http://www.dickseibert.com/martin.pdf
Like asphalt felt, Grade D building
paper is an asphalt-saturated paper. It
differs from asphalt felt in two ways: It
uses a lighter-weight paper, and the
paper is made from new paper pulp
rather than recycled cardboard. “Grade
D paper is a kraft paper, made with virgin
fiber,” says Bob Woykin, sales manager
at Hal Industries, a manufacturer
of Grade D paper in Surrey, B.C.
“Roofing felt is thicker than Grade D
paper and is 100 percent recycled. The
asphalt used to saturate the Grade D
papers and the roofing felts is about the
same,” he says.
Gary