My kitchen is next an exterior wall of my house. Unfortunately there is a constant flow of cold air coming from underneath the cabinets into the kitchen itself.
Here is a picture of the cabinets:
After taking a closer look, I realized that there is a 1" gap underneath the cabinets that seemed to be the source of the issue:
My guess is that the gap was left there because of the vent, but it's making the floor (and that whole area of the home) very chilly.
What is the best way to safely fill the gap (given the nearby vent) and prevent the flow of cold air?
Best Answer
Usually cabinet makers don't try to seal the gap between the toekick and the cabinet box. What's most likely happening is there is an opening in your drywall behind the cabinets for plumbing or electrical that the installers did not seal, and that is your source of cold air.
Since getting to that is near impossible (without dismantling the cabinets) your're going to have to settle for plugging the gap. Maybe some fiberglass cut to fit, and some plastic tape to seal. The space under that cabinets may run the whole length of the assembly. It will be a kludge no matter what. Just make it look semi-reasonable.
That register; is it a return or a supply? A return may just come up in the floor, and they cut the toekick to provide flow. A supply should be ducted to the register cover.