Safe. Proven.

... and you can pronounce its ingredients.

Fiberglass Insulation – It’s an easy decision

Get the facts about fiberglass

Whether you’re remodeling your home or building a new one, you have a mind-numbing number of decisions to make. With everything you have to think about, what’s going inside your walls – where no one will see – is probably not near the top of your list. But it should be, because you only have one chance to do it right.

With many insulation contractors, you have two options: fiberglass or spray foam. Both have their proponents, but fiberglass has advantages that make it an easy decision.

Breathe easy

The truth is, fiberglass meets high standards for comfort, efficiency and value, and it does so with safe, mineral-based ingredients.

Once you get the facts about fiberglass, you’ll want to have a little chat about it with your builder or contractor.

Why is fiberglass a smart choice?

Proven Performance

Fiberglass insulation has a 75-year track record for performance, and ongoing technological advances continue to yield products that perform, are safe and – like blown-in systems – are truly innovative.

Proven Performance

Familiar Ingredients

Fiberglass insulation is made primarily from familiar ingredients – not from petrochemicals – and fiberglass installers don’t need supplied-air, hazmat-looking suits.

Proven Performance

Superior Value

R-value is the measure of insulation’s thermal performance, and it’s independent of the type of insulation: R-13 fiberglass insulation provides the same comfort and energy efficiency as R-13 spray foam. That makes fiberglass – which costs less – a more cost-effective way to achieve the comfort and energy efficiency you want. Spray foam may tout its higher R-value per inch, but when it comes to your wallet, isn’t R-value per dollar more important?

Proven Performance


When it comes time to make repairs or changes to plumbing and electrical lines, having fiberglass insulation makes the job much easier – no need to chisel out hardened foam.

Proven Performance

Percentage of new homes built with fiberglass insulation1

Miles of glass fiber one recycled bottle can turn into2

The average return on investment for adding fiberglass insulation to an attic3

Fiberglass insulation has known ingredients

Put simply, fiberglass is just another form of glass. Its ingredients – and there are only six of them – are similar to those in the bottles and jars we use every day. They’re just spun into fibers instead of being blown or molded to make containers.

NAIMA Fiberglass Wave

Here are the six simple but highly effective ingredients of unfaced fiberglass insulation:1

Crushed Glass

Crushed Glass

Also called glass cullet, crushed recycled glass is now the main ingredient in most fiberglass insulation products. As more recycled glass becomes available, fiberglass insulation will contain even

Crushed Glass


Natural and abundant, silica sand is the primary ingredient in virtually all types of glass. Because the availability of recycled glass is limited, it must be supplemented with fresh sand and other

Crushed Glass


Borax, a naturally occurring compound of boron, is formed by repeated evaporation of seasonal lakes. It’s commonly used in laundry detergents, soaps and

Crushed Glass

Soda Ash

Soda Ash is a trade name for sodium carbonate. Like borax, it is a natural, evaporite mineral mined from dry lake beds around the world. It’s a common ingredient in many products, including soaps and detergents.

Crushed Glass


Limestone is a sedimentary rock that makes up about 15% of the Earth’s crust – there’s lots of it out there. It has many uses, including the manufacture of paper, plastic, cement and carpets, as well as in the processing of various foods and

Crushed Glass

Binder Coatings

Binders allow fiberglass to retain its shape. Today, plant-based binders derived from sugars and starches have replaced older formaldehyde formulations.66Data obtained from NAIMA members

1 Percentages are based on a generic, R-13 unfaced fiberglass batt.





6 Data obtained from NAIMA members

Get the real scoop on insulation

Sure, the Internet contains a wealth of information – and misinformation, dated information and hype, particularly about spray foam. When researching the safety of products being installed in your home, it’s best to trust authoritative sources, such as government agency sites. Here are a few good resources to help answer other insulation questions you may have.

It’s time to contact your builder/contractor

There’s a pretty good chance that your builder or contractor won’t raise the subject of insulation with you if you don’t.

Email them today and let them know you want fiberglass insulation. We’ll help you get the conversation started by sending an email to them for you, or you can download the information on this page and take it with you to your next meeting.

Email my builder/contractor

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The Insulation Institute is the educational arm of the North American Insulation Manufacturers Association (NAIMA). Our mission is to empower homeowners to make informed insulation choices.