How to Repair Fireplace Mortar

Cracked or damaged fireplace bricks and mortar hold the potential for unwanted fires in the home. Large cracks in the mortar allow cinders to work their way into the floorboards underneath the fireplace, creating a potential safety hazard. An economical way to ensure the safety of a fireplace is to repair fireplace mortar that has become old, incomplete or cracked.

Difficulty: Moderate

Instructions

Things You'll Need:

• Brush
• Goggles
• Mask
• Mortar
• Water
• Trowel
• Cloth
• Paintbrush

1. Brush crumbling and broken mortar from between bricks with a wire brush. This clears the area of debris and prepares the surface of the fireplace for new mortar. Use a mask to avoid inhalation of mortar dust and goggles prevent dust from entering the eyes.

2. Prepare mortar with water following the direction on the back of the packet. Although reasonably inexpensive fireplace mortar is a specialist product often only available at masonry supply stores. Be sure the mortar you choose is specifically for use with fireplaces or high heat zones.

3. Place a small amount of mixed mortar onto a masonry trowel. Be sure to choose a trowel size that works for you. Often, standard size trowels can be difficult for people with small hands.

4. Smear the mortar into the cracks between fireplace bricks by pushing the loaded trowel across the area. It doesn't have to be perfect; the idea is simply to get as much mortar as possible into the crack to fill it completely. More than one pass over with a loaded trowel could be necessary.

5. Remove excess mortar from the surface of the fireplace using a damp cloth. This will tidy up the area, smooth the surface of the repair and push mortar even deeper into the cracks.

6. Allow the mortar to dry completely in accordance with the directions on the packet.

7. Use a paintbrush to brush away any excess debris from the surface of the new mortar.

[Sweeper]

on 7/21/2008 Floorboards UNDER the fireplace??? Do you have any conceptual knowledge of just HOW a masonry fireplace is actually built. Under the firebrick floor of such a unit is at least a 10-12 inch, if not deeper concrete base added to the concrete footing which is required to support the tremendous wieght of the stone/block and/or brick from which the entire structure is built. I'd like to know where this writer has EVER seen a masonry fireplace built on a WOOD floor, which to begin with wouldn't even support the mass of weight, but then I could be wrong, eh. I cannot beleive the amount of mis-information, some of it foolish, some of it down-right dangerous on this site when it comes to wood burning systems.