Open joints around mortar beds signify a need to repair your brick wall. Even though repointing brick is a relatively simple process, it requires precision. One should first ensure that the brick on the wall is stronger than the mortar. Testing can be done in an engineering lab. Additionally, it is vital that you repoint brick only when temperatures stay within the range of 40 to 90 degrees Fahrenheit; even during the night. Fluctuating temperatures have different effects on the mortar. Cold temperatures can produce brittle mortar, while high temperatures dry the mortar, and prevent hardening.
Removing The Old Mortar
If the mortar has lost a quarter of an inch of the original depth, you will need to use a chisel. The best technique to repair such a wall is to thoroughly rake out and clean joints, without disturbing the mortar underneath. After raking out, you should ensure that you achieve a depth of twice the width of the joint.
It is also imperative to avoid to chipping the brick’s fire skin as this tends to accelerate the rate of brick decay. Moreover, it is important to avoid disturbing the old mortar around the windows, as this can affect opening and closing of the windows. Use the chisel to chip only loose material. Preferably, one should use a narrow chisel to prevent pushing loose material in the window frames.
Applying The New Mortar
After successfully removing the loose material, it is important to brush out the excess dust left between bricks. Repointing brick should be done from the top going downwards. Ensure that the mortar you use is of similar color to the color on the wall. Mortar of a different color will lead to a cosmetically unattractive wall.
To apply the mortar, first load the mortar on your trowel. Hold the trowel upside down. Then, scrape the mortar into the space using your trowel. Using a pointed trowel, squeeze the mortar in between the bricks. Allow the mortar to overlap the joints before neatening the wall. After the mortar is nearly dry, use a wire brush to remove excess mortar.
Preventing Damage by Moisture
Deteriorated bricks typically lose the ability to withstand weather elements such as frost, snow, or rainwater. When repairing a deteriorating brick wall, one main factor you should consider is to prevent as much water intrusion in the wall structure as possible. To achieve this, one can install a cap on the wall to keep moisture out. The cap can be a metal flashing, special bricks, or concrete designed in a way that it directs water away from the upper part of the wall.
Additionally, a sturdy wall should have proper weep holes and gravel along the bottom to relieve water pressure in case soil becomes saturated. Another technique to keep moisture away is to ensure that the backside of the wall is damp-proofed. An efficient drainage system should also be installed around the base of the wall to prevent water seeping in from below.
