Crawlspace Insulation
in Brentwood, BC

Brentwood is one of Burnaby's most actively developing neighbourhoods, with rapid densification around the Brentwood Town Centre SkyTrain station transforming what were single-family residential streets into a high-rise urban district. Beneath this transformation, however, there remains a significant inventory of older single-family homes on crawlspace foundations in the surrounding streets — homes that were built in the 1960s and 1970s and have not had major crawlspace work since original construction.

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.