Mortar used to lay bricks is a bonding compound of cement or lime, water, and sand. In an exterior wall, it is exposed to extremes of weather and needs to be repaired from time to time. There are a number of methods used to repair mortar joints. If the entire wall shows excessive wear and deterioration, the best repair alternative may be to simply tear down and rebuild the wall. However, in most cases this is impractical so the next best method of repair is tuck pointing. Tuck pointing is simply a means of replacing deteriorated mortar.
- Using a cold chisel, cut away any loose or deteriorated mortar from the joint needing repair. Angle the chisel so you cut toward the center of the joint, not toward the edge of the brick.
- Scrape away any loose mortar, dirt, and debris. You can use a stiff bristle wire brush to clean the joint thoroughly.
How To Tuck Point
- Prepare the mortar and place it on a mortar hawk or mortar board. It should be stiff like pudding but not any thinner and not crumbly like cookie dough.
- Hold the mortar board with mortar up at the bottom edge of the mortar joint.
- Using a pointed trowel, push mortar from the board into the mortar joint with the point of the trowel.
- Continue to pack the mortar into the joint until it is flush with the face of the brick.
- Lay down the mortar board and trim the mortar joint with a mortar strike tool.
- Be careful to avoid getting the mortar on the face of the brick.
You can use a grinder to clean out the joint needing repair. Be sure to use safety goggles, gloves, and dust respirators. Exercise great care that you do not damage the existing brickwork with the grinder.
Wet the mortar joint before repairing it with tuck pointing.
Strike the vertical joints, called cross joints, first. Then strike the horizontal, or bed, joints.
You can use a special striking tool or a piece of wood shaped to do the job.
On exterior walls, there are several different types of tuck pointing you can use depending on what you want to accomplish. You can finish the joints using the hollow key, struck, recessed, weathered, or flush method. Choose the method that best matches the existing finish.
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