Tuck Pointing or Repointing
Tuck Pointing or Repointing is the process of raking out one to
two centimeters of mortar from the joints of brick or stone and
replacing it with new mortar. It is required where mortar has
deteriorated by weathering (often due to uncontrolled rainwater)
or when structural movement has opened up the joints. Repointing
should be applied only where necessary. Removal of sound mortar
for the sake of doing an entire wall, for example, is structurally
unnecessary and can lead to damage of the masonry units. Instead,
effort should be put into closely matching the pointing mortar
to the color and texture of the existing mortar.
Good pointing allows rain water to flow over it and away, it also
allows the free evaporation of moisture from within the wall.
Degraded or projecting pointing will trap water and can channel
it into the wall. If the mortar used is harder than the stone
or brick adjacent to it, evaporation will occur via the faces
of the stone. Salts can accumulate and, combined with frost damage,
this can cause serious erosion of softer stones.