust, hemp, denim, and corncob. It comes in loose-fill and blow-in varieties. It is chemically-treated at a rate of around 15 percent. The chemicals used are not known to harm humans, but repel pests.

Pros: Organic materials made from paper and other products are used in cellulose insulation. It uses around 85 percent of post-consumer materials. Cellulose insulation is also good for soundproofing. It is very effective at filling even the smallest spaces when blown in. It is also inexpensive.

Cons: Cellulose insulation can settle up to 20 percent. Due to its weight, it does not work well in attic spaces. Moisture can make it heavier and reduce its effectiveness.

4. Polyurethane Foam

Spray insulation.

This spray foam, made from a polyurethane substance, is applied using a spray gun. It then grows or expands to fill the space. It can be found in small canisters (spray can), professional packs that are used with a sprayer, or you can hire someone to do the job.

When considering polyurethane foam, keep in mind that there are two different kinds — open cell and closed cell. Open cell is less dense because it is lighter and offers a lower R-value. It is also less expensive. In addition to being more expensive and denser, the closed-cell option can also act as a water vapor barrier.

Pros: It applies and dries quickly and is water-resistant. When applied correctly, the foam offers superior air leakage protection. It is a great option for tight spaces.

Cons: If not installed properly, it can leave large gaps that lead to inefficiencies. It contains a lot of chemicals and has a high environmental impact. There is a lot of room for error and is better installed by a professional.

5. Polystyrene

This foam insulation makes an effective noise barrier, lasts a long time without breaking down, and is waterproof.

Pros: It is bug-resistant when small amounts of concrete are added. It has a uniform and consistent application.

Cons: It has higher upfront costs than other options, balanced out with long-term savings. It is flammable and often treated with chemicals.

Helpful Hints

A man installs insulation.

When your project is complete, shower in cold water. Warm water encourages pores to open, which can exacerbate the itch from any glass fragments. Wash all clothing that came into contact with the insulation in one load. Do not mix other clothing into the load as they can pick up the glass fibers. Always wear long sleeves, pants, gloves, eye protection, and a mask when handling insulation.