What's the Best Insulation for a Home?
Upgrading your home’s insulation is one of the best things you can do to improve its comfort and energy efficiency. But an insulation upgrade is not a one-size-fits-all project. There are many types of insulation and they don’t all offer the same level of quality and performance.
Sustainergy Cooperative offers free energy assessments to evaluate your home and recommend the best insulation for your specific situation. Our free assessments are no-pressure and designed to help you find a high-impact, low-cost solution for your insulation needs.
In the meantime, we’ve put together a guide to home insulation to help you learn more about the options available to you.
Types of Insulation
The most common types of insulation for existing houses are loose-fill, blanket, and spray foam.
Blown-In Insulation
Blown-in insulation (also known as loose-fill insulation) is typically made from fiberglass or cellulose. It’s installed with a hose that blows the material into the space. It can be installed in open spaces like an unfinished attic floor or dense-packed into closed cavities. Loose-fill insulation will conform to the space it's installed in without disrupting wires, pipes, and existing structures.
Blanket Insulation
Blanket insulation comes in batts and rolls. It’s made from flexible fibers—typically fiberglass—though it’s available in a variety of materials. It usually has a paper backing that serves as an air barrier and makes handling and installation easier. Blanket insulation comes in standard widths and is the best option for DIY insulation installations.
Spray & Injection Foam
Foam insulation can be sprayed or injected into a space, depending on the need and application. Injection foam can be installed into empty wall cavities, and spray foam is applied directly onto open surfaces such as walls and ceilings. Spray foam insulation is dangerous when not installed correctly and requires professional installation.
Insulation Materials
Insulation comes in many different materials, but these are the most common.
Cellulose Insulation
Cellulose is an insulation material made primarily from recycled paper that’s been treated with borate, a non-toxic, Class A fire, pest, and mold repellent. It’s an excellent insulator and it can also reduce air infiltration—something many insulation materials can’t do. Cellulose insulation is typically either blown-in or dense-packed and is the best type of insulation for attics, enclosed walls, and other hard-to-reach areas.
Affordable
Fire-safe
Pest-resistant
Eco-friendly
Sound-attenuating
Fiberglass Insulation
Fiberglass insulation is one of the most common insulation materials, but that doesn’t mean it’s the best choice. It’s made by spinning molten glass into extremely thin fibers that are then blown in or attached to paper backings to make batts. While it’s affordable, fiberglass batts are prone to gaps and compression that greatly reduce their effectiveness.
Affordable
Readily available at big box stores
Hazardous when mishandled
Can attract pests
Spray Foam Insulation
Spray foam insulation is installed as a liquid that expands to fill the area it’s applied to and hardens. There are two primary types of spray foam: open cell and closed cell. Open cell has a typical R-value of 3.8 per inch, and closed cell has an E-value of 7 per inch. The primary differences between the two is density, cured hardness, and that closed cell is a vapor barrier and open cell is not, so depending on the need and application, each type has its advantages. Spray foam performs well, but it can be expensive and can cause serious damage to your home if it’s not installed properly.
Thoroughly fills cavities
Not as cost effective as other insulation types
Higher carbon footprint than non-foam insulators
Must be professionally installed
The Winner: Blown-In Cellulose Insulation!
At Sustainergy Cooperative, we recommend blown-in or dense-packed cellulose insulation for most projects. Cellulose is one of the safest and most effective insulation materials and it’s also one of the most affordable.
However, every home is different! We will conduct a free energy assessment at the beginning of your insulation project, during which we will consider your home’s design, your needs, and your budget. All of our recommendations are based on building science principles, not sales tactics. We are a worker-owned company which allows us to uphold the highest standards for quality. Our technicians are invested in the company—your success is their success!
