Most governments require roofing contractors to be licensed through their state and fully insured. Find out what type of licensing is needed for your project on your local city, county or state website, and then choose a roofing contractor that fulfills those regulations.
Your contractor should also be able to provide you with a letter of coverage from an insurance provider for both liability and workers’ compensation insurance. That way, you’ll be protected if any issues come up while the roofing work is being done.
Contractors sometimes hire subcontractors to help complete roofing work. Be aware of who might be working on your home, and whether they meet the same certification requirements and have insurance to cover every employee. Ask your contractor about this and who you can contact if any questions arise. Any reputable contractor will welcome your questions and try to answer them as clearly as possible.
There are contractors out there that will tell you that you should just shingle directly over the old roof. That doesn’t mean they are bad contractors or trying to pull one over on you. It does save time and money. However, it is only by removing the current roofing materials that your contractor can see if there is any damage to the underlying boards. You might also consider adding a drip edge/edge metal and metal flashing to help protect your home from water damage in the future.
Removing a roof is messy business and a professional roofing contractor will already have procedures in place for dealing with that while also protecting the rest of your home. Ask your contractor if he or she has a container for the debris or if it is your responsibility to provide one. Have the answers written into your contract, specifying that any open areas will be properly covered with a tarp and that all the shingles and nails removed will be properly disposed of before the crew leaves for the day.
All the materials that will be used on your roof come with warranties from the manufacturer. Be aware that they do not cover any potential issues that arise if the materials are improperly installed. A qualified contractor is usually happy to back up his or her work with at least a one-year warranty.