At CMHC we have done some long-term demographic projections. These are based on census data.
We look at cohorts over time and how their demand for housing evolves. From what I can remember, going out as far as 2020 or 2030, there's still an ongoing demand for more housing. Even if the population is aging, the number of units continues to rise. A big reason for this is immigration, where there continue to be large inflows. That offsets it and contributes to the demand.