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The Reliable

Fiberglass Insulation Pros and Cons

Fiberglass Insulation Pros and Cons

A long-standing option for resisting heat transfer in Atlanta-area homes, and in homes across the country, fiberglass insulation was developed in 1938 by a researcher named Dale Kleist, notes InterNACHI. The go-to insulation choice gave homeowners a low-cost way to insulate their homes — the material was widely available and it was easy to install.

But advancements in insulation technology has led to the dethroning of fiberglass products. While it still holds some advantages, it also poses a few distinct challenges, too.  Listed below are fiberglass insulation pros and cons.

What Is Fiberglass Insulation?

The insulation is manufactured using tiny fibers of glass spun at an extremely hot temperature. It looks much like cotton candy, but the fibers are packed together to create rolls, or batts, of insulation.


A few of the advantages the insulation offers include the following:

  • Easy installation: The rolls or batts are manufactured to comply with standard joist width builders use for walls and floors. As a result, they are very easy to unroll inside the joists.
  • Moisture resistant: One important way insulation must perform is resisting moisture that may penetrate through the roof or humidity in the air. Fiberglass products do a great job of resisting moisture, so builders often choose to use it in higher-humidity regions. Because it can resist moisture, it is less prone to mold growth, which some other insulations are known for.
  • Noncombustibility: The material is noncombustible, or fire resistant, which is important for a material installed next to the home’s wood structure and for general household safety.
  • Renewability: Almost half of the material is recycled, and the other portion of the insulation is manufactured from sand, which is renewable.


In spite of its advantages, homeowners should also consider its downfalls:

  • Improper insulation reduces efficiency: Even though it’s easy to install, the insulation’s performance can decrease dramatically if it’s not installed properly. Gaps in the layers of insulation can drive down performance, as the gaps allow heat movement in between the insulation.
  • A lower efficiency overall: Comparatively speaking, fiberglass products don’t rate as high as some other insulations in terms of resistance (or R-value) per inch. In addition, when temperatures fall, the product loses performance value.
  • Energy hogging. To produce the insulation, manufacturers have to use a lot of energy, and the process releases a good deal of air pollution compared to other manufacturing processes for insulation types.

Other Options

If you’re not convinced that fiberglass is the way to go, talk to your contractor about other options. Cellulose is manufactured from recycled newspaper, and the blown-in form fills in spaces well, creating a tight seal. However, the material also takes on moisture more easily than fiberglass.

The best way to choose insulation involves discussing the options with an expert, carefully evaluating the cost-benefit ratio and risks and then choosing a product that fits your budget. For expert advice when choosing insulation, contact Reliable Heating & Air today! Reliable offers both blown-in fiberglass and cellulose insulation and can help you determine the best product for your home.