It depends on the type of roofing material. For example, asphalt shingles usually last about 20 years, while slate and tile roofs can last up to 100 years. Most roofing materials come with a warranty that covers replacement after a certain number of years. If you're not sure when your roof was last inspected or repaired, it's best to err on the side of caution and have it inspected at least once every five years. Professional roofers can look for signs of wear and damage that may indicate a problem down the road.

It's generally recommended that homeowners have their roofs inspected every two years. However, depending on the condition of your roof, you may need to have it inspected more or less often. If you're experiencing any problems with your roof (e.g., leaks, missing shingles, etc.), then you should have it inspected as soon as possible.