The answer to 'when to replace asphalt shingles' is that you typically need to replace asphalt shingles every 15-25 years, depending on the quality of the shingles and the climate conditions. Asphalt shingles are one of the most common roofing materials, and they have a finite lifespan due to weathering, sun exposure, and other factors.
Signs that your asphalt shingles need to be replaced include curling, cracking, bald spots where the granules have worn off, and leaks in your roof. If you notice these issues, it's best to have a professional roofing contractor inspect your roof and provide recommendations on whether a full replacement is needed.