The cost of building a new roof from composite hinges on the size and complexity of the roof, the type of composite roofing used, and labor costs in the area. On average, installing a new roof made of composite can cost anywhere from $5 to $12 per square foot. For an average-sized home with a 2,000-square-foot roof, this would range from $10.000 to $24.000, not including labor costs, which can vary from $2.000 to $5.000 or more.