We’ve started a bathroom remodeling project. The home was constructed in the early 1970’s and it was time for some updating of the two upstairs bathrooms. We pulled all the materials out of the first bathroom and had the mechanical and electrical work revised to accommodate the new fixtures. We expanded into a nearby bedroom a bit to create a walk-in closet.
It was interesting to see how air had passed through the exterior building insulation behind the acrylic shower stall. The home has 2×6 walls, but there was no vapor barrier installed behind the shower unit. When it was removed you could clearly see how air had been moving through the insulation, pulling dust from the home with it. The yellow insulation was discolored from the air flow. In these photos we have covered the old insulation with a new polyethylene vapor membrane and taped and caulked the seams and edges to prevent air flowing where it shouldn’t be flowing.
This shows how important it is to have a properly installed vapor film on the warm side of walls. If a home doesn’t have a vapor membrane the drywall finish can act as a membrane if it is treated with the proper paint finishes and sealed at all openings. However, when there is no drywall over the insulation, as in this instance, air can really rush through the insulation. In conditions like this the insulation is not doing its job at all.