Expert: James Ball - 11/17/2009

Question
Can multi purpose ready mixed joint compound be used to cover and smooth out the flat surface of fireplace brick?
I have a huge bucket of joint compound and wanted to use it if that would work. My fireplace is centered in a wall of brick, with a ledge 2 feet deep and 18" high from the floor.
I just want to smooth out and paint that ledge.
If that will not work, do I need to seal the brick before smoothing with some other compound before I paint?
Thank you

Answer
Hello Jeneanne, not sure what you are asking, you want to use joint compound in the firebox? or near the firebox? I do not think it will work as it is not  heat resistant and will crack.
the "ledge" sounds like a hearth extention and if so must be out of fire resistant stone, brick, slate, marble, granite... and that joint compound will not work there.
I have never been asked any thing like this and can't think of any thing to "cover the brick" on your hearth so you can paint it, other than just painting it.
James