Does the state of Michigan require a State GC License for commercial roofing repair? I see that Michigan does not have a law regulating commercial builders, but it also states a license is required for a project over $600 or more and unlicensed contractors face the first offense is punishable by a fine of $5,000 and $25,000, one year in jail, or both. Subsequent violations extend the jail time to up to two years. Specifically, do we need a State license to perform roof repair/alterations for a commercial customer.