Crawlspace Insulation
in Metrotown, BC

The Metrotown area of Burnaby is predominantly high-density residential and commercial development, but the surrounding streets include significant numbers of older single-family homes and low-rise residential buildings on crawlspace foundations. These homes — largely from the 1950s through the 1970s — occupy the relatively flat terrain of central Burnaby, with clay-loam soils and drainage conditions typical of the region.

The majority of homes in Surrey and the surrounding communities built before 2000 have fiberglass batt insulation installed between the floor joists in the crawlspace. When this insulation was new and dry, it provided reasonable thermal resistance. The problem is that fiberglass batts installed in a vented crawlspace environment in a high-rainfall climate like ours rarely stay dry. They absorb ambient moisture, sag out of their cavities, and gradually collapse onto the ground. Wet fiberglass insulation has essentially zero R-value, adds weight that can pull down on vapor barriers or staples, and provides a hospitable nesting environment for rodents.

For crawlspaces that are not being fully encapsulated, we install new unfaced fiberglass batts or mineral wool between the joists, but only after addressing the moisture conditions that destroyed the previous insulation. Installing fresh batts into a still-damp crawlspace environment means you'll be back in the same situation within a few years. Proper sequencing matters: drainage, vapor barrier, then insulation.