Crawlspace Repair - Code Compliant,.... But does it do its job?

For over 20 years we have been inspecting crawlspaces in residences throughout Western Washington. Very seldom do we see a "code compliant" or maybe a better term might be "code minimum" below grade space that does not have issues. Those issues can range from water intrusion, settling posts and piers, rodent and vermin intrusion, mold and mildew due to high humidity and outside air flow, damp wood insects such as powder post beetles and carpenter ants, and failing insulation and ground covers that were installed and approved by local building officials.

 Today I want to focus a bit on fibreglass batt insulation that is typically installed between the floor joists and held in place by a combination of friction and something to support it from falling out of the joist bay such as twine, wire stays, or wood lathe. This is not ideal for many reasons, but seems to be about the best they can come up with to be able to use this relatively inexpensive product. Fibreglass is a wonderful product when used as designed which is in a six sided enclosed cavity. In that application it can attain its full R Value and is a cost effective for wall and a floor system that would be fully filled and enclosed. Sadly that is hardly ever the case with our typical floor system.

 What we more often than not see is insulation that does not fully fill the cavity, gaps between the insulation and the floor that render it virtually useless as it then loses its insulation value, falling insulation, insulation being used as nesting areas and bathrooms by rats and mice. It also holds moisture from excess humidity and outside air in the crawlspace which causes it to become heavy and start to fall from whatever system was supporting it when it was dry and first installed.

 If only from an energy saving and sustainability perspective there are much better ways to construct and/or repair below grade spaces. It is truly a shame that we have to bag and transport thousands of feet of fibreglass insulation to the dump every year. But making your below grade space healthy, dry, and energy efficient is what we do.