In a surprise move Thursday night, council voted to protect 303 potentially significant heritage buildings in the heart of downtown from demolition for a year.

After the walk-on motion from Councillor Joe Cressy (Ward 20 Trinity-Spadina) passed 30 to 1, demolition of those buildings within the King-Spadina neighbourhood, which stretches from Richmond St. West to King St. West and from Bathurst St. to Simcoe St., can be rejected by city staff.

“We’re at risk of losing the city’s heritage as we grow if we don’t move quickly to protect these historic buildings,” Cressy said. “It stops the wild-west demolition practice of demolishing buildings that have heritage value which we have not yet designated.”

The protection comes in the form of a rarely used heritage conservation district by-law allowed under the Ontario Heritage Act.

King-Spadina is the fastest growing area in the city. The population has increased from just 945 people in 1996, when the area was largely industrial, to 19,000 people in 2016. New development is expected to see the number of people and employees reach 50,000 each.

For three years, city staff have been carrying out a study of the area’s heritage, which is expected to be completed next year.

Without the controls enacted Thursday, staff were unable to block demolition if an applicant followed the rules of the process.

With the new controls, any buildings that were already slated for demolition can be brought down and alterations will still be permitted.

“Over the course of the past several months, there has been an acceleration of demolition permits to demolish buildings that are contributing to the heritage character of the area,” said chief planner Jennifer Keesmaat.

Four buildings that could have been designated as heritage properties have been demolished since the study began, Keesmaat said, and applications for demolition permits have already been submitted for another 10 properties.

Council’s decision can be appealed to the quasi-judicial Ontario Municipal Board which deals with most land and planning disputes, but those appeals could take months to get to a hearing.