My friends at 360 IRC has been one of the best roofing companies in Dallas for over a decade now.  While they handle residential insurance claims and can assist with roof repair and basic maintenance, they now specialize in Dallas commercial roofing and large scale flat roofing and metal jobs. They are one of the few companies in the DFW area who can handle these large jobs, making them a total roof company.  My son has even done bids on commercial roofing in Dallas for them in the past and highly recommends their great work.  I'd recommend anyone in the area take a look at what they have to offer, compare pricing and general expertise and give them a call, I've never seen them do a bad job and their work speaks for itself.  Their sister site provides custom roofing in Fort Worth and uses top-notch roofing contractors on every job.  We had our old house in Richardson, TX inspected for free and they found all sorts of bad stuff that needed to be rectified.