1 While most asphalt shingle installation includes the removal and disposal of existing shingles, if this phase of the project is not included in the price, it might cost an additional $1 to $4 per square foot. 2  Metal roof installation costs around $5 to $15.00 per square foot or more.etal roofing, typically made from coated aluminum or steel, costs approximately one-third more than asphalt shingle roofs, but with the price increase comes a number of benefits. First and foremost is the strength and durability of metal roofs, which are often guaranteed for 50 years or more.