Roofing contractors don & usually need formal education, but they require on-the-job experience to discover their trade. While each state has various licensing guidelines, a lot of need a roofer to have at least two years of experience prior to they can become certified. These experts also require liability insurance, to be bonded and to have a service license. HomeAdvisor can assist you find the ideal roofer for your project. While each state has different licensing rules, a lot of need a roofing professional to have at least two years of experience before they can become certified. These professionals also need liability insurance coverage, to be bonded and to possess a service license.