Is Fiberglass Insulation Ruined if It Gets Wet?

Fiberglass is an effective insulator that reduces the impact of outside temperature on indoor comfort in many homes. If used and cared for properly, it can last for a very long time.

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Insulation makes a big impact on the comfort of your home if used properly.

Water Absorption

Individual fibers in fiberglass insulation are made from sand and recycled glass, so they will not absorb water. Even if they get wet, the fibers themselves will remain structurally sound and functional.

Clean Water

When fiberglass insulation gets wet, the water actually replaces the air in the tiny spaces between fibers. Water conducts heat easily, so this will greatly reduce the insulating ability of the fiberglass until it dries out completely. However, provided that the insulation has not lost any volume in this process, it will work just as well as it originally did once it dries.

Dirty Water

If your insulation has become wet with water that is contaminated with foreign materials, such as sewage or dirty rain water, you should remove and replace the insulation. The contaminants could provide a base for the growth of mildew and mold, making your home unsafe or smelly.