Rating Newest Oldest. Best Answer: About 15-20 years for the standard asphalt shingles. You can pay more to get some that are supposed to last longer though. I live in Florida too and we replaced our roof when it was about 16 1/2 years old. It also depends on if there is a lot of debris on your roof, or if you keep it cleaned off. If there is a lot of debris up there it keeps the shingles wet after it rains and they will deteriorate faster.