The cost to replace a roof on a home is highly variable. It depends on the size of the roof (how many square feet), the pitch of the roof (the angle of the steepness), how high up the roof is (one, two, or three story home, and what type of shingle is being installed. Each estimate is custom to the house and the desired products. That said, the average roof replacement is between $8,000 and $15,000. It is a big range of course, and some roofs are less ($5,000 for example) and some very large roofs can be much more ($25,000 to $80,000 ). Because the cost is highly variable, Dr Roof offers free estimates for new roof installs.