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Is Type X Gypsum Required on a Basement Ceiling?

Type X gypsum boards have a fire resistant core. Fire ratings for these boards reach four hours. In addition to the fire resistant qualities, Type X boards also provide a thermal and sound barrier.
  1. Ceiling Application

    • A fire resistant ceiling consists of two layers of 5/8 inch type X gypsum board applied directly to the framing. Used on a basement ceiling it will take one hour for flames to burn through two layers, providing time to put the fire out and to save the structure of the home or building.

    Building Codes

    • Some area building codes require a minimum of ½ inch type X gypsum board on the connecting wall between an attached garage and a dwelling. If the garage is underneath habitable rooms, the garage ceiling must consist of at least one layer of 5/8 inch type x gypsum board. For requirements of basement ceilings and other parts of a dwelling, consult your local codes.

    Fire Ratings

    • Type x gypsum wall and ceiling boards do not have a fire rating, individually. Fire ratings are assigned to a completely constructed dwelling. The rating is based on the thickness of the boards, the number of layers and where the boards are installed in relation to the rest of the dwelling.