Adfreezing of insulated residential basements: an hypothesis

Abstract

Concern has been expressed that recent increases in thermal insulation levels of residential basements in areas of seasonal frost may increase the risk of damage to foundations due to frost heave and adfreezing of the soil to the foundation wall. An hypothesis is presented which states that the adfreezing bond strength is affected by the direction of soil moisture movement in response to thermal gradients. This hypothesis may be used to explain why there have been no reported adfreezing problems associated with heated, insulated residential basements. Key words: adfreezing, basement, frost heave, insulation, moisture.

Towards Development of a 1980’s Greater Hamilton Area Single Detached Residential Housing Archetype: Retrofitting to the Performance Levels of Net Zero Energy Ready

“…The mineral wool insulation allows for outward drying of the assembly when an impermeable membrane is used on the interior. As the mineral wool insulation cannot protect the assembly against an inward vapour drive the presence of a ventilated air cavity behind the cladding reduces the chance of the wall getting wet (Pressnail et al, 2003). to the increased insulation levels in the building enclosure, the decrease in air leakage, and the efficiency of the mechanical systems was much better.…”

Measure Guideline. Hybrid Foundation Insulation Retrofits

“…Again, the phenomenon is dependent on freezing direction: heat loss from the foundation to the soil results in no or minimal adhesion, while heat flow from the soil to the foundation results in formation of a frost-adhesion bond. Therefore, adfreezing can occur in unheated structures (e.g., unheated garages, pier foundations), but it will not occur in heated (and insulated) foundations due to the outward heat flow (Pressnail 1987). …”