There are many types of insulation products and 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 ready to weigh in on what they believe is the best insulation system.
CIMA’s goal here on the website is to provide consumers with the facts so they 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 cellulose insulation and various types of insulations.
While there are a large number of materials that could be used to insulate a home, the most used forms of insulation on the market today are:
Cellulose insulation has been a tried and true method of insulating homes for decades. It is made from recycled newsprint and other recycled paper with one of the highest percentages of post-consumer waste content of any insulation. It is treated with recognized safe fire retardants. Numerous tests have shown that cellulose insulation is better at preventing the spread of fire in a building than other insulation products.
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 insulation a perfect choice for insulating attics and sidewalls.
Cellulose insulation is blown onto attic floors or into wall and ceiling cavities, or is sprayed into open wall cavities. It is an excellent choice for adding insulation in walls of older existing homes due to the ease of installation.
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. Its most common forms are rolls and batts, which are used in wall cavities and attics and also in a loose-fill form that is blown-in.
Fiberglass is non-combustible, but it will melt in a fire, potentially allowing that fire to spread. 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 insulations are petroleum-based products and typically have little or no recycled content. 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.
Ingredients derived from soy or castor beans are being added to some foam products in an attempt to produce a less environmentally harmful product. They also require professional installation and provide similar air leak reduction as standard spray foam insulations. According to Environmental Building News, these products contain approximately 40% bio-based ingredients and 60% petroleum derived products. It should also be noted that petroleum is used to drive the farm equipment and to produce the agri-chemicals used to grow beans.
Another high recycled and more unusual product is recycled denim insulation. The insulation is primarily made with pre-consumer recycled cotton or denim waste collected from factories manufacturing jeans and other denim products. There are now some with programs targeting post consumer recycling of jeans and other denim products from consumers.
This product is environmentally friendly as it is made from a rapidly renewable resource. Performance is similar to other insulation batt products. It is easier to install than fiberglass since it does not contain the glass fibers. The cost to insulate cotton/denim is typically significantly higher than other materials and the product is not as readily available to consumers in many areas.
Learn more about the key performance features for these most common types of insulation products here on the CIMA website.