More than 90% of homes in the U.S. are underinsulated, meaning they do not have the recommended amount of insulation for their climate. Due to this and continued rising energy costs, more homeowners are looking at installing insulation in their homes than ever before.
There are many choices on the market for insulation today, which can make it confusing for homeowners to know which is the right choice. Added to that, there are many different price points and even some health concerns to consider about the various insulation types.
This graphic helps you see at a glance the different, commonly used insulating materials for homes, how expensive they are (for a 1,500-sq.ft. space), and how healthy they are to use in your home.
Percentage of Use: 11%
Average Cost: $3,190
Health Rank: Medium-High Risk
Foam board is most commonly made of either extruded polystyrene or expanded polystyrene. Both materials are rigid foam insulators that typically come in boards. The differences between them are primarily in density and how they’re made. Extruded polystyrene (XPS) pulls or extrudes the material to create a denser foam. Expanded polystyrene (EPS) starts as a liquid that expands into its final shape. It’s lighter and less dense.
Both are used to insulate the exterior of your home and helps create a tight building envelope. Foam board scores low in percentage of use, while costing the most. Polystyrene off gasses, meaning it releases volatile organic compounds (VOCs) into the environment over the course of 5 years, with 50% off gassing in the first year. This can pose a potential health risk for consumers, but because it is used primarily in the exterior region of the home, this risk may be somewhat mitigated.
Percentage of Use: 11%
Average Cost: $2,065
Health Rank: High Risk
Spray foam insulation is also made of expanded polystyrene, but it begins as a liquid that is sprayed into cavities in your home. It also gets about 11% of total usage but costs less than foam board. It is used in home interiors in places that need a tighter seal or may be hard to insulate with other materials, such as the underside of a roof deck. It also produces high levels of VOCs, but because it is indoors, its risk to homeowners is much higher than foam board or other insulations.
Percentage of Use: 19%
Average Cost: $1,315
Health Rank: Low Risk
Blow-in fiberglass is the second most popular insulation at 19% of total usage. It is made of the same material as fiberglass batts but is loose and able to be blown into cavities to fill them better. It can reach difficult-to-insulate areas in the attic and walls. It is the third most expensive material, however, costing more than other blow-in materials or fiberglass batts. All fiberglass is considered to have little-to-no health risk, making it the safest choice for homes.
Percentage of Use: 5%
Average Cost: $1,250
Health Rank: Medium-Low Risk
Cellulose is also a blow-in insulation, which gets 5% of total usage. It is made primarily from recycled newspaper and similar material that has been treated to make it less flammable. It is also good for using in cavities in attics and walls and costs slightly less than blown-in fiberglass. It also carries a slightly elevated health risk, mostly due to eye and mucous membrane irritation for the people installing it.
Percentage of Use: 1%
Average Cost: $865
Health Rank: Moderate Risk
Mineral wool is a lesser used insulation, making up 1% of total insulation usage. It is made of slag material, or waste material left over from the production of things like glass and steel, that has been spun into fibers and is usually installed as panels or boards in home interiors. It is less costly than most other insulation forms but has a higher health risk. This is because those fibers can break off and become airborne, where they are at risk of being inhaled. This can cause irritation and respiratory distress.
Percentage of Use: 52%
Health Rank: Low Risk
Fiberglass batts are the most commonly used type of insulation at 52%. It is also the lowest in cost and like all fiberglass carries little-to-no health risks. Batts are typically used between studs in places like the attic and the walls of your home.
At a glance, it is easy to see that fiberglass batts and blown-in fiberglass outrank any other material overall. On its own, fiberglass batts make up more than half of the insulation used in the home, and combined with blown-in, the two make up more than 70% of all insulation. Both also receive the best ranking for health. This makes sense considering the fact that of all the insulation types, fiberglass has undergone the most inspections and has been determined to contain no known carcinogens and is notcombustible, making it one of the safest materials to use as insulation.
Fiberglass batts are also the least expensive material shown, coming in at just $560. Consider that insulating an entire home costs an average of $3,500 to $4,500 when using a combination of sprayed foam and blown-in insulation. So, switching to batts for at least some of this job could save you a significant amount of money.
What is also interesting to note in this graphic is the two foam insulations and how poorly they rank when compared to others, each capturing only 11% of the market. But with the greater emphasis being placed on the tight building envelope, this low percentage is surprising because foam is one of the few insulations that can be used in this capacity. While fiberglass and cellulose make great choices for interiors, foam board is necessary for the exterior, and spray foam is frequently used to coat things like the underside of the roof deck.
Of the two, spray foam is much less healthy. This is mostly due to the nature of the product and the VOCs it off gasses both during application and after. Foam board insulation is the most expensive, while also scoring lowest in the health category.
Also surprising is how low cellulose scored. Many people choose it over fiberglass for blown-in insulation, yet it scores lower in percentage used and in health. It is slightly less expensive than blown-in insulation, however, which may make it a better choice from a cost standpoint where blown-in insulation is required.
There are obviously more considerations to make when choosing insulation, such as the area being insulated, whether it is new construction or an existing home, and how easy the area is to reach. But if you have choices for which material to use, weighing your options by comparing both cost and health can help you make a better choice for your home.