Buying a new roof system is an important investment. Before you spend your money, spend some time learning how to evaluate the roofing contractor who may be doing the work. You should insist on working with a professional roofing contractor. The National Roofing Contractors Association (NRCA) wants to assist you in getting the kind of results you expect -- a quality roof system at a fair price.

All roofing contractors are not alike, and NRCA recommends that you prequalify roofing contractors to get the job done right the first time. The following guidelines will help in your decision:

• Check for a permanent place of business, telephone number, tax I.D. number, and where required, a business license.

• Insist on seeing copies of the contractor's liability insurance coverage and workers' compensation certificates. Make sure the coverages are in effect through the duration of the job.

• Look for a company with a proven track record that readily offers client references and a list of completed projects. Call these clients to find out whether they were satisfied.

• Check to see whether the contractor is properly licensed or bonded. Call your state's licensing board for your state's specific requirements (where applicable).

• Insist on a written proposal and examine it for complete descriptions of the work and specifications, including approximate starting and completion dates and payment procedures.

• Check to see if the contractor is a member of any regional or national industry associations, such as NRCA.

• Call your local Better Business Bureau to check for any complaints that have been filed.

• Have the contractor explain his project supervision and quality control procedures. Request the name of the person who will be in charge, how many workers will be required and the estimated time of completion.

• Carefully read and understand any roofing warranty offered and watch for provisions that would void it. Keep a healthy skepticism about the lowest bid. If it sounds too good to be true, it probably is. Remember, price is only one criterion for selecting a roofing contractor. Professionalism and quality workmanship also should weigh heavily on your decision.

NRCA offers an automated toll-free telephone number, 1.800.USA.ROOF (872.7663), to help homeowners locate professional roofing contractors in specific geographic areas. Callers are sent, free of charge, a computerized list of NRCA-member contractors sorted by zip code and type of work (commercial or residential), a listing of local and regional NRCA affiliate organizations and a booklet that describes common roofing systems and general roofing terminology. Information will be sent within three weeks of the date of your call.