Cost-Effectiveness of Increasing Airtightness of Houses

In a cold climate such as of Montreal, the air infiltration through the exterior envelope of a house has a significant impact on the heating energy consumption and cost. The renovation of existing houses for increasing the airtightness up to the level of new, well-built houses can lead to the reduction of heating energy cost. This paper estimates the cost-effectiveness of this type of renovation by considering (1) the life-cycle energy consumption; (2) the initial cost of renovation; and (3) the CO2 tax credits, which take into account the environmental impact of increasing the airtightness of existing houses. The results show that the increase of airtightness of existing houses is not always cost-effective in the Montreal area.