Check with a pro about dirty fireplace
A: If you are talking about painting the inside of a working fireplace - the firebox, which is where the logs go when you light a fire - I would not want to find out! Don't try this yourself with any paint or coating. They'll burn off as soon as you build a fire, releasing potentially harmful fumes into your house.
Do you use the fireplace regularly for heat? Call a qualified and licensed contractor, chimney sweep, mason specializing in chimneys and fireplaces, or a specialty fireplace shop. They'll help you decide on the best approach for cleaning and any necessary repairs.
Black soot that collects on the front of the fireplace, above the firebox, may result from poor air circulation. Again, a professional chimney sweep or mason will spot problems and recommend a cleaning process, based on your fireplace's materials and what you burn.
It may be less expensive to leave the fireplace operable, and just not use it. Remove the wood, matches and fireplace tools. A new or used metal-and-glass screen will improve your fireplace's appearance and may help reduce drafts. Fill the firebox with decorative electric candles or a flower arrangement for a romantic look. Or add an oversize, decorative screen or fan to hide the view completely.
Fireplaces add a lot to a home's value, so it's well worth protecting it.
Jennifer Adams is a designer, author, and TV personality.