The process we recommend in the proper maintenance of exterior brickwork is to do as little intervention as possible in regard to the pointing mortar if in fact the large majority is still intact. A mason should replace only what is missing wholly, or eroded back more than 3/8″, with fresh mortar, which will match very closely to the original mortar in composition, color, texture and tooling. The total repointing of a building is often unwarranted. Patch pointing is cost conservative as well as functionally superior than pointing the whole building in an incorrect manner. If total repointing is to be done because the majority of the mortar is past its useful service life, a mortar should never be applied that consists of a Portland cement and fine sand paste placed over the top of the existing joint. This technique employed by many masons is superficial because of a shallow depth which lacks a good mechanical key to the surrounding brickwork. Over time this “scrub joint”, as it is sometimes referred to, may delaminate. However, the extreme disservice that this technique brings is that the fine Portland cement, which will pass through a #200 sieve, (a sieve where even a water droplet is not able to pass through), allows the wetting and drying cycles of the building, (a cause of masonry unit and joint weathering), to occur through the brick or stone thus exacerbating its breakdown instead of more of the mortar joint. The mortar joint is meant to be more sacrificial than the irreplaceable masonry units. The “wicking-in” of water through the brick or stone can then can be driven further into the building by blowing rainwater and cause interior damage.

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