How do I repair the inside of my fireplace?

Start by scrubbing excess ash and dust from the walls of the fireplace to expose the brick. Then clear any loose mortar from the firebox floor and walls. Repair the joints using heat-resistent mortar. After some drying time, clean up the joint lines for a smooth finish.Click to see full answer. Beside this, how do I fix the inside of my fireplace?Start by scrubbing excess ash and dust from the walls of the fireplace to expose the brick. Then clear any loose mortar from the firebox floor and walls. Repair the joints using heat-resistent mortar. After some drying time, clean up the joint lines for a smooth finish.Furthermore, how do you repair fireplace mortar? Place the mortar into the cracks or damaged area between the bricks. Push the loaded trowel across the area and push the mortar into the cracks and fill it completely. Repeat this as needed until the cracks are entirely filled with new mortar. Use a damp cloth and remove any excess mortar. Simply so, what can I use to fix a crack in my fireplace? Individual chimney bricks that have a small crack or two can be repaired with a high-heat mortar and a caulking gun. Clean out the crack with the edge of the putty knife or with the screwdriver. Sweep the crack clean with the wire brush. Squeeze the high-heat mortar into the crack as far as possible. How much does it cost to fix a fireplace?The average cost of a chimney repair is between $300 and $4000. The repair costs depend on the extent of the damage, the materials (type of brick, lining, flashing, etc), the current condition of the chimney crown, and the location of the chimney.