Before you Start your Project

Now that you have selected a professional contractor, insist on the following before the work begins on your roofing project:

Get it in writing. Insist on a written proposal
   and make sure it contains:

Complete specifications and full and accurate descriptions
  of the work to be done.
Approximate start and completion dates.
Agreed price and payment procedures.
Plans for prevention of landscape damage and cleanup and
  disposal of roofing debris.
A warranty covering workmanship and proper installation of
  your roofing system.

Talk it over. Discuss your project and make sure you are
   Comfortable with:

Project supervision and quality control procedures.
The person who will supervise the project. Make sure to get
  their name and phone number. Will they be available to speak
  with you during the course of your project? Know your
  responsibilities.
If you choose to buy roofing materials direct from the
  manufacturer, you will be working with two different parties.

Dividing responsibility between a manufacturer and installer increases
   the likelihood of problems during installation. You may encounter
   issues such as:

Incompatibility of materials, difficulties with on-site job
  coordination, additional safety considerations, and specific
  warranty obligations.