The answer to 'my roof is failing' is that there are several common causes, including age, weather damage, poor installation, and lack of maintenance. Symptoms can include leaks, missing or damaged shingles, sagging, and moss or algae growth. Solutions range from simple repairs to a full roof replacement, depending on the extent of the damage.
If the roof issues are minor, such as a few missing or damaged shingles, you may be able to handle the repairs yourself with the right tools and materials. However, for more significant problems like leaks, structural issues, or widespread damage, it's best to call in a professional roofing contractor to properly assess the situation and provide the appropriate solution.