The average cost to replace a roof on a 3,000 square foot house using a professional roofing company can cost from $11,000.00 to $17,000.00 which includes the tearing off of the old shingles, cleaning it up, adding new roofing felt and then the new shingles.
A 3,000 square foot house may require at least 2 days from start to finish even for a professional roofing contractor with several roofers doing the job.
A friend has a 3,000 square foot house and it took the crew two days to tear off and replace the roof and it cost him $13,000.00 but they did a great and fast job.