Should Wet Insulation Be Replaced?

Loss of Thermal Protection

• Insulation slows the transfer of heat in and out of buildings by trapping tiny pockets of air within a dense matrix. Since static air is a poor heat conductor, insulation in good condition keeps the inside of your house cool in the summer and warm in the winter. When insulation becomes wet, those pockets of air are replaced with water, and the insulation loses much of its ability to resist heat transfer, since water is a significantly more efficient heat-transfer medium than air.

Moisture Retention

• There is very little air circulation and therefore very little drying potential inside your home’s wall cavities. Excess moisture inside your walls will soak through and damage interior drywall and wood paneling. Water pooling on interior wall footers will damage carpeting and trim as well.

Mold

• Mold grows best in dark, moist environments. According to the “Get Rid of Mold” handout distributed by the Centers for Disease Control and Prevention, “Things that have stayed wet for two days have mold growing on them even if you can’t see it.” Some types of mold are toxic and can cause adverse health effects.

Remediation

• Remove wet insulation as quickly as possible. Drying out wall and attic spaces before water damage occurs can prevent the damage from spreading to surrounding areas as the water soaks into drywall and wood framing. Allow any damp areas to dry thoroughly before installing new insulation. If the insulation has been damp for two days or more, wear rubber gloves, goggles and an approved mask when handling the insulation and related material.