The province has strengthened the rules behind balcony glass used in new building construction after a spate of glass panes fell and shattered in downtown Toronto.

The Ontario government said on Thursday that it had changed the Building Code to require construction companies to use heat-strengthened laminated glass near the edges of a balcony.

It is the same kind of glass used in windshields and is less prone to shatter than the type most commonly currently used.

Construction companies will also need to use heat-strengthened laminated glass or heat-soaked tempered glass when glass balcony guards are inset from the balcony edge.

The change was a recommendation made by an advisory council and comes after several glass panes fell from Toronto high rises. The new rule with be enforced on any construction beginning as of July 1.

"This amendment will help protect the public and offer clarity and certainty to the building industry," Kathleen Kynne, Ontario's municipal affairs and housing minister, said in a statement.

"I'm thankful to the members of the expert advisory panel for their contributions and sound advice."

Last week, a pane of glass fell from the 25th storey of a Toronto condominium tower on Simcoe Street, near Richmond Street West and University Avenue.

It was the fourth recent incident in which falling glass shattered in the downtown core.

Glass panes have also fallen from the RBC Centre, a Queen Street condo tower and the Trump International Hotel and Tower.

No one was injured in any of these incidents.