After assessing the job, the contractor will determine the compass and conditions of the design. Grounded on the compass, the contractor can plan phases or assign crews to do the work. These services can be veritably important for several reasons, including the fact that a roofing contractor is frequently necessary for certain types of rainfall.
Source: https://globalblogging.com/what-are-the-essential-services-of-a-roofing-contractor/