Johns Manville

Passive Fire Protection Partners

Kenneth A Turpin

Monroe William Shumate

David J Duquette

Walter A Johnson

Steven N Volenec

Reed Harvey Larson

Edward A Bright

Richard A Versen

Bradley Burdic

Jesse J Beitel, Iii

Robert D Hamilton

A gypsum board/intumescent material ceiling board includes a gypsum board and a fire-resistive barrier. A first major surface of the gypsum board is an upper side for abutting framing and a second major surface of the gypsum board is an underside for facing a room interior. The fire-resistive barrier is a layer of intumescent coating material applied to and coextensive with one of the major surfaces of the gypsum board. The intumescent coating material contains expandable graphite and a corrosion inhibitor in sufficient quantities to provide a corrosion inhibiting layer on metal surfaces, such as the surfaces of metal fasteners, with which the intumescent coating material comes in contact. In addition, the intumescent coating material has a pH greater than 7.0 to reduce corrosive properties of the intumescent material and provide a chemical environment conducive to the forming of the corrosion inhibiting layer by the corrosion inhibitor.

Gypsum board/intumescent material ceiling boards

An intumescent material includes a liquid carrier with a corrosion inhibitor, such as a coating forming material, expandable particulate graphite (flake graphite or lump graphite) and if desired a filler. The intumescent material has a pH greater than 7.0, to reduce the corrosive properties of the intumescent material for most metals used in the construction industry and to provide a chemical environment conducive to the forming of a corrosion inhibiting layer by the corrosion inhibitor. The method of making the intumescent material includes combining the liquid carrier, the corrosion inhibitor, the expandable particulate graphite, the filler (if used), and a pH enhancer (if necessary to bring the intumescent material within the desired pH range), to form an intumescent material having a pH greater than 7.0.

Intumescent material

A gypsum board/intumescent material fire barrier wall includes spaced apart, vertically extending metal or wooden studs with only one layer of gypsum board secured to each side of the studs to form a fire barrier wall with a wall cavity. An intumescent material barrier, that is at least coextensive in width and height with the width and height of the wall cavity, is also included in the fire barrier wall and preferably, the wall cavity contains a fibrous insulation blanket. Preferably, the spaced apart gypsum wall boards, with the intumescent material barrier, provide the fire barrier wall with two hour fire-resistive properties meeting or exceeding ASTM test standard E119 for walls and partitions.

Gypsum board/intumescent material fire barrier wall

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Delta, Canada

Kenneth A Turpin