Abstract: In general, the present invention is directed to a gypsum board comprising a gypsum core and a glass mat facing material including a coating. The coating comprises a resin including an acrylic resin, a siloxane rubber, or a mixture thereof and hydrophobic additive comprising an organosilane. The gypsum board passes at least one of the three air and water barrier tests specified in AC-212 wherein the tests comprise a water penetration barrier test as conducted in accordance with ASTM E331-00, a hydrostatic head test as conducted in accordance with AATCC 127-2008, or an air barrier test as conducted in accordance with ASTM E2357-11.

Abstract: In the present disclosure, a gypsum panel is disclosed. The gypsum panel comprises a gypsum core having a first gypsum layer surface and a second gypsum layer surface opposite the first gypsum layer surface and a fluted layer having a first fluted layer surface and a second fluted layer surface opposite the first fluted layer surface wherein the first fluted layer surface facing the first gypsum layer surface. The present disclosure is also directed to a method of forming the aforementioned gypsum panel.