In addition to the standard felt paper there are new types of underlayment. Some manufacturers reinforce the underlayment with fiberglass to strengthen and resist tearing, make installation easier and improve its waterproofing effectiveness.
Manufacturers are constantly developing new underlayments. Newer synthetic underlayments further increase the effectiveness of and ease & safety to install underlayment and increase longevity. Some manufacturers have developed organic and green underlayment products.
It is usually recommended to use underlayment from the same manufacturer as your shingles as they are designed to work together and it may be required for a valid warranty.
A contractor will choose the best type of underlayment for your roof replacement based on the type of roof and climate in which you live. If you have any questions regarding their choice, they are the best resource for your specific project.
Craig Gouker Roofing has been installing quality residential roofing in South & East Pittsburgh since 1991 and is the expert in shingle roof replacement.