The Point of Repointing
Renewing tired masonry joints can bring an old brick building back to life.
Synopsis: Repointing is the art of repairing old brick walls with new mortar and in some cases new brick. The author of this article, a mason and an author, explains how it’s done. A sidebar offers details on what type of mortar should be used.
Brickwork deteriorates. This is inevitable but not, fortunately, irreversible. Replacing bad bricks and repointing with new mortar can restore a building’s original integrity. And repointing, known as tuck pointing in the trade, is a job that can be handled by a careful homeowner. The resulting pride and satisfaction can be as substantial as the money saved.
In any repointing job, the first step is to determine exactly what the problem is. In some cases,the mortar simply has worn out. Old mortar often contains no portland cement, just lime and sand, with animal hair as a binder. These mortars can soften and break down over time, losing their ability to seal joints or adhere to brick. When this happens, they need to be replaced.
In other cases, improper flashing or structural damage to the roof has allowed water behind the brick. This water can be absorbed by the brick and mortar. As the wall drys out, the moisture escaping can cause the bricks to chip and the mortar to pop out. This problem is even more severe in colder climates where the expansion and contraction of freezing and thawing water accelerates the process. Sometimes the ground beneath the wall has settled. This can cause cracks in the wall, which might eventually require rebuilding. Before any actual repointing is done, find out why it needs doing, and correct these conditions first. If you don’t, all the effort and expense of repointing will be wasted.
Spring and fall are usually ideal times to…