The most durable paper board on the market with a True Density™ rating of 3.3. Builder Board replaces the need for large, bulky sheets of masonite and rolls out fast and flat. With Liquid Shield technology, Builder Board is also spill proof. It defends against water, paint, mud and more! It's also 100% recyclable. Builder Board is sold as a 38" x 100' roll. Just one roll will cover the same area as 10 sheets of masonite.