what is type c & x drywall
Norm Abram replies: The 5/8-inch, fire-code drywall (called Type X) increases a wall's fire rating to a minimum of 1 hour, from the 30-minute rating for standard Â½-inch drywall. And it's not just thickness that makes the difference. Type X has a denser core and contains glass fibers that keep it from crumbling in the heat.