How thick is a 1 hour fire rated wall?
The most common fire rated drywall is known as type X, which is 5/8 inches thick, placed on each side of 2 by 4 or 2 by 6 inch wood studs and has a minimum fire rating of 1 hour.
What is a 1 hour rated wall?
A “one-hour” fire rating is given to an assembly consisting of various building materials that can resist the exposure of a standardized fire exposure for one hour.
What is fire rated gypsum board?
Fire-rated gypsum board is a form of drywall that helps prevent the spread of flames across a home or business. Gypsum is approximately 21% chemically combined water, which greatly contributes to its effectiveness as a fire-resistive barrier.
Can you double layer drywall?
Install the second layer of drywall on both the ceilings and the walls, with the sheets fitted at a 90-degree angle to the first layer. As with the first layer, cover the ceiling first before the walls. The ceiling screws and wall nails need to be longer to accommodate the extra thickness of the second drywall layer.
Is gypsum fire resistant?
Fire rated gypsum drywall is more fire resistant because it contains glass fiber reinforcement and other additives within its specially formulated gypsum core to help it hold up longer to a fire exposure.
Does a 1 hour fire rated wall require a fire damper?
Q: Are fire dampers required in one-hour fire-rated walls if the facility is fully sprinkled? A: According to NFPA 90A (1999 edition), one-hour fire-rated barriers do not require fire dampers in fully ducted HVAC systems, unless the one-hour fire-rated barrier is a vertical shaft.
Is gypsum flammable?
Gypsum is a soft mineral that by itself is not flammable. Additionally, water is incorporated into its structure. In the presence of fire, heat energy vaporizes the water, removing it gradually. Water effectively blocks the transfer of heat through the drywall.
What is the size of gypsum board?
The standard size gypsum boards are 48 in. wide and 8, 10, 12, or 14 ft. long.