Gregor Robertson unveiled the details of Vancouver's proposed vacant home tax Wednesday, including who would be exempt from the steep levy. 

The mayor said the tax, if approved by city council, would be one per cent of an empty home's assessed value, which would amount to $10,000 on a $1 million residence.

"We have the lowest vacancy rate and the highest rents of any city in Canada right now," Robertson told reporters at a news conference. "People are feeling squeezed on all sides, so it's time to take action."

The tax, which will rely on owners self-declaring that their property has been sitting vacant, will only apply to non-principal residences, and several groups that were identified through public consultations will be exempt.

Those include homeowners whose properties are undergoing major and properly permitted renovations or redevelopment, and people who are in medical or supportive care.

Anyone who purchased their property the previous year will also be exempt, as will those whose homes are subject to existing strata rental restrictions.

Owners who use their property six months of the year for work but have principal residence somewhere else won't have to pay either.

Robertson said the primary purpose of the tax will be to boost the city's housing supply in the hopes of making it easier for people in need of a rental home to find one. The current vacancy rate sits at a record-low of 0.6 per cent. 

According to the city, there are at least 10,800 homes empty year-round in Vancouver, and roughly 10,000 more that are under-occupied.

"It's absolutely unacceptable for all that housing to be treated as a commodity first – as a business holding – when housing is in such short supply," Robertson said.

Vancouver's proposed tax, which would be the first of its kind in Canada, is expected to go before council next week, and the city hopes to have it in place by Jan. 1, 2017.