Demand for synthetic roofing underlays will rise 7.6% per year to hit 111.7 million squares by 2020, at which point synthetics will be more popular than asphaltic roofing underlays, the Freedonia Group predicts.

Its new report, announced Dec. 12, said the sales gains will be driven by continuing interest from consumers, who have come to recognize the product's enhance resistance to moisture and its ease of installation.

Here's how the Cleveland-based research group sees the market develop:

Roofing Underlay Demand (millions of squares)
Item 2005 2010 2015 2020 2025
Total 244.1 167 181.1 214.5 234.5
Asphaltic 208.4 125 103.6 102.8 101.3
Synthetic 35.7 42 77.5 111.7 133.2

And here's how the relative market shares of asphaltic and synthetic underlay look based on Freedonia's forecast:

Freedonia Group's market share forecast

“Many contractors will specify these products because of their ability to reduce the time and cost of installation jobs, while others will opt for synthetic underlays because of their ability to be used as ice and water barriers," analyst Matt Zielenski said.

Freedonia also based its forecast on expected increases in construction spending, the adoption of building codes that specify synthetic underlays, and "builder interest in installing flame-resistant underlays, especially in commercial structures."

The full report is available at for $4,900.