Someone asked me the other day how policy-makers could quickly respond to the housing affordability crisis in Metro Vancouver. My reply was my typical reminder that there is no silver bullet. But after I paused to think for a few seconds, I said the solution to our housing crisis is to enable every owner of a single-family home in Metro Vancouver to become a developer.

I went on to explain that the proper response to unaffordable housing is more housing supply and the best way to increase housing supply is to make more efficient use of land that is already developed for housing. The magic to doing that is doing it quickly, doing it across the region and doing it efficiently.

Most of the new housing supply that has been built in the last two decades has been multi-family housing, either low-rise and highrise condominium apartments or condominium townhouses, built on land that was converted from industrial or commercial uses or on "greenfield" sites - land that was either once farmland or rural vacant land. Relatively few new single-family homes have been added to existing single-family neighbourhoods.

Metro Vancouver will need to supply about 500,000 new homes over the next 15 to 20 years to accommodate population growth. Imagine if the land where Metro Vancouver's 300,000 or so single-family homes could be used more efficiently to deliver additional new dwellings. We could accommodate a big portion of that housing supply without big development projects and without developers.

Any new housing built as part of the redevelopment of single-family lots would also be ground-oriented housing as opposed to highrises, which makes that housing a lot friendlier to families.

Individual small redevelopment projects should also require less processing of approvals, meaning that the new housing could be supplied faster to meet market demand.

Here is how it could work.

Every Metro Vancouver municipality could change its single-family zoning regulations to permit more than one dwelling per lot. Vancouver and other municipalities already allow multiple dwellings in their single-family zones. In Vancouver, for example, almost every single-family zone allows a primary residence, a secondary suite in the primary residence and a laneway house. I propose that every single-family lot in Metro Vancouver over 5,000 square feet be permitted to have four dwellings and every single-family lot under 5,000 square feet be permitted to have three dwellings. I propose that these be outright uses, rather than conditional uses.

These additional dwellings should be allowed to be configured and designed in any form. Why does a laneway house have to be in a separate building? If one building can accommodate three or four dwellings, then that should be allowed. Performance-based criteria should be set to regulate the design. Rather than setting prescriptive rules about height, density, set backs, building form, etc., municipalities could set performance standards that deal with issues like shadowing, overlooking adjacent properties, privacy, access, tree retention, building shape, etc.

To streamline the approval process for this kind of redevelopment - remember, we would not be dealing with developers, but homeowners redeveloping themselves - design reviews could be done by the applicant's own certified professionals, rather than by planners at city hall. Architects are certified professionals and design experts who are obligated to uphold industry standards and comply with regulations. They could be the ones to judge whether the design meets the performance requirements. This would significantly reduce costs to government and speed up getting new housing supply to the market.