Do you need a permit to erect a 64 sq. ft. backyard garden shed in vaughan, Ontario?

You should check with your local building inspector. He'll be glad to tell you if you need a permit. There is also the question of location in relation to property lines, etc.

Do you need a permit to erect a 64 sq. ft. backyard garden shed in vaughan, Ontario?
No, but you do need one if it is any more than 27%.