Understanding Gypsum Planks
Gypsum Planks
Gypsum planks are factory-laminated, typically 2 inches thick, 2 feet wide, and 8 feet long. Each plank weighs around 135 pounds. They are designed to span large spaces and are often used in conjunction with steel bar joists.
Understanding Gypsum Concrete Decking
Gypsum Concrete Decking
Gypsum concrete decking is formulated from calcined gypsum and wood chips or shavings. It is usually poured to a thickness of 2 inches and weighs approximately 17.5 pounds per square foot. This type of decking is also used to cover open web steel bar joists and is known for its lightweight construction.
Fire Safety Concerns
Fire Safety Concerns
Gypsum roof decking has a significant drawback in terms of fire safety. It is extremely vulnerable to moisture, which can cause the system to deteriorate. This, combined with truss construction, can lead to early collapse during fire operations. Firefighters are advised to exercise caution and evacuate the roof if they encounter gypsum decking during operations.
Retrofitting and Repair
Retrofitting and Repair
Although gypsum decking is no longer widely used, many existing structures still have it. Retrofitting and repairing these decks can be challenging, but materials like steel decks and mineral boards can be used to repair trouble areas. In some cases, it may be necessary to remove the gypsum deck and replace it with a new composite steel deck and roofing materials.