Converting a fireplace from one use to another always requires an inspection of the chimney as well as the actual fireplace. Gas fires produce far less heated smoke through the chimney and therefore don't have the tougher requirements of a wood burning fire. In most cases where builders designed the original chimney of brick or rock suitable in size for a wood fire, the conversion is simple. However, if the fireplace was designed for a gas fire, you may not be able to convert to burning wood without some complicated upgrades.
Inspect the chimney both from the inside of the house and from the roof. Look for a strong structure of stone, block or brick in good repair. Any missing sections of mortar signify that the chimney needs repair from a professional and certified repairman.
Identify what kind of liner is in the chimney leading from the fireplace to the roof. If there is a 5/8-inch thick liner made of fireclay, the chimney is designed for wood burning and as long as the flue is in good condition, burning wood fires is safe. If the chimney is old or the flue isn't in good condition, have a professional install a metal liner to go from the fireplace to the roof.
Turn off the gas lines leading to the fireplace. Natural gas lines in your home have a shutoff lever where the gas feeds into your home and for the fireplace. Bottled propane also has shutoff valves both in the home and outside at the bottle.
Remove the gas apparatus from your fireplace. You may need to cut the copper gas feed line if the previous installation ran the line through the structure of the fireplace. Crimp and flatten the line flush with the surface of the masonry of the fireplace.
Install a wood-burning grate and doors over the front of your fireplace to increase the heat efficiency of the fire.