Grand Rapids - Kalamazoo - Muskegon - Grand Haven - Holland

Cellulose vs. Fiberglass Insulation

R-Value & Air Infiltration

While cellulose and fiberglass insulation have comparable R-values, cellulose insulation has one major advantage, the reduction in air infiltration.  Cellulose insulation reduces the amount of space in a cavity, effectively sealing any gaps where air can travel.

These gaps are a significant factor in energy loss.  In fact, some studies indicate that cellulose insulation can prevent 20% more energy loss than fiberglass due to its superior ability to reduce air infiltration.

The ability of cellulose insulation to reduce air infiltration raises its “Effective R-Value” to levels far exceeding that of traditional fiberglass insulation.

Studies have also indicated that fiberglass insulation may lose some of its R-value as the outside air gets cooler, while cellulose shows little change.  This makes cellulose insulation a great choice in climates where extreme cold is common.

Environmental Impact

Nu-Wool cellulose insulation is manufactured using 100% post-consumer recycled paper.  Additionally, it is manufactured using at least 10 times less energy than it takes to make fiberglass insulation. Nu-Wool offers green benefits even before it’s in your walls!


The initial investment in installing cellulose insulation is generally higher than traditional fiberglass insulation; however, Nu-Wool cellulose insulation provides up to 40% savings on energy bills when compared to conventional insulation materials and offers homeowners the best value and return on investment.

Health Concerns

Toxicologist studies demonstrate no observed adverse health problems associated with Nu-Wool Premium Cellulose Insulation.  Conversely, fiberglass insulation can cause health issues when inhaled.  Extreme caution must be taken when installing fiberglass insulation or when fiberglass insulation has been disturbed after installation.

Fire Rating

Nu-Wool Premium Cellulose insulation is a Class 1 fire rated product, and should a fire occur, the dense structure of cellulose and its fire retardants will slow the spread of the fire through the building by blocking flames and hot gases and restricting the availability of oxygen in insulated walls and ceilings.

Mold & Mildew

Nu-Wool Premium Cellulose Insulation is one of the few insulation products that contain a fungicide registered by the Environmental Protection Agency (EPA). 

Excess moisture is the root cause of all mold growth. Since moisture is transported through the movement of air, cellulose’s inherent ability to block airflow reduces the likelihood that adequate moisture levels will permeate the insulation.

Furthermore, the superior moisture management properties of Nu-Wool Premium Cellulose Insulation actually make it a better choice than fiberglass insulation for managing moisture problems. Nu-Wool absorbs moisture, redistributes it, and lets a wall dry in a controlled manner. If a leak does occur in a wall insulated with Nu-Wool Premium Cellulose Insulation, the likelihood of the insulation remaining wet is far less than with fiberglass insulation.    

Acoustic Performance

Cellulose insulation is acoustically superior to traditional fiberglass insulation due to its ability to limit or stop air infiltration.  Sound is carried by air, when sound has no vehicle to travel it is effectively dampened.