Get written estimates that spell out the tear-off, decking repairs, ice and water shield, flashing and ventilation, so you can compare them line by line. Ask for proof of insurance, the shingle manufacturer’s certification and the workmanship warranty in writing, and read recent reviews from homeowners near you. New Hampshire does not license roofers at the state level; in Massachusetts, confirm the contractor is a registered home improvement contractor and that a licensed Construction Supervisor will pull the building permit. We are fully insured, Owens Corning Platinum Preferred, MA HIC Reg. #212691 with Construction Supervisor License CS-120178, and every roof we install is backed by our 25-year installation warranty.