Re-pointing Chimney Mortar Joints

Re-pointing the mortar joints on a chimney is a necessary task to maintain the structural integrity and appearance of the chimney. The process involves removing the old, damaged mortar and replacing it with new mortar. Here are the steps to re-point the mortar joints on a chimney:

1. Assess the condition of the chimney: Before you begin, it's important to inspect the chimney to determine the extent of the damage. Look for cracks, missing mortar, and crumbling bricks.

2. Prepare the chimney: Start by removing any loose debris, such as leaves and twigs, from the chimney. Then, use a wire brush or a hammer and chisel to remove any loose or damaged mortar from the joints. Be careful not to damage the bricks or the underlying structure.

3. Mix the mortar: To make the new mortar, mix a small amount of Portland cement, hydrated lime, and water to a consistency that is easy to work with. The ideal consistency is that of peanut butter.

4. Apply the mortar: Using a pointing trowel or a small masonry trowel, fill the joints with the new mortar. Press the mortar firmly into the joint, making sure to fill it completely.

5. Tool the joints: Once the mortar is in place, use a jointing tool or a trowel to create a smooth, concave joint. This will help prevent water from penetrating the joint.

6. Clean up: After the mortar has dried, use a wire brush to remove any excess mortar that may have hardened on the bricks.

7. Repeat the process: Repeat the process until all the joints have been re-pointed.

It's important to note that re-pointing the mortar joints on a chimney is a job that should be done by a professional. Improperly re-pointing a chimney can lead to leaks and other issues. It's also important to consider the age and condition of the chimney before re-pointing it. If the chimney is in poor condition, it may be necessary to have it rebuilt or repaired.