What types of insulation are available?
There are many insulation options available, all with competing claims, making it a challenge to sort the facts from the advertising. There’s also no shortage of self-proclaimed experts all ready to weigh in on what they believe is the best insulation system.
Our goal is to provide you with the facts, so you can develop an informed opinion without relying on advertising or unsupported comments.
This summary, and the other comparison charts appearing in this site, will focus on the performance and environmental characteristics of various insulations.
While there are a large number of materials that could be used to insulated a home, the most used forms of insulation on the market today are:
- Cellulose
- Fiberglass
- Spray Foam
- Cotton / Denim
Cellulose
Made from recycled newsprint and other recycled paper, and treated with nontoxic fire retardants, cellulose insulation has been a tried and true method of insulating homes for decades. Its excellent sound insulating properties, its ability to provide an effective 1-hour fire rating, high R-value per inch, and industry leading environmental properties, makes cellulose a perfect choice for insulating attics and sidewalls.
Fiberglass
Fiberglass insulation is made from molten glass that is spun or blown into fibers. The recycled content of fiberglass insulation ranges from 0-40%, but that includes waste generated during manufacturing. Fiberglass also doesn’t decompose once it’s put into a landfill. Its most common forms are rolls and batts, which are used in wall cavities and attics.
Fiberglass is non-combustible, but it will melt in a fire, potentially allowing that fire to spread. Numerous tests have shown that cellulose insulation is better at preventing the spread of fire in a building.
Care should be taken when installing fiberglass to wear protective clothing and a respirator, per the manufacturer’s guidelines, to avoid direct contact with, or inhaling of, the glass fibers.
Spray Foam
Spray foam insulations are petroleum based products. They require professional installation, using special equipment to measure, mix, and spray the foam. Due to their ability to help reduce air leaks, they are often used in selected areas where the reduction of air leaks is critical, although it can be used throughout a structure. The cost to insulate using spray foam is typically significantly higher than other materials. Excess sprayed foam insulation from the job site can’t be reused, nor can it be recycled.
Soy-Based Foams
Soy-based ingredients are being added to foam products in an attempt to produce a less environmentally harmful product. According to Environmental Building News, these products contain approximately 40% soy-based ingredients and 60% petroleum derived products. However, it’s a misnomer to say these products are soy-based, as soy products aren’t the primary ingredients.
Cotton / Denim
One of the most talked about insulation material is recycled denim insulation. The insulation is made with pre-consumer recycled cotton or denim waste collected from factories manufacturing jeans and other denim products. This product is environmentally friendly as it is made from a rapidly renewable resource.








