This means big savings for both building tenants and homeowners alike. It can happen quickly, too. Under the proper conditions, established English Ivy can grow to cover an area of roughly 500 square feet per year. Given that most homes have a roof measuring roughly 2000 square feet, ivy-friendly homeowners can rest assured that their roofs will be completely covered in about four years. When considering growth rates of newly planted ivy, just remember the old adage: First year, it sleeps. Second year, it creeps. Third year, it leaps! For English Ivy, this is especially true.