I am finishing my fireplace in the basement; it is block and has a gas fireplace. How do I refinish the block so that it is fireproof? How wide must the hearth be? Can I glue fire retardant gyproc to the blocks? Any great ideas would be appreciated.
Your best choice would be to use a cultured stone facing i.e.: California Cultured Stone or Eldorado Stone. You will find both very easy to apply and the final result will be fireproof and very original. Hearth width should be 16" deep and 10" to 12" off the floor. Keeping in mind this is normally already decided since you indicated you have a gas insert in place.