This article is from the Model Rockets FAQ, by Wolfram von Kiparski with numerous contributions by others.
At the present time, A-G powered model rockets, with launch weights up to
one pound, are legal to fly in most parts of Canada. H powered rockets and
up, as well as rockets weighing more than one pound at liftoff, are
considered 'High Power.' HPR launch sites require certification by
Transport Canada. HPR certification is done by CAR.