Insulation Basics for Ohioans: Should You Choose Fiberglass or Cellulose?

Your heating and cooling equipment work hard to achieve comfortable, consistent temperatures inside your home, and insulation is an important collaborator in this process. Insulation provides a barrier to warm air escaping in the winter and entering in the summer. Many older homes and even some new ones may not be insulated to minimum building code standards. Inadequate levels of insulation result in higher energy costs. As a result, significant improvement in energy efficiency can be gained by installing insulation to the proper levels.

Blown-in insulation is effective for the corners and irregular spaces where pre-formed insulation is difficult to install. Fiberglass or cellulose are both available for blown-in applications. Here's a quick primer on these two popular form of insulation.


Fiberglass, made of sand and other materials spun into glass fibers, settles very little over time – less than 2 percent -- maintaining its R-value, or thermal resistance, indefinitely. It’s made from inorganic, non-combustible materials and is accepted by building codes as a fire stop. It has no corrosive effect on wiring or pipes.

Fiberglass insulation also doesn’t absorb moisture. When properly installed, it resists the moist, humid conditions that invite the formation of mold. It doesn’t provide a food source for insects either. Fiberglass has been extensively tested for safety and effectiveness, with positive results.


Cellulose is an organic product made from recycled newspapers and needs to be treated with fire-retardant chemicals; some chemicals in this type of insulation have the potential to corrode wires, pipes and fasteners. It also needs insecticide treatment. The material will hold moisture for a period of time before drying. Moisture also will tend to degrade its fire retardant properties. Cellulose needs to be installed to a thickness that compensates for a settling rate of about 20 percent.

For more expert advice about insulation and other issues related to home comfort, please contact us at Joe Behr Plumbing & Heating, Inc. We’ve been providing expert HVAC services for the Mid-Ohio area since 1965.

Our goal is to help educate our customers in the Mid-Ohio area about energy and home comfort issues (specific to HVAC systems).  For more information about insulation and other HVAC topics, visit our website.

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