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The Environmental Offer: A Look at Energy-Saving/Green Synthetic Roof Underlayments

What roofing contractors, builders and architects need in a slow market is a way to differentiate from the competition-for next to nothing. When comparing the payback of "old technology" asphalt-based roofi ng felts and SBS-modified asphalt underlayments versus synthetic underlayments, the first hurdle is to believe there are synthetic roof underlayments available that offer green and energy-saving benefits while improving the overall roof system. That is, provide the roofing contractor, builder and architect with an opportunity to offer their customers real long-term value and protection in their roof system, energy savings and potential LEED credits while offering products that are environmentally friendly.


What Makes Green?

Synthetic roof underlayments are available that combine the benefits of a radiant barrier, adhesives with no VOCs and are made from polymers that are recyclable. Some examples include: a recyclable synthetic roof underlayment that reflects solar radiation, enabling the reduction of the energy required for cooling in summer months (air conditioning); superior synthetic peel-and-stick roof underlayments that provide long-term moisture protection by providing a secondary water barrier in hurricane and high-wind prone areas; and mechanically fastened synthetics that are recyclable, provide long-term value and moisture protection to the system, have minimal impact on landfills and contribute to improved building envelope construction.

Synthetic roof underlayments are also available that function as a long-term moisture and vapor barrier, as well as provide a dried-in condition if the primary roof covering is damaged because of high wind or penetrated by wind-driven rain as with hurricanes and and other extreme weather events.

From the Washington, D.C.-based U.S. Green Building Council's "LEED for Homes FAQ for Builders," LEED measures green building performance based on seven categories, including Site Selection, Water Efficiency, Materials and Resources, Energy and Atmosphere, Indoor Environmental Quality, Location and Linkages, and Innovation.


Green Advantages

The advantages to the green building industry and to builders/roofing contractors and architects in general are the following benefits as they relate to the LEED categories of Materials and Resources and Energy and Atmosphere, as well as, depending on the overall building design, could impact the Indoor Environmental Quality and Innovation:

1. Radiant barrier synthetic roof underlayments provide long-term savings to homeowners by reducing energy costs.

2. A radiant synthetic combines a 100 percent recyclable polypopylene water barrier roof underlayment with a metallic radiant barrier (average emittance of 0.034). A 97 percent ultraviolet reflectivity greatly reduces the Heat Island Affect. This innovative combination results in high value for homeowners, improved efficiency for installation and competitive advantage for contractors.

3. Radiant barrier, self-adhered and/or mechanically fastened synthetic roof underlayments may allow architects and builders to reduce HVAC equipment requirements or add insulating benefits because of a reduction in cooling requirements and additional reduction in heat loss from the building envelope by adding R-value, respectively.

4. Self-adhered synthetic roof underlayments with no VOCs are recyclable and do not contaminate the environment. They out-perform traditional asphalt and SBS-based products adhesion value to substrates, provide UV protection, and combine the high tensile wind and tear resistant values of mechanically fastened roof underlayments while being lightweight and faster to install.

5. Lightweight synthetic underlayment rolls save warehouse space and transportation fuel costs. Rolls contain five times the surface coverage of standard tar-paper roof underlayments. This allows for ease of storage in a secure location on a job site and ease in loading and handling, potentially reducing workers' comp claims.

6. Long-term life-cycle cost savings-the durable synthetic underlayments out perform traditional tar-paper asphalt felt underlayments. Due to their long-life characteristics, negative impact on landfill space is minimal. Polypropylene underlayments are inert and will not decompose, leach out chemicals or outgas solvents unlike asphalt felts that contain petroleum processing byproducts and binders that will decompose over time. This means less energy spent on roof repairs and a benefit to the environment.

7. Synthetic roof underlayment products contribute to LEED points by providing lower operating costs; increased asset value; and, regarding risk management, reduced callbacks, thereby potentially reducing liability insurance rates while using environmentally preferred products.

Synthetic roof underlayments represent superior engineered solutions that replace low-tech asphalt-based felts and underlayments. These materials greatly improve the long-term integrity of the roof system while also providing the benefits of solar reflectance, energy efficiency and the benefits of being considered a "green" building product. The long-term benefits derived from these advancements far outweigh the energy and resources spent to create such synthetics.

Advancements in petroleum processing have resulted in reduction in the quality of asphalt felts (through a reduction in the quality of the asphalt byproducts). Tar-paper manufacturers have had to expend additional energy and resources to incorporate fiberglass fibers and other "binders" in an attempt to improve the durability of these roof underlayments. Synthetic underlayments are 100 percent polymerized, which provide tough and inert characteristics, unlike tar-paper felt, which are not chemically bonded and will degrade over time. Tar-paper felts are considered hazardous materials per California Proposition 65.


The Benefits

The foregoing benefits of radiant/synthetic underlayments provide roofing contractors, builders and architects with a way in which to provide long-term benefits with a payback of being considered "green." Contractors, builders and architects can upgrade their professional services to offer a roof system that provides a payback to the homeowner into the future. Contractors, builders and architects who embrace this approach will set themselves apart from the competition as the preferred professional to the property owner.


Mark Strait is president of Kirsch Building Products, Simi Valley, Calif.