According to CMHC, housing is affordable if it costs 30% or less of a household’s before-tax income.
However, different rental housing development programs and incentives make use of different definitions. Many consider affordable housing to be based on Average Market Rent (80% or lower). But we know that when housing prices far outstrip what households are earning, the “average market rent” model does not reflect what a household can afford in reality.
In contrast, if all households truly paid only 30% of their income on housing - whatever that income is - it could significantly reduce poverty, as housing is often one of the largest items in a household budget.
Further to that, if affordability also included other metrics like proximity to amenities, cost of transportation for work, and access to supports, it would be an even better reflection of what households can actually afford.