Lavoie, a 22 year-old from Quebec City, was perfect in his fifth of six games on the day, helping Canada reach a total score of 5,607 — 318 better than second-place Colombia. The United States took the bronze medal.
MacLelland nearly threw two perfect games himself Thursday, but the 30 year-old from Kitchener, Ont., lost them both on the last few rolls.
Lavoie said he'd savour the gold medal.
"That's just the cherry on top," he said. "To do that anywhere is great, but to do it here when everyone was here, including my parents, that's cool. It's indescribable. I don't really have any words to say."
Lavoie and MacLelland will also compete in the men's singles event Friday.