How to Point a Wall: A Comprehensive Guide to Wall Repointing

How to Point a Wall: A Comprehensive Guide to Wall Repointing

Pointing a wall, commonly referred to as repointing, is a crucial maintenance task that involves renewing the external part of mortar joints in masonry construction. Over time, weathering and decay cause voids in the joints between masonry units (bricks, stone, etc.), allowing the undesirable entrance of water. Water entering through these voids can cause significant damage through frost weathering and from salt dissolution and deposition. Repointing is essential to prevent this and to prolong the life of the wall. This article will guide you through the process of pointing a wall.

Understanding the Importance of Repointing

The primary purpose of repointing is to ensure the longevity of a wall. When done correctly, it restores the visual and physical integrity of the masonry. This is not only important for structural reasons but also for aesthetic appeal, especially in older buildings where the preservation of original craftsmanship is crucial.

Materials and Tools Required

• Mortar mix (appropriate for the building’s age and type of brick or stone)
• Masonry trowel
• Pointing trowel
• Joint raker or old chisel
• Hammer
• Wire brush
• Bucket for mixing mortar
• Water
• Safety glasses and gloves

Step 1: Preparation

1. Select the Right Mortar: It’s essential to match the new mortar to the existing one in color, composition, and texture. For historic buildings, this might mean creating a custom mix.
2. Remove Old Mortar: Carefully rake out the old, damaged mortar to a depth of about 1/2 to 3/4 inch. Use a joint raker or an old chisel and hammer. Be careful not to damage the masonry units.
3. Clean the Joints: Once you’ve removed the old mortar, use a wire brush to clean out the joints. This ensures a clean surface for the new mortar to adhere to.

Step 2: Mixing the Mortar

1. Mix the Mortar: Follow the manufacturer’s instructions to mix the mortar. The consistency should be firm and workable but not too wet.
2. Let the Mortar Rest: Known as ‘slaking,’ let the mortar sit for a short period after mixing. This allows the water to fully penetrate the dry ingredients.

Step 3: Repointing the Joints

1. Fill the Joints: Use the pointing trowel to push mortar into the joints. Make sure the joints are filled completely with no air pockets.
2. Tool the Joints: Once filled, use the trowel or a jointing tool to finish the joint to match the original style. Different profiles can be created, such as flush, weather-struck, or recessed.
3. Clean Excess Mortar: Immediately clean any excess mortar from the face of the bricks or stones with a damp sponge.

Step 4: Curing

1. Keep the Mortar Damp: Lightly mist the repointed areas for a few days to slow down the curing process. This prevents the mortar from drying too quickly, which can lead to cracking.

Conclusion

Repointing a wall is a meticulous process that plays a crucial role in building maintenance, especially for older structures. It requires patience, precision, and an understanding of the building's masonry. Properly executed, repointing not only preserves the structural integrity of a wall but also its historical value and aesthetic appeal. Remember, if the wall is part of a historic building or if you’re unsure about the right mortar mix or technique, it’s advisable to consult a professional. With the right approach, repo