Not that long ago, plastic housewraps like Tyvek and Typar replaced organic felt paper as the standard siding underlayment. Now there's a new generation of synthetic roofing underlayments poised to displace felt paper up on the roof. To find out whether their advantages justify their higher prices, I recently gathered together as many of these roofing membranes as I could find.
Along with roofing contractor Martin Elle, who's a strong advocate of 30-pound felt-paper underlayment, I designed a simple field test to compare roofing underlayments from an installer's point of view and get an idea of how they perform.
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