Cement Board and 5/8 Inch Drywall Fire Rating
August 17th, 2010
Would you please tell me how long cement board/”c” board is fire rated for and how long 5/8 inch drywall is fire rated for?
Answer
Type “X” drywall is rated for one hour. This is 5/8 inch and it really depends on the entire package for that rating. For instance, using metal studs would/could give you more time than wood studs. Typically, Type “X” is rated for one hour. Doubling the layers will result in a two hour fire rating.
This “c” board is certified by each manufacturer with UL control. Generally, a rate of “A” is applied. Think of the three types of fire classifications ABC.