Fireplace Question

Cement board will work and it available at tile stores. You may want to consider using some tile or slate flooring if you want to be more decorative. You can also find a place that specializes in woodstoves and fireplaces.

First, check your yellow pages under "Fireplaces". There may be a specialty store in your town that you haven't found yet. Home Despot or Lowe's may carry these things, but like the hardware store, you may get a blank stare when you ask.

Finally, a google search using the appropriate words should give you some answers. I won't give a hint about those words because if you can't think of them yourself, you probably shouldn't be operating a fireplace or handling anything trickier than a spoon.

Since you're concerned about meeting the code requirement, I'd check with the local building dept first. I'd be surprised if any temporary sheet material would meet the code. Why can't you remove the tile that is there and replace it with a slate hearth, etc which will be permanent and look good?

so it wasnt built to code? I would have a fireplace specialist come inspect everything including camera inspection of flue, and go from there.

there may be more than one code issue in that fireplace, better to know whats up, and a perodic flue inspection is always a good idea

Your situation involves three questions:

1. Practical safety from fire: guaranteed if you never use the fireplace.
2. Fire Safety Code. Where I live this is the only part of the Building Code that is retroactive (i.e. when the FSC changes you may be ordered to remodel your house so that it conforms. This does not happen for BC clauses about stairs, doorway widths, electrical code.)
3. Fire insurance. This can be the most difficult question when (as is common) insurance agents do not know much about either fire safety or the FSC. If in doubt, some may simply cancel your insurance.