Wet wall insulation

Wet wall insulation.

Residential homes in Canada are required to have proper insulation installed in wall cavities. With the exception of custom built homes it is usually a fiberglass batt type insulation.  As time passes this insulation may become wet. There is a number of reasons as to why this insulation may become wet. I will review a few of these reasons here.

In the residential houses we can usually find insulation in the following  areas: attic or flat roof, main walls and foundation walls.

Attic insulation. This insulation may become wet from a number of reasons. One is the obvious and it's a roof leak. The other reason, which is not so obvious, is a condensation. Condensation occurs when warm conditioned air from the living space gets into the attic and condenses on the cold  surfaces, such as framing or roof deck. That is why it is very important that exhaust fans from the kitchen or bathrooms will be vented to the exterior rather than left in the attic.

Main wall insulation.  This insulation may become wet from plumbing leaks or from exterior infiltration. In the wood frame house construction it is important to have weeping holes of the proper size and at the proper location. More often than not these holes become plugged by the homeowners that don't understand their importance. These little holes act as vents for the entire wall system and should always be clean and unobstructed.

Basement insulation. The most common reason for wet insulation in the basement is flood or exterior water infiltration. It is important to have foundation cracks sealed along with proper grading and drainage of the exterior surfaces. The back flow preventer valve needs to be installed inside of the house to protect basement from sewer back-ups.

So what happens when the insulation becomes wet? Fiberglass insulation works by trapping air bubbles between the fibers  thus providing a barrier for heat to escape. Wet insulation looses these air bubbles and becomes a conductor rather than insulator. It loses its insulation R-value to almost zero. If there is a possibility to dry the batt insulation out then it can be reused, however its R-value will never be the same. And because insulation is not very expensive it can be easily replaced, especially in the open areas, such as attic. It is different when insulation becomes wet in the wall. In this closed space insulation cannot dry quickly enough and may start growing mold. It may take long time until the first signs of wet insulation behind the drywall will show up, and by this time it maybe too late. Mold spores can thrive and deteriorate the indoor air quality. This in turn may cause significant health issues, especially in people with asthma or those that have a compromised immune system.

Wet insulation can be detected by infrared thermal imaging scan long before it will cause substantial damage. A proper infrared inspection may allow to identify suspected areas early enough to avoid costly remediation. Structural integrity of your house, its energy efficiency and your health are much more important than the cost of the infrared thermal imaging inspection.

Call us to book your IR inspection today at 416-909-6467.